Synthesis and Application of Novel Ruthenium Catalysts for High Temperature Alkene Metathesis

21 Pages·2017·9.16 MB·English

catalysts

ArAtirctliecle 
Synthesis and Application of Novel Ruthenium
Synthesis and Application of Novel Ruthenium 
Catalysts for High Temperature Alkene Metathesis
Catalysts for High Temperature Alkene Metathesis 
TegeneT.Tole,JeanI.duToit,CorneliaG.C.E.vanSittert,JohanH.L.Jordaanand
Tegene T. Tole, Jean I. du Toit, Cornelia G. C. E. van Sittert, Johan H. L. Jordaan and Hermanus 
HermanusC.M.Vosloo*
C. M. Vosloo * 
ResearchFocusAreaforChemicalResourceBeneficiation,CatalysisandSynthesisResearchGroup,
Research Focus Area for Chemical Resource Beneficiation, Catalysis and Synthesis Research Group, North‐
North-WestUniversity,HoffmannStreet,2531Potchefstroom,SouthAfrica;[email protected](T.T.T.);
West University, Hoffmann Street, 2531 Potchefstroom, South Africa; [email protected] (T.T.T.); 
[email protected](J.I.d.T.);[email protected](C.G.C.E.v.S.);[email protected](J.H.L.J.)
[email protected] (J.I.d.T.); [email protected] (C.G.C.E.v.S.); [email protected] (J.H.L.J.) 
* Correspondence:[email protected];Tel.:[phone]
*  Correspondence: [email protected] (H.C.M.V.); Tel.: +27‐18‐299‐1669 
AcademicEditors:AlbertDemonceau,IleanaDragutanandValerianDragutan
Academic Editors: Albert Demonceau, Ileana Dragutan and Valerian Dragutan 
Received:24November2016;Accepted:3January2017;Published:10January2017
Received: 24 November 2016; Accepted: 3 January 2017; Published: date 
Abstract: Fourpyridinylalcoholsandthecorrespondinghemilabilepyridinylalcoholatoruthenium
Abstract: Four pyridinyl alcohols and the corresponding hemilabile pyridinyl alcoholato ruthenium 
carbene complexes of the Grubbs second generation-type RuCl(H IMes)(OˆN)(=CHPh), where
2
OˆcNarb=en1e- (c2o(cid:48)m-ppylreixdeisn yolf) -1th,1e- dGipruhbebnsy lsemcoentdh agneonleartaot,io1n-‐(t2y(cid:48)p-pey RriudCinl(yHl)2-I1M-(e2s(cid:48))-(cOh^loNr)o(p=ChHenPyhl)),, 1w-phheerne y l
mOet^hNan o=l a1to‐(,2′‐1p-y(2ri(cid:48)d-pinyyrli)d‐1in,1y‐dl)i-p1h-(e4n(cid:48)-yclh lmoreotphahneonlyalt)o,1, -p1‐h(e2n′‐pyylrimdientyhla)‐n1o‐(l2a′t‐ochloarnodph1en-(y2l(cid:48))-,p1‐yprhideninyyl l)-
methanolato,  1‐(2′‐pyridinyl)‐1‐(4ʹ‐chlorophenyl),1‐phenyl  methanolato  and  
1-(2(cid:48)-methoxyphenyl),1-phenyl methanolato, are synthesized in very good yields. At high
1‐(2′‐pyridinyl)‐1‐(2′‐methoxyphenyl),1‐phenyl methanolato, are synthesized in very good yields. 
temperatures,theprecatalystsshowedhighstability,selectivityandactivityin1-octenemetathesis
At high temperatures, the precatalysts showed high stability, selectivity and activity in 1‐octene 
compared to the Grubbs first and second generation precatalysts. The 2-/4-chloro- and
metathesis compared to the Grubbs first and second generation precatalysts. The 2‐/4‐chloro‐ and 
4-methoxy-substituted pyridinyl alcoholato ligand-containing ruthenium precatalysts showed
4‐methoxy‐substituted pyridinyl alcoholato ligand‐containing ruthenium precatalysts showed high 
high performance in the 1-octene metathesis reaction in the range 80–110 ◦C. The hemilabile
performance  in  the  1‐octene  metathesis  reaction  in  the  range  80–110  °C.  The  hemilabile  
4-methoxy-substituted pyridinyl alcoholato ligand improved the catalyst stability, activity and
4‐methoxy‐substituted pyridinyl alcoholato ligand improved the catalyst stability, activity and 
selectivityfor1-octenemetathesissignificantlyat110◦C.
selectivity for 1‐octene metathesis significantly at 110 °C. 
KeKyewyworodrsd:sa: lkaelnkeenmee tamtheetastihs;ehsiesm; ilhaebmileilalibgialen dl;ipgyanridd;i nyplyarildcoinhyoll ;raulcthoehnoilu; mrucathrebneniuem;G  rcuabrbbse-ntye;p  e
prGecrautbablys‐stty;p1e-o pcrteecnaetalyst; 1‐octene 

1.1I.n Itnrotrdoudcutcitoinon 
ThTehew welel-lld‐defiefnineeddG Grruubbbbss fifirrsstt ((11 aanndd 22)) [[11––44]] aanndd sseeccoonndd ((33)) [[55––77] ]ggeenneeraratitoino nprperceactaatlaylsytss tasrae re
fofuonudndto tob ebev evreyrya catcitviveea annddr roobbuussttt toowwaarrdd aa llaarrggee nnuummbbeerr ooff ssuubbssttrraatteess. .TThhesees epprerceactaatlaylsytsst hsohwoewveevr er
shsohwowededa catcivtiivtiytya tatr orooommt etemmppeerraattuurree iinn aallkkeennee mmeettaatthheessiiss rreeaaccttiioonnss [[22,8,8,9,9].] .AAltlhthououghg hthtehye ypepreforfromr m
execxeclleelnletnat tarto roomomte tmempperearatuturere,,t htheeyyh haavveea a rreellaattiivveellyy sshhoorrtt ccaattaallyyttiicc lliiffeettiimmee. .
N N N N
Ph P Cy P
3 Cl 3 Cl Cl Cl
Ru Ph Ru CHPh Ru CHPh Ru CHPh
Cl Cl Cl O
PPh Ph PCy PCy
3 3 3 (cid:2) N
C
1 2 3
Ph
4  
ThTehefi rfsirts3t1 3P1PN NMMRRi ninvveessttiiggaattiioonn ooff aa hheemmiillaabbiillee pprrooppeerrttyy oof fSS‐O-O lilgigaanndds sinin PPdd cocmomplpelxeexse osfo tfhteh e
typtyepter atnrasn-[sP‐[dP(dO(OOOCC-C‐C6H6H4-42‐2SSRR-‐kk11-‐OO))]]PPhh((PPPPhh33))22 ((RR == iPiPr,r ,tBtBuu),) w,whehreerieni nonoen ePPPhP3h l3igliagnadn dis irseprelpaclaedce bdyb y
asau lfsuurlfautor maotofmth eSo-fO  ltihgea ndS‐tOo aflfiogradndch eltaot esa,fifnorsdo luctihoenla,twesa,s  rienp orstoeldutbioynR, auwbaesn heriempoerrteetda l.b[y1 0 ].
Grubbs-typeprecatalystswithhemilabileligandsshowedgreaterlifetimesandstability[10,11]. Itwas
Catalysts 2017, 7, 22; doi:10.3390/catal7010022  www.mdpi.com/journal/catalysts 
Catalysts2017,7,22;doi:10.3390/catal7010022 www.mdpi.com/journal/catalysts
Catalysts 2017, 7, 22  2 of 21 
Catalysts2017,7,22 2of21
Raubenheimer et al. [10]. Grubbs‐type precatalysts with hemilabile ligands showed greater lifetimes 
aalnsdo sretapboirlitteyd [[1102,1]1th].a Itt twhease laelcstor ornepicoartnedd s[t1e2r]i ctheaffte tchtse, etolegcetrthoenricw ainthd tshteerriicn egffseicztes,a tnodgertighiedri wtyitohf tthhee 
hrienmg islaizbeil eanbdid reingtiadtietyli goaf ntdhse, hcaenmpiloasbsiilbel ybiidneflnuteantec elitghaensdtsa,b cilaitny poofstshieblcyo minpflluexentocew thheic hstathbeilbitiyd eonf ttahtee 
lciogmanpdleixs atott awchheicdha nthde cboindseenqtuaeten tlliygathned ciast aaltyttaicchpeedr faonrmd acnocnes.eDquifefenrtelyn ttghreo ucaptsalfyotlilco wpeerdfodrimffearnecnet. 
dDeifsfiegrnencto gnrcoeupptss foofllionwitieadto drisffienretnhte dveasirgionu csonpcreepcatsta olyf sintsititaotoorbst ianin thteh evramrioalulys -psrweictacthaalybslets itnoi toibattoairns 
(tShcehrmemalely1‐)s[w13it]c.hable initiators (Scheme 1) [13]. 
L1 L1 L1 L1
Cl Cl Cl Cl
Ru CHR Ru Ru CHR Ru C(H)XR
ClL2 ClL X L ClL2
A B C D
L1=PR , H IMes; L2=PR
3 2 3  
SchSecmheem 1e. 1D.eDseigsing ncoconncceeppttss ffoorr tthheerrmmaalllyly-s‐wswitcithcahbalebline iitniaittoiarst.ors. 
In the design concepts shown in Scheme 1, the intention in all is to slow down or prevent the 
InthedesignconceptsshowninScheme1,theintentioninallistoslowdownorpreventthe
ddiissssoocciiaattiioonn ooff LL22.. MMoottiiff AA iiss tthhee ccllaassssiiccaall GGrruubbbbss pprreeccaattaallyyssttss wwhheerree LL22 iiss mmoossttllyy eeiitthheerr PPCCyy3 [[44]] oorr 
3
HH2IIMMeess [[77]],, wwhhiillee iinn MMoottiiff DD,, aa hheetteerroo‐-aattoomm lliikkee ssuullffuurr [[1144]] iiss ttyyppiiccaallllyy iinnttrroodduucceedd iinn tthhee aallkkyylliiddeennee 
2
ligand of these precatalysts. Hoveyda et al. [15–18] synthesized precatalysts with Motif B that showed 
ligandoftheseprecatalysts. Hoveydaetal.[15–18]synthesizedprecatalystswithMotifBthatshowed
exceptional stability that allowed its use in reagent‐grade solvents and/or in air [15], while this motif 
exceptionalstabilitythatalloweditsuseinreagent-gradesolventsand/orinair[15],whilethismotif
was also used by Van der Schaaf et al. [14] for the fine‐tuning of gel times for the better handling of 
was also used by Van der Schaaf et al. [14] for the fine-tuning of gel times for the better handling
ROMP (ring‐opening metathesis polymerization) in technical processes. In Motif C, where X is 
ofROMP(ring-openingmetathesispolymerization)intechnicalprocesses. InMotifC,whereXis
oxygen, the chelating ligand competes in both initiation and coordination with the incoming alkene 
oxygen,thechelatingligandcompetesinbothinitiationandcoordinationwiththeincomingalkene
substrate for a vacant coordination site [17]. The synthesis of this design concept was first achieved 
substrateforavacantcoordinationsite[17]. Thesynthesisofthisdesignconceptwasfirstachieved
by Grubbs et al. [19] and later by Verpoort et al. [20,21]. Herrmann and co‐workers synthesized the 
byGrubbsetal.[19]andlaterbyVerpoortetal.[20,21]. Herrmannandco-workerssynthesizedthe
hemilabile pyridinyl alcoholato ligand‐containing complexes and found low catalytic activity for 
hemilabile pyridinyl alcoholato ligand-containing complexes and found low catalytic activity for
ROMP; however, the activity increased with an increase in temperature as was observed for 3 [11]. A 
ROMP;however,theactivityincreasedwithanincreaseintemperatureaswasobservedfor3[11].
closely‐related precatalyst was also synthesized by Hafner et al. [22]. Because of the increase in the 
Aclosely-relatedprecatalystwasalsosynthesizedbyHafneretal.[22]. Becauseoftheincreaseinthe
catalytic lifetime as a result of hemilability, we were interested in the design concept shown in Motif 
catalyticlifetimeasaresultofhemilability,wewereinterestedinthedesignconceptshowninMotifC.
C. In line with this, Jordaan [23] synthesized 4 and other ruthenium‐based precatalysts by modifying 
Inlinewiththis,Jordaan[23]synthesized4andotherruthenium-basedprecatalystsbymodifying
the bidentate hemilabile ligand of Herrmann et al. [11] and Hafner et al. [22]. The precatalyst 4 has 
thebidentatehemilabileligandofHerrmannetal.[11]andHafneretal.[22]. Theprecatalyst4has
sshhoowwnn aann eennhhaanncceedd ccaattaallyysstt lliiffeettiimmee ccoommppaarreedd ttoo GGrruubbbbss pprreeccaattaallyyssttss aatt 6600 ◦°CC [[2244]].. FFuurrtthheerrmmoorree,, iittss 
ooppttiimmuumm tteemmppeerraattuurree iiss 8800 ◦°CC iinn 11-‐oocctteennee mmeettaatthheessiiss.. 
Our aim is synthesizing a precatalyst that is active, highly selective and having a longer catalytic 
Ouraimissynthesizingaprecatalystthatisactive,highlyselectiveandhavingalongercatalytic
lifetime at higher temperatures. This is because in industry, mainly linear alkenes are produced 
lifetime at higher temperatures. This is because in industry, mainly linear alkenes are produced
typically at high temperatures (e.g., alkenes are produced in high temperature Fischer–Tropsch 
typically at high temperatures (e.g., alkenes are produced in high temperature Fischer–Tropsch
pprroocceesssseess ooppeerraattiinngg aatt ttyyppiiccaallllyy >>330000 °◦CC [[2255]])),, tthhuuss rreedduucciinngg tthhee nneeeedd ttoo lloowweerr pprroocceessss tteemmppeerraattuurreess 
too low to add further value to the alkene pool. In this paper, we investigated the influence of an 
toolowtoaddfurthervaluetothealkenepool. Inthispaper, weinvestigatedtheinfluenceofan
electron‐withdrawing (Cl) and an electron‐donating (OMe) substituent, ortho or para on one of the  
electron-withdrawing(Cl)andanelectron-donating(OMe)substituent,orthoorparaononeofthe
α‐phenyl rings of 4, on its catalytic performance in 1‐octene metathesis. With this aim, the synthesis 
α-phenylringsof4,onitscatalyticperformancein1-octenemetathesis. Withthisaim,thesynthesis
and characterization of p‐chloro‐, p‐methoxy‐ and o‐chloro‐substituted pyridinyl alcohols and the 
and characterization of p-chloro-, p-methoxy- and o-chloro-substituted pyridinyl alcohols and the
corresponding derivatives of 4 were successfully performed. Investigations of their catalytic activity, 
correspondingderivativesof4weresuccessfullyperformed. Investigationsoftheircatalyticactivity,
sseelleeccttiivviittyy aanndd ssttaabbiilliittyy iinn 11-‐oocctteennee mmeettaatthheessiiss wweerree mmaaddee iinn tthhee tteemmppeerraattuurree rraannggee ooff 7700––111100 ◦°CC.. 
2. Results and Discussion 
2. ResultsandDiscussion
22..11.. SSyynntthheessiiss ooff PPyyrriiddiinnyyll AAllccoohhoollss 
AAlltthhoouugghh tthheerree aarree mmoorree ththanan 212 1didffieffreernetn mt emthetohdosd [s26[]2 6o]f osyfnstyhnetshizeisnizgi npgyrpidyirniydli naylcloahlocolsh, owlse, 
wfoellofowlleodw tehde thsterasitgrhaitgfohrtwfoarrwda radnda nrdelraetilvateilvye lsyimsipmlep lseysnythnethtiect ircoruotue teofo fHHererrmrmanann neet taall. .[[2277]] ttoo 
ssyynntthheessiizzee tthhee ppyyrriiddiinnyyll-‐aallccoohhoollss 55––88 ((SScchheemmee 22)).. AAss wwaass mmeennttiioonneedd eeaarrlliieerr,, oouurr aaiimm iiss ssyynntthheessiizziinngg 
1‐(2′‐pyridinyl)‐1,1‐diphenyl‐methanols having chlorine and/or methoxy substituents on one of the 
phenyl rings.
Catalysts2017,7,22 3of21
1-(2(cid:48)-pyridinyl)-1,1-diphenyl-methanolshavingchlorineand/ormethoxysubstituentsononeofthe
pCChaatteaallnyyssyttsls  22r00in1177g,,  s77.,,  2222   33  ooff  2211  
11..nnBBuuLLii,,EEtt OO,,--7788°°CC,, 3300mmiinn OOHH
22
BBrr NN 22..kkeettoonnee,,EEtt22OO,,--2200°°CC,,2200--2255°°CC,,22hh NN RR == HH ((55))
33..HH33OO++ RR PPhh RR == 22--CCll ((66))
RR == 44--CCll ((77))
OO
RR == 44--OOMMee ((88))
kkeettoonnee== RR PPhh

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S((11p44e..5r5b%%e))r,,  ooeuutrra  yly.i’ieselldd[2  ff8oo]rr y 55i  eiissld  ffaa(rr1  bb4e.e5tt%tteerr),..  TTohhueeryyy  rrieeeaaldcctteefddor  pp5iiccooislliinnfaiiccr  aabcceiitddt  eaarnn.ddT  bbheeennyzzoorppeahhceetnneoodnnepe  i((c11o::66li))n  iiinnc  ppa‐‐ccciyydmmaeennndee  
bssooellnvvzeeonnptt  hffooenrr  oaanbbeoouu(1tt  :666  )hhi..n  MMp-cccCCyaamrrtteyyn  eeett s aaolll..v  [[e22n99]]t  ifinnocrcrraeebaaosseeuddt  6tthhhee.  yyMiieecllCdd a oorfft  y55  ettoot  a22l55.%%[2  9bb]yyi  naacddrddeiainnsgged  tthhteeh  eppyiicciooellliidnniioccf  aa5cctiiddo  
2oo5vv%eerrb  aay  11a––d33d  hhin  pgpeetrhriieooddp  icttooo  laain  rriceeffalluucixxdiinnoggv  eppr‐‐ccayy1mm–3eennheep  sseoorillouudttiiootonn  aoorffe  bbfleeunnxzzinoopgphhpee-cnnyoomnneee..n  UUesssoiinnluggt  ittohhnee  ossfaambmeeen  zpporrpoohcceeeddnuuonrreee,,.  
UMMscciCCngaarrttthyye  eestta  maall..e  [[p22r99o]]c  sseyydnnuttrhheee,ssMiizzceeCdda  22rt55y%%e  tooaff  l.77[,,  2ww9]hhsiiycchhn  tiihsse  ttshhizrreeedee  2ttii5mm%eesso  fllee7ss,ssw  tthhhiaacnnh  ooisuutrrh  yryeiieeelltddim..  TTehhseeleyys,,  shhtoohwwaneevvoeeurrr,,  
yooibbettlaadii.nnTeeddh e y77,  h((66o88w%%e))v  eaar,nnoddb  t66a  in((44e22d%%7))(  6bb8yy%  )ffiiarrnssttd   pp6rr(ee4pp2aa%rri)innbggy  fitthhreest  pnnrBBeuupLLaiir  inffooglllltoohwweeenddB  ubbLyyi  frroeellaaoccwttiinnedgg  biiytt  rwweaiittchhti  n22g‐‐
ibbtrrwoommithoopp2yy-brriirddoiimnneeo  paayttr  id−−i66n00e––−−a44t00−  6°°0CC–.. −  TT4hh0ee◦  Cll.iittThhhiiuuemmli  thssiaaullmtt   oosfaf  lt22o‐‐bbfrr2oo-mmbroooppmyyorrpiiddyiirnnieed  inwweaawss  attshhteehnne  nrrreeeaaaccctteeteddd   wwwiiittthhh    
444-‐‐ccchhhlllooorrrooobbbeeennnzzzoooppphhheeennnooonnneee  aaannnddd  222‐-‐ccchhhlllooorrrooobbbeeennnzzzoooppphhheeennnooonnneee  aaattt  −−−666000  °°◦CCC  aaannnddd  ttthhheeennn  aaallllllooowwweeeddd  tttooo  rrreeeaaacccttt  fffooorrr  222  hhh  aaattt    
−−−444000  °°◦CCC..  .PPPyyyrrriiddidiinninyyyll  laaallcclcooohhhoooll  l888  wwwaaasss  sssyyynnnttthhheeesssiiizzzeeeddd  fffooorrr  ttthhheee  fffiiirrrsssttt  tttiiimmmeee...  
222...222...  SSSyyynnnttthhheeesssiiisss  ooofff  ttthhheee  LLLiiittthhhiiiuuummm  SSSaaallltttsss  aaannnddd  ttthhheee  CCCooorrrrrreeessspppooonnndddiiinnnggg  CCCooommmpppllleeexxxeeesss  
TTThhheee  llliiittthhhiiiuuummm  sssaaallltttsss  ooofff  ttthhheee  aaalllcccooohhhooolllsss  555–––888  wwweeerrreee  ppprrreeepppaaarrreeeddd  iiinnn  aaa  SSSccchhhllleeennnkkk  tttuuubbbeee  bbbyyy  ssstttiiirrrrrriiinnnggg  ttthhheee  pppyyyrrriiidddiiinnnyyylll  
aaalllcccooohhhooolllsss  wwwiiittthhh  nnnBBBuuuLLLiii  sssooollluuutttiiiooonnn  iiinnn  TTTHHHFFF  aaattt  rrroooooommm  ttteeemmmpppeeerrraaatttuuurrreee  iiinnn  aaannn  aaarrrgggooonnn  aaatttmmmooosssppphhheeerrreee  (((SSSccchhheeemmmeee  333)))  [[[222222]]]...  
TTThhheee  yyyiiieeelllddd  pppeeerrrccceeennntttaaagggeee  ooofff  ttthhheee  llliiittthhhiiiuuummm  sssaaallltttsss  ooofff  ttthhheee  pppyyyrrriiidddiiinnnyyylll-‐‐aaalllcccooohhhooolllsss  wwwaaasss  nnnooottt  cccaaalllcccuuulllaaattteeeddd,,,  aaasss  ttthhheee  llliiittthhhiiiuuummm  
sssaaallltttsss  aaarrreee  vvveeerrryyy  ssseeennnsssiiitttiiivvveee  tttooo  mmmoooiiissstttuuurrreee  aaannnddd  oooxxxyyygggeeennn  (((aaaiiirrr)))...  TTThhheee  llliiittthhhiiiuuummm  sssaaallltttsss  wwweeerrreee  kkkeeepppttt  iiinnn  ttthhheee  SSSccchhhllleeennnkkk  tttuuubbbeee  
uuunnndddeeerrr  ttthhheee  aaarrrgggooonnn  aaatttmmmooosssppphhheeerrreee  fffooorrr  ttthhheee  sssyyynnnttthhheeesssiiisss  ooofff  ttthhheee  cccooommmpppllleeexxxeeesss  ssshhhooowwwnnn  iiinnn  SSSccchhheeemmmeee  444...  
OOHH OOLLii
RR == HH ((55)) RR == HH ((99))
RR == 22--CCll ((66)) NN NN RR == 22--CCll ((1100))
nnBBuuLLii,,TTHHFF,,2200--2255°°CC,,22hh
RR == 44--CCll ((77)) RR PPhh RR PPhh RR == 44--CCll ((1111))
RR == 44--OOMMee ((88)) RR == 44--OOMMee ((1122))

SScchhSeecmmheee m 33..e  SS3yy.nnSttyhhneetthtiiecct  irrceerpperrpeersseeesnnenttaatattiitooionnn  ooofff  ttthhheee  sssyyynnnttthhheeesssisiisso  ooffft  htthheeeli  tllhiittihhuiimuummsa  lsstaasllottssf  pooyff  rppidyyirrniiyddliinnalyycllo  aahlloccloos.hhoollss..  
TThhee  lliitthhiiuumm  ssaallttss  ooff  tthhee  ppyyrriiddiinnyyll  mmeetthhaannoollss  99––1122  wweerree  aaddddeedd  iinnttoo  aa  SScchhlleennkk  ttuubbee  ccoonnttaaiinniinngg  aa  
Thelithiumsaltsofthepyridinylmethanols9–12wereaddedintoaSchlenktubecontaininga
TTHHFF  ssoolluuttiioonn  ooff  tthhee  GGrruubbbbss  22  pprreeccaattaallyysstt  iinn  aann  aarrggoonn  aattmmoosspphheerree  aanndd  ssttiirrrreedd  ttoo  rreessuulltt  iinn  tthhee  GGrruubbbbss  
THFsolutionoftheGrubbs2precatalystinanargonatmosphereandstirredtoresultintheGrubbs
22‐‐ttyyppee  pprreeccaattaallyyssttss  44  aanndd  1133––1155,,  aass  sshhoowwnn  iinn  SScchheemmee  44..  
2-typeprecatalysts4and13–15,asshowninScheme4.
TThhee  nniittrrooggeenn  cchheellaattiioonn  ooff  tthhee  ppyyrriiddiinnyyll‐‐aallccoohhoollaattoo  lliiggaannddss  ttoo  tthhee  rruutthheenniiuumm  mmeettaall  ccaann  bbee  sseeeenn  
ffrroomm  tthhee  ddoowwnnffiieelldd  HH‐‐66′′  11HH  NNMMRR  cchheemmiiccaall  sshhiiffttss  ooff  tthhee  ccaattaallyyssttss  ccoommppaarreedd  ttoo  tthhee  ccoorrrreessppoonnddiinngg  ffrreeee  
lliiggaannddss  ((TTaabbllee  11))..  IItt  iiss  aallssoo  sseeeenn  ffrroomm  tthhee  uupp‐‐ffiieelldd  11HH  NNMMRR  cchheemmiiccaall  sshhiifftt  ooff  tthhee  pprreeccaattaallyysstt  ccaarrbbeennee  
pprroottoonn  ((αα‐‐HH))  ccoommppaarreedd  ttoo  tthhaatt  ooff  GGrruubbbbss  22‐‐pprreeccaattaallyysstt..  TThhee  eelleeccttrroonn  ddoonnaattiioonn  ooff  tthhee  ppyyrriiddiinnyyll  
aallccoohhoollaattoo  nniittrrooggeenn  ttoo  tthhee  rruutthheenniiuumm  mmeettaall,,  dduurriinngg  cchheellaattiioonn,,  wwoouulldd  ppoossssiibbllyy  iinnccrreeaassee  tthhee  eelleeccttrroonn  
ddeennssiittyy  aarroouunndd  tthhee  rruutthheenniiuumm  aanndd  aallssoo  tthhee  bbeennzzyylliiddeennee  pprroottoonn..  TThhiiss  wwiillll  sshhiifftt  iittss  rreessoonnaannccee  uupp‐‐ffiieelldd  
ccoommppaarreedd  ttoo  tthhee  GGrruubbbbss  22‐‐pprreeccaattaallyysstt..  SSiimmuullttaanneeoouussllyy,,  tthhee  eelleeccttrroonn  ddeennssiittyy  oonn  tthhee  ppyyrriiddiinnyyll‐‐
aallccoohhoollaattoo  lliiggaanndd  nniittrrooggeenn  wwiillll  ddeeccrreeaassee,,  aanndd  tthhiiss  wwoouulldd  rreessuulltt  iinn  tthhee  ddoowwnnffiieelldd  cchheemmiiccaall  sshhiifftt  ooff  tthhee  
HH‐‐66′′  ooff  ppyyrriiddiinnee..  AA  ddoowwnnffiieelldd  cchheemmiiccaall  sshhiifftt  ooff  aa  pprroottoonn  iiss  iinnddiiccaattiivvee  ooff  tthhee  ddeeccrreeaassee  oonn  tthhee  eelleeccttrroonn
Catalysts 2017, 7, 22  4 of 21 
density around the atom [30]. Therefore, the chelation of the pyridinyl‐alcoholato ligands to the 
ruthenium metal is evident. The precatalysts 13–15 were all synthesized for the first time, as we did 
Catalysts2017,7,22 4of21
not find any reported in the literature. 
OLi N N
H IMes
2
N Cl Cl
THF,20-25°C,48 h
R Ph + Ru CHPh Ru CHPh
Cl O
PCy
3 (cid:2) N R = H (4)
R = H (9) 3 C R = 2-Cl (13)
R = 2-Cl (10) Ph R = 4-Cl (14)
R = 4-Cl (11) R R = 4-OMe (15)
R = 4-OMe (12)  
SScchheemmee 44.. SSyynntthheettiicc rreepprreesseennttaattiioonn ooff tthhee ssyynntthheessiiss ooff tthhee rruutthheenniiuumm-‐bbaasseedd pprreeccaattaallyyssttss.. 
TThabelen it1r.o gSeelnecctehde la1Hti oNnMofRt h(eNpucylreiadr inMyal-ganlectoich oRleastoonlaigncaen)d cshteomtihcael rushthiftesn iouf mthme estyanltchaensizbeed seen
fromptrheecadtaolywsntsfi, GelrdubHbs- 62(cid:48) a1nHd pNyMridRincyhl eamlcoichaollss. hifts of the catalysts compared to the corresponding
free ligands (Table 1). It is also seen from the up-field 1H NMR chemical shift of the precatalyst
Precatalyst  δα‐H (ppm) 1  δH‐6′ (ppm) 2  δH‐6′ (ppm) 3 
carbeneproton(α-H)comparedtothatofGrubbs2-precatalyst. Theelectrondonationofthepyridinyl
3 19.19 4  ‐  ‐ 
alcoholatonitrogentotherutheniummetal,duringchelation,wouldpossiblyincreasetheelectron
4 17.10  9.61  8.59 
densityaroundtherutheniumandalsothebenzylideneproton. Thiswillshiftitsresonanceup-field
13 17.34/17.26  9.76  8.55 
comparedtotheGrubbs2-precatalyst. Simultaneously,theelectrondensityonthepyridinyl-alcoholato
14 17.11/17.09  9.70–9.55  8.59 
ligandnitrogenwilldecrease, andthiswouldresultinthedownfieldchemicalshiftoftheH-6(cid:48) of
15 17.10/17.08  9.63–9.60  8.65 
pyridine. Adownfieldchemicalshiftofaprotonisindicativeofthedecreaseontheelectrondensity
1 1H NMR chemical shift of the precatalyst carbene proton (Ru = CH); 2 1H NMR chemical shift of the 
aroundtheatom[30]. Therefore,thechelationofthepyridinyl-alcoholatoligandstotheruthenium
pyridinyl methanolato ligand (C5H3N) H‐6′; 3 1H NMR chemical shift of the pyridinyl methanol 
metalisevident. Theprecatalysts13–15wereallsynthesizedforthefirsttime,aswedidnotfindany
(C5H3N) H‐6′; 4 obtained from [23]. 
reportedintheliterature.
The appearance of two peaks in the 1H NMR spectra of the precatalysts 13–15 is due to the 
chiraTliatbyl eof1 .thSee lpeyctreiddin1Hyl NaMlcoRho(Nlautcol elairgaMnadg naet titcheR eαso‐pnoansicteio)nc,h ewmhicicahl srheisftusltosf itnh ethsey nftohremsizaetidon of 
diastperreecoamtaleyrsst.s A,G sriumbbilsa2r apnhdenpyormideinnyolna licso ohboslse.rved in the 13C NMR spectra. 
2.3. Metathesis RPreeaccatitoanlyss t δα-H(ppm)1 δH-6(cid:48) (ppm)2 δH-6(cid:48) (ppm)3
The metathesi3s of 1‐octene resu1l9t.s1 9in4 a mixture of pr-oducts. The self‐me-tathesis of 1‐octene 
4 17.10 9.61 8.59
results in the formation of 7‐tetradecene (cis and trans) and ethene, named primary metathesis 
13 17.34/17.26 9.76 8.55
products (PMPs). T1h4e double bond1 i7n.1 11‐/o1c7t.e0n9e also unde9r.g70o–e9s. 5i5somerization to8 f.5o9rm internal olefins. 
The  isomerization1 5products  (IPs1)7 .1u0n/d1e7r.0g8o  self‐meta9t.h63e–s9is.6 0and  cross‐met8a.6th5esis  reactions  or 
second1a1rHyN mMeRtachthemesiciasl srheiaftcotfiothnesp ryeicealtadliynstgc atrhbeen veaprroiotouns( Raulk=eCnHe)s; 2in1H tNheM Rracnhegme icCal3–shCif1t6o nftahmepeydri dsiencyolndary 
metathmeestihsa nporloatdouligcatsn d(S(CM5HP3sN).) THa-6b(cid:48);le3 12H sNuMmRmchaermiziceasl sthhifet ovfathreiopuysri dmineytlamthetehsaniso lr(eCa5cHt3iNon)Hs -a6n(cid:48);d4o tbhtaei npedroducts 
from[23].
of 1‐octene in the presence of ruthenium alkylidene catalysts. 
Theappearanceoftwopeaksinthe1HNMRspectraoftheprecatalysts13–15isduetothechirality
Table 2. Summary of products of 1‐octene metathesis in the presence of ruthenium alkylidene 
ofthepyridinylalcoholatoligandattheα-position,whichresultsintheformationofdiastereomers.
precatalysts. PMPs (primary metathesis products); IPs (isomerization products); SMPs (secondary 
Asimilarphenomenonisobservedinthe13CNMRspectra.
metathesis products). 
2.3. MetathesisRReeaaccttiioonns Substrate 1 Products1 Abbreviation 
Primary metathesis  ‐  ‐  ‐ 
Themetathesisof1-octeneresultsinamixtureofproducts. Theself-metathesisof1-octeneresults
intheformatioSnelof‐fm7-etteattrhaedseicse ne(cisanCd=Ctr7a ns)andethene,Cn=aCm +e dCp7=rCim7 arymetathesisPpMroPdsu cts(PMPs).
ThedouIbsolembeornizdatinio1n- octenealsoundCer=gCo7e sisomerizCa2t=iCon6 +to Cf3o=rCm5 +in Cte4=rnCa4l olefins. ThIePsis omerization
Secondary metathesis 2  ‐  ‐  ‐ 
products(IPs)undergoself-metathesisandcross-metathesisreactionsorsecondarymetathesisreactions
Self‐metathesis  C2=C6  C2=C2 + C6=C6 
yieldingthevariousalkenesintherangeC3–C16namedsecondarymetathesisproductSsM(SPMs Ps).Table2
Cross‐metathesis  C=C7 + C2=C6 C2=C7 + C=C6 + C=C2 + C6=C7
summarizesthevariousmetathesisreactionsandtheproductsof1-octeneinthepresenceofruthenium
1 Hydrogens are omitted for simplicity; 2 only representative examples of SMPs are shown. 
alkylidenecatalysts.
Catalysts2017,7,22 5of21
Catalysts 2017, 7, 22  5 of 21 
Table 2. Summary of products of 1-octene metathesis in the presence of ruthenium alkylidene
precatalysts. PMPs(primarymetathesisproducts);IPs(isomerizationproducts);SMPs(secondary
2.3.1. Effect of Temperature on Catalyst Activity and Selectivity in 1‐Octene Metathesis 
metathesisproducts).
The effect of temperature on the catalytic activities of precatalysts 13–15 was investigated for 
temperaturRese aocft i7o0n, 80, 90, 100 anSdu b1s1t0r a°tCe.1 The results of theP rmodeutactthse1sis reaction ofA 1b‐borcetveinaeti ownith 13 
and 14P aritm 7a0r y°Cm eatraeth neosits included in th-e figures (Figures 1 and 2-) as a result of using dif-ferent time 
intervalsS eflofr-m seatmathpelsei scollection thaCn= Cth7ose of 80–110 °C. CA=C s+umC7m=Car7y of the resultsP, MhPoswever, is 
included Iisno mTearbizleasti o3n and 4. The metCa=thCe7sis of 1‐octenCe 2w=Cas6 a+lCso3 =pCe5rf+oCrm4=eCd4 using precaItPaslyst 4 at its 
Secondarymetathesis2 - - -
optimum  temperature  (80  °C)  with  the  intention  to  compare  it  with  the  newly‐synthesized 
Self-metathesis C =C C =C +C =C
2 6 2 2 6 6
precatalysts and to see the influence of the substituents on the catalytic activity. A comSpMarPisson of the 
Cross-metathesis C=C +C =C C =C +C=C +C=C +C =C
7 2 6 2 7 6 2 6 7
catalytic activity and selectivity of precatalysts 13–15 is also made with precatalysts 2–4 at their 
1Hydrogensareomittedforsimplicity;2onlyrepresentativeexamplesofSMPsareshown.
optimum temperatures. Furthermore stabilities of the precatalysts were compared in the temperature 
r2a.3n.g1e.sE 7ff0e–c1t1o0f °TCem. Tpheer aretusureltos nofC tahtea lmysettaAtchteivsiist yreaancdtioSnelse actriev pitryeisnen1t-eOdc bteenloewM. etathesis
The effect of temperature on the catalytic activities of precatalysts 13–15 was investigated for
Table 3. Summary of the catalytic activity of precatalyst 13 for the metathesis of 1‐octene after  
temperatures of 70, 80, 90, 100 and 110 ◦C. The results of the metathesis reaction of 1-octene with
540 min. 
13 and 14 at 70 ◦C are not included in the figures (Figures 1 and 2) as a result of using different
timTeeimnpte. rvalCsofnovr. 1s am1p‐Olectceonlel e2 ctioPnMtPhsa 2n  thoIPsse 2 of8S0M–P1s1 02 ◦C.SA 3  summKaIrn y4 oftheTOreNs u5 lts,hoTwOFe 6v er,is
(°C)  (%) 
includedinTables3and4. Themetathesisof1-octenewasalsoperformedusingprecatalyst4atits
70  25  75  22.7  0.3  2.0  90.8  4.35 × 10−3  2039  6.3 × 10−2 
optim80u mtemp4e6r ature(805◦4C  )witht4h4e.2i ntentio0.n1 tocom1.9p areit9w5.7i thth7e.4n0 e×w 10l−y3 -synt3h9e82s ized1p2r.3e c×a 1t0a−l2 ysts
and t9o0 see the9i4n fluence o6f  the subs7t1i.7tu  ents1o.n3 the c2a0.t7a lytic7a6.c6t ivit1y4..8A4 ×c 1o0m−3 par6is4o56n  of t1h9e.9 c×a 1t0a−l2 ytic
100  95  5  69.4  1.5  24.4  72.8  9.48 × 10−3  6242  19.3 × 10−2 
activity and selectivity of precatalysts 13–15 is also made with precatalysts 2–4 at their optimum
110  97  3  64.7  1.9  30.2  66.8  12.86 × 10−3 5824  18.0 × 10−2 
temperatures. Furthermorestabilitiesoftheprecatalystswerecomparedinthetemperatureranges
1 Conversion; 2 yield in mol % and Ru/1‐octene molar ratio 1:9000; 3 selectivity in percent toward PMPs; 
70–110◦C.Theresultsofthemetathesisreactionsarepresentedbelow.
4 initiation constant in mol/s; 5 turnover number (TON) = (n%PMPs × [nOct]/[nRu])/100 (Oct = 1‐
octene); 6 turnover frequency (TOF) = TON/s. 
Table3.Summaryofthecatalyticactivityofprecatalyst13forthemetathesisof1-octeneafter540min.
Precatalyst 13 showed a progressive activity in 1‐octene metathesis in the temperature range of 
Temp.(◦C) Conv.1(%) 1-Octene2 PMPs2 IPs2 SMPs2 S3 KIn4 TON5 TOF6
70–110 °C (Table 3 and Figure 1). The activity of 13, however, is very slow at 70 °C, resulting only in 
70 25 75 22.7 0.3 2.0 90.8 4.35×10−3 2039 6.3×10−2
25% c8o0nversion o46f 1‐octene 5t4o 22.7%4 4P.2MPs, 02.1.0% SM1.9Ps and95 .70.3% 7.I4P0s× i1n0 −5340 m3i9n82. Alt1h2o.3u×gh10 −th2e 
selecti9v0ity  is  goo9d4  (91%),  t6he  initia7t1io.7n  con1s.3tant  (2K0I.n7),  tur7n6.o6ver 14n.8u4m×b1e0−r 3(TO6N45)6  and1 9.t9u×rn1o0−v2er 
100 95 5 69.4 1.5 24.4 72.8 9.48×10−3 6242 19.3×10−2
frequency (TOF) are low. The activity, however, was almost doubled on increasing the reaction 
110 97 3 64.7 1.9 30.2 66.8 12.86×10−3 5824 18.0×10−2
temperature to 80 °C, resulting in 46% conversion of 1‐octene to 44.2% PMPs, 1.9% SMPs and  
1 Conversion;2 yieldinmol%andRu/1-octenemolarratio1:9000;3 selectivityinpercenttowardPMPs;
1.1% IP4sin. itTiahtieon sceolnesctatinvtiitnym aoll/sos; 5intucrrneoavseerdn utmob e9r6(%TO, Nr)e=su(nl%tinPMg Pisn× a[ nOsicgt]n/i[fniRcaun])t/ 1i0n0c(rOecats=e1 -ionc teKnIen),; TON  
and TO6Ftu. rnoverfrequency(TOF)=TON/s.
100 100
80 80
%) 60 %) 60
ne ( s (
e P
Oct 40 PM 40
1-
20 20
0 0
0 100 200 300 400 500 600 0 100 200 300 400 500 600
Reaction time (min) Reaction time (min)
(a) (b)
Figure1.Cont.
Catalysts 2017, 7, 22  7 of 21 
Table 4. Summary of the catalytic activity of precatalyst 14 for the metathesis of 1‐octene after  
540 min. 
Temp  Conv. 1 
1‐Octene 2  PMPs 2  IPs 2  SMPs 2  S 3  KIn 4  TON 5  TOF 6 
(°C)  (%) 
70  6  94  5.3  0.1  0.8  86  0.71 × 10−3  476  1.57 × 10−2 
80  59  41  56.6  0.2  2.4  96  9.22 × 10−3  5097  15.7 × 10−2 
90  82  18  75.8  0.2  5.8  93  11.36 × 10−3  6823  21.1 × 10−2 
100  79  21  77.0  0.4  2.0  97  14.11 × 10−3  6928  21.4 × 10−2 
110  87  13  81.1  0.5  5.0  94  12.75 × 10−3  7298  22.5 × 10−2 
1 Conversion; 2 yield in mol % and Ru/1‐octene molar ratio 1:9000; 3 selectivity in percent toward PMPs; 
4 initiation constant in mol/s; 5 TON = (n%PMPs × [nOct]/[nRu])/100; 6 TOF = TON/s. 
After 3570 min at 70 °C, 66% of the 1‐octene was converted to 65% PMPs, 0.8% SMPs and  
0.2% IPs with 99% selectivity, 5854 TON and 2.60 × 10−2 TOF. Although the 1‐octene conversion, PMP 
formation, selectivity and TON increased significantly, the rate of the reaction is very slow. The 
selectivity (99%) towards PMP formation, however, is excellent at this temperature. This therefore 
shows the need for increasing the reaction temperature in order to increase the activity of the 
Catpalryesctsa2ta01ly7,s7t ,a2n2d increase the rate of product formation. The reaction temperature was raised to 80 6°Cof 21
Cataalnydst sr 2e0s1u7l,t 7e,d 2 2in   59% 1‐octene conversion to 56.6% PMPs, 5.8% SMPs and 0.2% IPs with 96% selectiv6it oyf,  21 
rel5a0tively high KIn (9.22 × 10−3), TON (5097) and TOF (152..57 × 10−2) after 540 min (Table 4). The 1‐octene 
conversion and PMP formation increased ten‐fold, while the SMPs and IPs increased only two‐fold 
in 540 min. A very large increase in selectivity, initiation constant, TON and TOF is also observed. 
40 2.0
The reaction reached equilibrium after 1620 min with 84% 1‐octene conversion to 81.2% PMPs,  
2.3% SMPs and 0.28% IPs with 97% selectivity, 7307 TON and 7.5 × 10−2 TOF. Further increasing the 
Ps (%)twemi3t0hp 9e3ra%tu sreel etcot i9v0it y°C, 6 r8e2s3u TltOedN i,n 1 18.23%6 × 1 1‐o0c−3t eKnIne  acnodn s (%)v21e.r1s1 i.×o5 n10 t−o2  T7O5.F8.% A PltMhoPusg, h5 .a8l%l o Sf MthPe sf aacntodr s0 .(2e%xc eIPpst  
SMsel2e0ctivity) showed an increase upon raising the temIPper1a.0ture to 90 °C, further raising the temperature 
to 100 °C only increased the PMPs (77%), selectivity (97%), TON (6928), KIn (14.11 × 10−3) and TOF 
(21.4 × 10−2). The 1‐octene conversion (79%), SMPs (2.0%) and IPs (0.4%), however, decreased 
10 0.5
moderately. The reaction attained equilibrium at 660 min (Figure 2) with 84% 1‐octene conversion to 
78.5% PMPs, 5.5% SMPs, 0.2% IPs, 93% selectivity, 7068 TON and 17.9 × 10−2 TOF at 90 °C. It required 
0 0
only 0420 m1in00 to re2a0c0h equ3i0l0ibrium40 0at 1005 0°0C (Fi6g0u0re 2) wit0h 79%1 010‐octen20e0 conv3e0r0sion t4o0 075.8%50 P0MPs6,0 0
2.5% SMPs, 0.3 IPsR aenacdt io9n7 %tim see (lmecinti)vity, 6825 TON and 27.08 × 10−2 TOFR. eAact t1io1n0 t i°mCe,  (hmoinw)ever, 87% of 
the 1‐octene was convert(ecd) to 81.1% PMPs, 5.0% SMPs, 0.5% IP with 94% s(edl)ectivity, 7298 TON,  
12.F7i5g u× r1e0 −13.  KTIhn ea nindf l2u2e.n5c ×e  1o0f− 2t eTmOpFe arat t5u4r0e  monin t.h Te hree a1c‐toioctne ncoem copnovsietriosino nd,u PriMngP  manedta tShMesPis f oorf m1‐aotciotenn ea nd 
Figure1.Theinfluenceoftemperatureonthereactioncompositionduringmetathesisof1-octeneusing
TON showed a significant increase compared to that at 100 °C. Although the reaction seems to 
using the ruthenium alkylidene precatalyst 13: (a) conversion of 1‐octene; (b) formation of PMPs 
therutheniumalkylideneprecatalyst13:(a)conversionof1-octene;(b)formationofPMPs(primary
equilibrate at 200 min at 110 °C, the reaction slowly continued showing an increase in the substrate 
(primary metathesis products); (c) formation of SMPs (secondary metathesis products); (d) formation 
metathesisproducts);(c)formationofSMPs(secondarymetathesisproducts);(d)formationofIPs
conversion, PMP, SMP and IP formation up to 540 min (Figure 2). Considering all of the factors, 
o(ifs IoPms e(irsizoamtieornizpartioodnu pctrso)d;Rucut/s)1;- Rocut/e1n‐eoc(t1e:9n0e0 (01):9(0(cid:4)0,08)0 (■◦,C 8;0(cid:78) °,C9;0 ▲◦C, 9;0(cid:7) ,°C10; 0♦◦, C10;0(cid:3) °,C1;1 □0,◦ 1C1)0. °C). 
therefore, the optimum temperature for 1‐octene metathesis using precatalyst 14 is 100 °C. 
R1e0l0atively large conversion (94%) of the 1‐octen1e0 0into the various products was observed at  
90 °C. This, however, resulted in an enormous increase in the SMPs (20.7%) and PMPs (71.7%). The 
IPs (1.2860%) showed a very small increase as a result of t8h0e fast conversion to SMPs. A decrease in the 
selectivity (77%) and a large increase in the initiation constant, TON and TOF are observed due to 
hig%)h co6n0version of 1‐octene to PMPs and SMPs. T%)he 60increase in substrate conversion at 100 and  
110ene ( °C is not significant and led to a slight increasePs ( in SMPs (24.4% and 30.2%, respectively) and IPs 
(1.5Oct% a4n0d 1.9%, respectively).  PM 40
1-A decrease in the selectivity, KIn, TON and TOF was observed due to the slow 1‐octene 
convers2i0on. As a result of a very low activity at 70 °C, th20e reaction reached equilibrium, i.e., when no 
further PMP formation is observed, at 3630 min, wherein 85% 1‐octene conversion to 80% PMPs, 4.9% 
SMPs an0d 0.2% IPs with 94% selectivity, 7214 TON and0 3.3 × 10−2 TOF were observed. On the other 
hand, at 800 °C,1 0e0quili2b0r0ium 3w00as at4t0a0ined5 a00t 210600 0min and0 79%1 100‐octe2n0e0 con3v0e0rsion40 0resul5t0in0g in6 0609% 
Reaction time (min) Reaction time (min)
PMCaPtasl,y s9ts.4 2%01 7S, 7M, 2P2 s, and 0.2% IPs with 88% selectivity, 6237 TON and 4.94 × 10−2 TOF. At 90 8° Cof, 2 t1h e 
(a) (b)
reaction attained equilibrium at 350 min and 94% 1‐octene conversion into 73.4% PMPs, 19.4% SMPs 
10 2.5
an d 1.1% IPs with 78% selectivity, 6606 TON and 31.5 × 10−2 TOF. Although equilibrium was attained 
at 140 min at 100 and 110 °C, the 1‐octene conversion and product distribution showed significant 
8 2.0
variation. At 100 °C, 86% conversion of 1‐octene into 73% PMPs, 12.3% SMPs and 0.7% IPs was 
observed with 84% selectivity, 6523 TON and 77.7 × 10−2 TOF. In the case of 110 °C, 94% of 1‐octene 
w76a.9sMPs (%)  ×c o1n06−v2e TrtOedF.  Ainlttoh o7u2g%h  tPhMe Phsig, h2e1s%t s eSlMecPtisv iatyn dan Ps (%)1d. 2la%1.r5 gIeP Ps MwPi tfho r7m6%ati osnel aecntdiv TitOy,N 6 w45i6th  TrOelNat ivaenldy   
S 4 I 1.0
low SMP and IP formation are observed at 70 °C, it took a very long time to reach equilibrium. 
Considering the rate of the reaction, high PMPs, low SMPs and IPs, the optimum temperature for the 
2 0.5
precatalyst 13 is 80 °C. 
The catalytic activity of precatalyst 14 is summarized in Table 4 and Figure 2. A very low 
0 0
conversio0n of 1100‐octe2n0e0 (6%30) 0to P4M00Ps (550.03%), 60S0MPs (0.08%) a10n0d IP2s0 0(0.1%30)0 with40 086% 50s0electi6v00ity,  
Reaction time (min) Reaction time (min)
476 TON, 0.71 × 10−3 KIn and 1.47 × 10−2 TOF is observed for 1‐octene metathesis. The reaction did not 
(c) (d)
even reach equilibrium after 3570 min, at which point, the reaction was stopped. 
  FiFgiugruere2 .2T. Thheei ninflfulueennccee ooff tteemm ppeerraattuurree oonn tthhee rreeaaccttiioonn ccoommppoossitiitoionn dduurirnign gmmeteattahtehseiss iosf o1f‐o1c-toecntee ne
using the ruthenium alkylidene precatalyst 14: (a) conversion of 1‐octene; (b) formation of PMPs;  
usingtherutheniumalkylideneprecatalyst14: (a)conversionof1-octene; (b)formationofPMPs;
(c)(cf)o fromrmataiotinono offS SMMPPss;; ((dd)) ffoorrmmaattiioonn ooff IIPPss; ;RRuu/1/‐o1c-otecnteen (e1:9(10:0900)0 (0■), (8(cid:4)0 ,°8C0; ▲◦C, ;9(cid:78)0 ,°C90; ♦◦,C 1;0(cid:7)0 ,°1C0; 0□,◦ C  ;
(cid:3),11110 0°C◦C). ).
Figure 3 and Table 5 summarize the influence of temperature on the 1‐octene metathesis reaction 
using precatalyst 15 after 540 min. As was the case with precatalysts 13 and 14, the 1‐octene 
metathesis reaction using precatalyst 15 showed relatively low substrate conversion, PMP, IP and 
SMP formation and KIn, TON and TOF after 540 min. Generally, it showed low activity. 
At 70 °C, the reaction did not reach equilibrium after 2100 min, resulting in 47% 1‐octene 
conversion to 45% PMPs, 1.7% SMPs, 0.2% IPs and 96% selectivity, 4032 TON, 3.29 × 10−2 TOF. 
Increasing the temperature to 80 °C raised the 1‐octene conversion to 32%, resulting in 53.4% PMPs, 
1.4% SMPs, 0.2% IP and 95% selectivity, 2765 TON, 4.46 × 10−3 KIn and 8.5 × 10−2 TOF after 540 min. 
The substrate conversion and PMP formation, KIn, TON and TOF are doubled, while the SMP 
formation showed a moderate increase, and IP formation decreased. The reaction did not equilibrate 
after  2100  min,  resulting  in  84%  1‐octene  conversion  to  81%  PMPs,  2.9%  SMPs,  0.1%  IPs,  
97% selectivity, 7321 TON and 5.8 × 10−2 TOF. Raising the temperature to 90 °C converted 56% of  
1‐octene to 53.4% PMPs, 2.1% SMPs, 0.2% IPs and 96% selectivity, 4802 TON, 7.74 × 10−3 KIn and  
14.8 × 10−2 TOF after 450 min. Except for IP formation and selectivity, a substantial increase was 
observed in all of the factors upon increasing the temperature by 10 °C.
Catalysts2017,7,22 7of21
Table4.Summaryofthecatalyticactivityofprecatalyst14forthemetathesisof1-octeneafter540min.
Temp(◦C) Conv.1(%) 1-Octene2 PMPs2 IPs2 SMPs2 S3 KIn4 TON5 TOF6
70 6 94 5.3 0.1 0.8 86 0.71×10−3 476 1.57×10−2
80 59 41 56.6 0.2 2.4 96 9.22×10−3 5097 15.7×10−2
90 82 18 75.8 0.2 5.8 93 11.36×10−3 6823 21.1×10−2
100 79 21 77.0 0.4 2.0 97 14.11×10−3 6928 21.4×10−2
110 87 13 81.1 0.5 5.0 94 12.75×10−3 7298 22.5×10−2
1 Conversion;2 yieldinmol%andRu/1-octenemolarratio1:9000;3 selectivityinpercenttowardPMPs;
4initiationconstantinmol/s;5TON=(n%PMPs×[nOct]/[nRu])/100;6TOF=TON/s.
Precatalyst13showedaprogressiveactivityin1-octenemetathesisinthetemperaturerangeof
70–110◦C(Table3andFigure1). Theactivityof13,however,isveryslowat70◦C,resultingonly
in 25% conversion of 1-octene to 22.7% PMPs, 2.0% SMPs and 0.3% IPs in 540 min. Although the
selectivityisgood(91%),theinitiationconstant(K ),turnovernumber(TON)andturnoverfrequency
In
(TOF)arelow. Theactivity,however,wasalmostdoubledonincreasingthereactiontemperatureto
80◦C,resultingin46%conversionof1-octeneto44.2%PMPs,1.9%SMPsand1.1%IPs. Theselectivity
alsoincreasedto96%,resultinginasignificantincreaseinK ,TONandTOF.
In
Relativelylargeconversion(94%)ofthe1-octeneintothevariousproductswasobservedat90◦C.
This, however, resulted in an enormous increase in the SMPs (20.7%) and PMPs (71.7%). The IPs
(1.26%)showedaverysmallincreaseasaresultofthefastconversiontoSMPs. Adecreaseinthe
selectivity(77%)andalargeincreaseintheinitiationconstant,TONandTOFareobservedduetohigh
conversionof1-octenetoPMPsandSMPs. Theincreaseinsubstrateconversionat100and110◦Cis
notsignificantandledtoaslightincreaseinSMPs(24.4%and30.2%,respectively)andIPs(1.5%and
1.9%,respectively).
Adecreaseintheselectivity,K ,TONandTOFwasobservedduetotheslow1-octeneconversion.
In
Asaresultofaverylowactivityat70◦C,thereactionreachedequilibrium,i.e.,whennofurtherPMP
formationisobserved,at3630min,wherein85%1-octeneconversionto80%PMPs,4.9%SMPsand
0.2%IPswith94%selectivity,7214TONand3.3×10−2 TOFwereobserved. Ontheotherhand,at
80 ◦C, equilibrium was attained at 2100 min and 79% 1-octene conversion resulting in 69% PMPs,
9.4%SMPs,and0.2%IPswith88%selectivity,6237TONand4.94×10−2TOF.At90◦C,thereaction
attainedequilibriumat350minand94%1-octeneconversioninto73.4%PMPs,19.4%SMPsand1.1%
IPswith78%selectivity,6606TONand31.5×10−2TOF.Althoughequilibriumwasattainedat140min
at 100 and 110 ◦C, the 1-octene conversion and product distribution showed significant variation.
At100◦C,86%conversionof1-octeneinto73%PMPs,12.3%SMPsand0.7%IPswasobservedwith
84%selectivity,6523TONand77.7×10−2TOF.Inthecaseof110◦C,94%of1-octenewasconverted
into72%PMPs,21%SMPsand1.2%IPswith76%selectivity,6456TONand76.9×10−2TOF.Although
thehighestselectivityandlargePMPformationandTONwithrelativelylowSMPandIPformation
areobservedat70◦C,ittookaverylongtimetoreachequilibrium.Consideringtherateofthereaction,
highPMPs,lowSMPsandIPs,theoptimumtemperaturefortheprecatalyst13is80◦C.
The catalytic activity of precatalyst 14 is summarized in Table 4 and Figure 2. A very low
conversionof1-octene(6%)toPMPs(5.3%),SMPs(0.8%)andIPs(0.1%)with86%selectivity,476TON,
0.71×10−3K and1.47×10−2TOFisobservedfor1-octenemetathesis. Thereactiondidnoteven
In
reachequilibriumafter3570min,atwhichpoint,thereactionwasstopped.
After3570minat70◦C,66%ofthe1-octenewasconvertedto65%PMPs,0.8%SMPsand0.2%IPs
with99%selectivity,5854TONand2.60×10−2TOF.Althoughthe1-octeneconversion,PMPformation,
selectivityandTONincreasedsignificantly,therateofthereactionisveryslow. Theselectivity(99%)
towardsPMPformation,however,isexcellentatthistemperature. Thisthereforeshowstheneedfor
increasingthereactiontemperatureinordertoincreasetheactivityoftheprecatalystandincrease
the rate of product formation. The reaction temperature was raised to 80 ◦C and resulted in 59%
1-octeneconversionto56.6%PMPs,5.8%SMPsand0.2%IPswith96%selectivity,relativelyhighK
In
(9.22 × 10−3),TON(5097)andTOF(15.7 × 10−2)after540min(Table4). The1-octeneconversion
Catalysts2017,7,22 8of21
andPMPformationincreasedten-fold,whiletheSMPsandIPsincreasedonlytwo-foldin540min.
Averylargeincreaseinselectivity,initiationconstant,TONandTOFisalsoobserved. Thereaction
reachedequilibriumafter1620minwith84%1-octeneconversionto81.2%PMPs, 2.3%SMPsand
0.28%IPswith97%selectivity,7307TONand7.5 × 10−2 TOF.Furtherincreasingthetemperature
to 90 ◦C resulted in 82% 1-octene conversion to 75.8% PMPs, 5.8% SMPs and 0.2% IPs with 93%
selectivity, 6823 TON, 11.36 × 10−3 K and 21.1 × 10−2 TOF. Although all of the factors (except
In
selectivity)showedanincreaseuponraisingthetemperatureto90◦C,furtherraisingthetemperature
to100◦ConlyincreasedthePMPs(77%),selectivity(97%),TON(6928),K (14.11×10−3)andTOF
In
(21.4 × 10−2). The 1-octene conversion (79%), SMPs (2.0%) and IPs (0.4%), however, decreased
moderately. Thereactionattainedequilibriumat660min(Figure2)with84%1-octeneconversionto
78.5%PMPs,5.5%SMPs,0.2%IPs,93%selectivity,7068TONand17.9×10−2TOFat90◦C.Itrequired
only420mintoreachequilibriumat100◦C(Figure2)with79%1-octeneconversionto75.8%PMPs,
2.5%SMPs,0.3IPsand97%selectivity,6825TONand27.08×10−2 TOF.At110◦C,however,87%
ofthe1-octenewasconvertedto81.1%PMPs,5.0%SMPs,0.5%IPwith94%selectivity,7298TON,
12.75×10−3K and22.5×10−2TOFat540min. The1-octeneconversion,PMPandSMPformation
In
andTONshowedasignificantincreasecomparedtothatat100◦C.Althoughthereactionseemsto
equilibrateat200minat110◦C,thereactionslowlycontinuedshowinganincreaseinthesubstrate
conversion, PMP, SMP and IP formation up to 540 min (Figure 2). Considering all of the factors,
therefore,theoptimumtemperaturefor1-octenemetathesisusingprecatalyst14is100◦C.
Figure3andTable5summarizetheinfluenceoftemperatureonthe1-octenemetathesisreaction
usingprecatalyst15after540min. Aswasthecasewithprecatalysts13and14,the1-octenemetathesis
reactionusingprecatalyst15showedrelativelylowsubstrateconversion,PMP,IPandSMPformation
andK ,TONandTOFafter540min. Generally,itshowedlowactivity.
In
Table5.Summaryofthecatalyticactivityofprecatalyst15forthemetathesisof1-octeneafter540min.
Temp(◦C) Conv.1(%) 1-Octene2 PMPs2 IPs2 SMPs2 S3 KIn4 TON5 TOF6
70 17 83 15.4 0.2 1.3 91 1.82×10−3 1387 4.3×10−2
80 32 68 30.7 0.2 1.4 95 4.46×10−3 2765 8.5×10−2
90 56 44 53.4 0.2 2.1 96 7.74×10−3 4802 14.8×10−2
100 75 25 71.9 0.3 2.5 96 12.83×10−3 6469 20.0×10−2
110 97 3 91.8 0.3 4.5 95 19.01×10−3 8264 25.5×10−2
1 Conversion;2 yieldinmol%andRu/1-octenemolarratio1:9000;3 selectivityinpercenttowardPMPs;
4initiationconstantinmol/s;5TON=(n%PMPs×[nOct]/[nRu])/100;6TOF=TON/s.
At 70 ◦C, the reaction did not reach equilibrium after 2100 min, resulting in 47% 1-octene
conversion to 45% PMPs, 1.7% SMPs, 0.2% IPs and 96% selectivity, 4032 TON, 3.29 × 10−2 TOF.
Increasingthetemperatureto80◦Craisedthe1-octeneconversionto32%,resultingin53.4%PMPs,
1.4% SMPs, 0.2% IP and 95% selectivity, 2765 TON, 4.46 × 10−3 K and 8.5 × 10−2 TOF after 540
In
min. ThesubstrateconversionandPMPformation,K ,TONandTOFaredoubled,whiletheSMP
In
formationshowedamoderateincrease,andIPformationdecreased. Thereactiondidnotequilibrate
after2100min,resultingin84%1-octeneconversionto81%PMPs,2.9%SMPs,0.1%IPs,97%selectivity,
7321TONand5.8×10−2TOF.Raisingthetemperatureto90◦Cconverted56%of1-octeneto53.4%
PMPs, 2.1% SMPs, 0.2% IPs and 96% selectivity, 4802 TON, 7.74 × 10−3 K and 14.8 × 10−2 TOF
In
after450min. ExceptforIPformationandselectivity,asubstantialincreasewasobservedinallofthe
factorsuponincreasingthetemperatureby10◦C.
Catalysts 2017, 7, 22  9 of 21 
Table 5. Summary of the catalytic activity of precatalyst 15 for the metathesis of 1‐octene after  
540 min. 
Temp  Conv. 1 
(°C)  (%)  1‐Octene 2  PMPs 2  IPs 2  SMPs 2  S 3  KIn 4  TON 5  TOF 6 
70  17  83  15.4  0.2  1.3  91  1.82 × 10−3  1387  4.3 × 10−2 
80  32  68  30.7  0.2  1.4  95  4.46 × 10−3  2765  8.5 × 10−2 
90  56  44  53.4  0.2  2.1  96  7.74 × 10−3  4802  14.8 × 10−2 
100  75  25  71.9  0.3  2.5  96  12.83 × 10−3  6469  20.0 × 10−2 
110  97  3  91.8  0.3  4.5  95  19.01 × 10−3  8264  25.5 × 10−2 
Catalysts2011 C7,o7n,v2e2rsion; 2 yield in mol % and Ru/1‐octene molar ratio 1:9000; 3 selectivity in percent toward PMPs;  9of21
4 initiation constant in mol/s; 5 TON = (n%PMPs × [nOct]/[nRu])/100; 6 TOF = TON/s. 
100 100
80 80
ne (%) 60 s (%) 60
e P
Oct 40 PM 40
1-
20 20
0 0
0 100 200 300 400 500 600 0 100 200 300 400 500 600
Reaction time (min) Reaction time (min)
(a) (b)
10 2.5
8 2.0
Ps (%) 6 s (%) 1.5
M P
S 4 I 1.0
2 0.5
0 0
0 100 200 300 400 500 600 0 100 200 300 400 500 600
Reaction time (min) Reaction time (min)
(c) (d)
Figure 3. The influence of temperature on the reaction composition during metathesis of 1‐octene 
Figure3. Theinfluenceoftemperatureonthereactioncompositionduringmetathesisof1-octene
using the ruthenium alkylidene precatalyst 15: (a) conversion of 1‐octene; (b) formation of PMPs;  
usingtherutheniumalkylideneprecatalyst15: (a)conversionof1-octene; (b)formationofPMPs;
(c) formation of SMPs; (d) formation of IPs; Ru/1‐octene (1:9000) (●, 70 °C; ■, 80 °C; ▲, 90 °C; ♦, 100 °C; 
(c)formationofSMPs;(d)formationofIPs;Ru/1-octene(1:9000)( ,70◦C;(cid:4),80◦C;(cid:78),90◦C;(cid:7),100◦C;
□, 110 °C). 
(cid:3),110◦C).
The reaction, however, did not reach equilibrium at 2100 min, where it was stopped, resulting 
inT h9e1%re acocntivoenr,sihoonw ofe v1‐eorc,tdenide ntoo t87r%ea cPhMePqsu, 4il.i1b%ri uSMmPast, 02.120%0 ImPsi,n 9,5w%h seerleecittivwitays, s7t8o3p5 pTeOdN,r aensud lt ing
in 916%.2 c×o 1n0v−2e rTsOioFn. Rofel1a-tiovcetleyn heigtoh 8s7u%bstPraMteP cso,n4v.1e%rsioSnM tPos h,i0g.h2 %PMIPPss, 9an5d% SsMelPesc tiisv iotyb,se7r8v3e5d TaOfteNr a nd
6.2 ×210100 −m2inT. OAtF 1.0R0 e°lCa,t i7v5e%ly ofh thigeh 1‐souctbesnter awteasc coonnvveerrtseido nto t7o1.h9%ig PhMPPMs,P 2s.5%an SdMSPMs aPnsd i0s.3o%b IsPesr vweidth after
210096m%in s.elAecttiv10it0y, ◦6C46,97 5T%ONo,f 1t2h.8e3 1×- o10c−t3e KnIen awnads 2c0o.0n ×v 1e0r−t2e TdOtFo a7f1te.r9 %540P mMinP.s T,h2e.5 i%ncrSeMasPe sina 1n‐doct0e.n3e%  IPs
conversion to PMPs is significant, while its conversion to SMPs and IPs is relatively small. The TON, 
with96%selectivity,6469TON,12.83×10−3K and20.0×10−2TOFafter540min. Theincreasein
KIn and TOF also showed a substantial increasIen. The reaction, however, reached equilibrium after  
1-octeneconversiontoPMPsissignificant,whileitsconversiontoSMPsandIPsisrelativelysmall.
780 min with 84% of substrate conversion to 81% PMPs, 3.5% SMPs, 0.3% IPs, 96% selectivity,  
TheT72O5N1 T,OKNIn aanndd 1T5O.5F × a1l0s−o2 TshOoFw. Iend spaitseu obfs atalln otfi atlhien vcarreiaastieo.nTsh ine sreuabcsttiroante, choonwveervseior,nr,e PaMchPe, dSMeqPu ailnidb rium
after780minwith84%ofsubstrateconversionto81%PMPs,3.5%SMPs,0.3%IPs,96%selectivity,
7251 TONand15.5×10−2TOF.Inspiteofallofthevariationsinsubstrateconversion,PMP,SMPand
IPformation,theselectivityremainedthesame(96%),whichisaremarkablephenomenon. Asaresult
oftherelativelysmallSMPandIPformation,wewereinterestedtoseetheinfluenceofthereaction
temperatureat110◦Conthecatalyticperformanceof15. AsisshowninTable5andFigure3,97%
ofthe1-octenewasconvertedto91.8%PMPs,4.5%SMPs,0.3%IPswith95%selectivity,8264TON,
19.01×10−3 K and26.0×10−2 TOFafter540min. Thisisaremarkableresult,whichwedidnot
In
seewithanyofthepreviousprecatalystsatthistemperatureafter540min. Inadditiontothis,the
reactionattainedequilibriumafter660minwith97%ofthesubstratebeingconvertedto93%PMPs,
4.3%SMPs,0.2%IPswith95%selectivity,8340TONand21.1×10−2TOF.Itisexcitingtoseenearly
allofthe1-octenebeingconvertedtoPMPs. Itisdifficulttodecidetheoptimumreactiontemperature
forprecatalyst15asaresultofsimilarselectivitiestowardsPMPsatthehightemperatures. Therefore,
weprefertoconsiderboth100and110◦Casoptimumtemperaturesforprecatalyst15.
Catalysts2017,7,22 10of21
2.3.2. ComparisonofCatalyticActivityandSelectivity
Table6andFigure4showasummaryandcomparisonrespectivelyofthecatalyticactivitiesof
precatalysts2–4and13–15in1-octenemetathesisat80◦Cafter540min. Wechoose80◦Cbecausethe
optimumtemperatureforprecatalyst4,ourreferenceprecatalyst,is80◦C,asitwillhelpuscompare
theinfluenceofthesubstituentsonthecatalyticactivitiesofprecatalysts13–15. Wealsoincludedthe
firstandsecondgenerationGrubbsprecatalysts2and3forthesakeofcomparingtheimprovementin
termsofthecatalystactivityathightemperatures. Aswehavementionedearlier,ourmainobjectiveis
tosynthesizeacatalystthatwouldperformbetterathightemperaturessothatitcouldbeconsidered
forindustrialapplications.
Table6. Summaryofthecatalyticactivityofdifferentprecatalystsforthemetathesisof1-octeneat
540minand80◦C.
Catalyst Conv.1(%) 1-octene2 PMPs2 IPs2 SMPs2 S3 KIn4 TON5 TOF6
2 83.2 16.8 58.0 25.2 0.5 69 9.36×10−3 5179 16.0×10−2
3 96 4.0 67.0 3.0 26.0 70 7.91×10−3 6029 18.6×10−2
4 77 23.2 74.0 2.7 0.2 96 10.66×10−3 6643 20.5×10−2
13 46 53.7 44.0 1.9 0.1 96 7.40×10−3 3982 12.3×10−2
14 59 40.8 57.0 2.3 0.2 96 9.22×10−3 5097 15.7×10−2
15 32 68.0 31.0 1.4 0.2 95 4.46×10−3 2765 8.5×10−2
1 Conversion;2 yieldinmol%andRu/1-octenemolarratio1:9000;3 selectivityinpercenttowardPMPs;
4initiationconstantinmol/s;5TON=(n%PMPs×[nOct]/[nRu])/100;6TOF=TON/s.
Catalysts 2017, 7, 22  11 of 21 
100 100
80 80
ne (%) 60 s (%) 60
e P
Oct 40 PM 40
1-
20 20
0 0
0 100 200 300 400 500 600 0 100 200 300 400 500 600
Reaction time (min) Reaction time (min)
(a) (b)
10 2.5
8 2.0
Ps (%) 6 s (%) 1.5
M P
S 4 I 1.0
2 0.5
0 0
0 100 200 300 400 500 600 0 100 200 300 400 500 600
Reaction time (min) Reaction time (min)
(c) (d)
Figure 4. Comparison of catalytic activity, selectivity and stability of precatalysts 4 and 13–15 during 
Figure4.Comparisonofcatalyticactivity,selectivityandstabilityofprecatalysts4and13–15during
the course of metathesis of 1‐octene: (a) conversion of 1‐octene; (b) formation of PMPs; (c) formation 
thecourseofmetathesisof1-octene:(a)conversionof1-octene;(b)formationofPMPs;(c)formationof
of SMPs; (d) formation of IPs; Ru/1‐octene (1:9000), 80 °C (●, 4; ■, 13; ▲, 14; ♦, 15). 
SMPs;(d)formationofIPs;Ru/1-octene(1:9000),80◦C( ,4;(cid:4),13;(cid:78),14;(cid:7),15).
The lowest catalytic activity is observed for 13 in every aspect (except selectivity), and the highest 
selectivity is observed for 2. The highest substrate conversion and PMPs formation is observed for 15 
(at 110 °C), which is followed by 3. Precatalyst 3, however, resulted in relatively high TON and TOF 
followed by 15 (at 110 °C). Precatalysts 15 (at 100 °C) and 4 showed similar activities, whereas 
precatalyst 14 showed better activity than these two. Generally, precatalysts 14 and 15 showed better 
activity than the rest of the precatalysts at high temperatures (100 and 110 °C). Therefore, we 
improved the optimum temperature of the very stable precatalyst 4 to temperatures as high as  
100 and 110 °C, sustaining high catalyst activity and selectivity by introducing chloro and methoxy 
groups on the p‐position of one of the α‐phenyl groups in the pyridinyl alcoholato ligand. 
Table 7. Summary of the catalytic activity of different precatalysts for the metathesis of 1‐octene after 
420 min and at optimum reaction temperatures. 
Temp 
Catalyst  1‐Octene 2  PMPs 2  IPs 2  SMPs 2  S 3  KIn 4  TON 5  TOF 6 
(°C) 
2  35 7  58.5  40.8  0.4  0.3  98  0.12 × 10−4  4136  16.4 × 10−2 
3  60 7  14.8  81.6  0.0  3.6  96  1.89 × 10−4  8881  35.2 × 10−2 
4  80  28.8  68.0  0.3  2.9  96  9.60 × 10−3  6120  24.3 × 10−2 
13  80  65.5  34.0  0.2  1.3  96  5.32 × 10−3  3063  12.2 × 10−2 
14  100  21.2  76.0  0.3  2.5  97  13.54 × 10−3  6825  27.1 × 10−2 
15  100  30.2  67.0  0.3  2.5  96  11.57 × 10−3  6005  23.8 × 10−2 
15  110  4.2  91.0  0.3  4.5  95  17.12 × 10−3  8160  32.4 × 10−2