Modern Synthetic Methods 1986: Conference Papers of the International Seminar on Modern Synthetic Methods 1986, Interlaken, April 17th/18th 1986

363 Pages·1986·6.44 MB·English

by  Kenneth S. Suslick

MODERN SYNTHETIC METHODS
Volume 4 . 1986
Editor:
Prof. Dr. Rolf Scheffold
Institut fur organische Chemie
at
der Un ivers it Bern
FreiestraBe 3
CH-3012 Bern
MODERN SYNTHETIC METHODS
Editor: R. Scheffold
Volume 1 . 1976
M. Makosza, Naked Anions-Phase Transfer
A. Patchornik, Polymer Supported Reagents
D. Seebach, S- and Se-Reagents
1976 Verlag Sauerlander, Otto Salle, Aarau und Frankfurt am Main
Volume 2 . 1980
L. Eberson, Electro-Organic Synthesis
Chiral Building Blocks in Enantiomer Synthesis:
D. Seebach - ex Tartaric Acid
A. Vasella - ex Sugars
A. Fischli - Using Enzymatic Transformations
1980 Verlag Sauerlander, Otto Salle, Aarau und Frankfurt am Main
Volume 3 . 1983
Transition Metals in Organic Synthesis:
J. K. Stille, Principles and Rules
L. S. Hegedus, Group VIII Transition Metals
J.F. Normant, Copper and Manganese
D. Seebach, Titanium and Zirconium
R. Scheffold, B12 and Related Cobalt Complexes
1983 Verlag Sauerlander, Otto Salle, Aarau und Frankfurt am Main
Coedition by John Wiley & Sons, Inc., Chichester
MODERN
SYNTHETIC
METHODS
1986
SOUND AND LIGHT IN SYNTHESIS
K. S. Suslick, Ultrasound in Synthesis
K. Schaffner, Photochemically Generated Building Blocks
M. Demuth, Natural Product Synthesis by
Photochemical Methods
SYNTHESIS OF ENANTIOMERICALLY PURE
COMPOUNDS WITH C,C BOND FORMATION
D. Seebach -via Acetals and Enamines
G. Helmchen -by Asymmetric Diels-Alder Reactions
H. C. Brown -via Chiral Organoboranes
Conference Papers of the International Seminar
on Modern Synthetic Methods 1986
Interlaken, April 17thl18th 1986
Chairman: R. Scheffold
Sponsored and Organized by
The Association of Swiss Chemists
Springer-Verlag
Berlin Heidelberg New York Tokyo
Prof. Dr. Rolf Scheffold
Institut fUr organische Chemie der
Universitat Bern, FreiestraBe 3
CH-3012 Bern
Copyright © Cover Design by Verlag Sauerlander, Aarau/Schweiz
ISBN-13: 978-3-540-16526-2 e-ISBN-13: 978-3-642-82805-8
001: 10.1007/978-3-642-82805-8
Library of Congress Cataloging-in-Publication Data. International Seminar on Modern
Synthetic Methods 1986 (1986 : Interlaken, Switzerland) Sound and light in synthesis. (Modern
synthetic methods ; v. 4) 1. Chemistry, Organic-Synthesis-Congresses. 2. Ultrasonics
Congresses. 3. Photochemistry-Congresses. 1. Scheffold, Rolf. II. Schweizerischer Chemiker
Verband. III. Title. IV. Series. QD262.I567 1986 541.3'9 86-6436
This work is subject to copyright. All rights are reserved, whether the whole or part ofthe
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© by Springer-Verlag Berlin Heidelberg 1986
Softcover reprint of the hardcover 1 st edition 1986
The use of registered names, trademarks, etc. in this publication does not imply, even in the
absence of a specific statement, that such names are exempt from the relevant protective laws
and regulations and therefore free for general use.
The publisher cannot assume any legal responsibility for given data, especially as far as
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chemicals and laboratory equipment.
2152/3140-543210
Dedicated to
Vladimir Prelog
Nobel Laureate
Pre f ace
This paperback is the conference documentat10n of the forth Seminar on
MODERN SYNTHETIC METHODS. It is the aim of these triennial Interlaken
Sem1nars to provide a proper, concise and "ready for use" access to 1mportant
and rapidly developing areas of synthet1c organ1c chem1stry.
The two main themes of the 1986-Seminar are "Sound and Light in Synthesis"
and "Synthesis of Enantiomerically Pure Compounds by C,C Bond Format10n".
The first topic concerns the application of ultrasound in synthesis as well
as the photochemical generation of build1ng blocks and their transformations
into natural products. The second topic reflects the enormous progress in
experience and understanding of organic chemistry directed towards the
synthesis of enantiomerically pure compounds.
This paperback is the compilation of the contributions prov1ded by the six
lecturers, each a leading expert in his f1eld. The reV1ews are praxis
oriented, they descr1be the basic concepts, the1r application 1n organic
synthes1s and conta1n as an integral part representative exper1mental
procedures.
It 1S hoped that th1S book will serve as a gU1de for chem1sts interested
in the art of modern organic synthes1s.
Bern, 31. Januar 1986 Ro If Scheffo 1d
Contents
SOUND AND LIGHT IN SYNTHESIS
Ultrasound in Synthesis .............................................. .
Kenneth S. Suslick
School of Chemical Sciences, University of Illinois at Urbana-Champaign
505 S. Mathews Av. Urbana, Illinois 61801, U. S. A.
Photochemically Generated Building Blocks I
The Tricyclooctanone Approach to Polyquinane Synthesis (Part I)
The Underlying Photochemistry ........................................ 61
Kurt Schaffner and Martin Demuth
Max-Planck-Institut fur Strahlenchemie
Stiftstrasse 34 - 36, D-4330 Mulheim a. d. Ruhr
Photochemically Generated Building Blocks II
The Tricyclooctanone Approach (Part II). Photochemical Methods in
Cyclopentanoid Natural Products Synthesis - A Comparison ............ 89
Martin Demuth
Max-Planck-Institut fur Strahlenchemie
Stiftstrasse 34 - 36, D-4330 Mulheim a. d. Ruhr
SYNTHESIS OF ENANTIOMERICALL Y PURE COMPUNDS
WITH C,C BOND FORMATION
EPC Syntheses with C, C Bond Formation via Acetals and Enamines ..... 125
Dieter Seebach, Rene 1mwinkelried and Theodor Weber
Laboratorium fur Organische Chemie der ETH-Zurich,
Universitatsstrasse 16, CH-8092 Zurich.
Asymmetric Diels-Alder Reactions with Chiral Enoates as Dienophiles 261
Gunter Helmchen, R. Karge and J. Weetman
Organisch-Chemisches 1nstitut der Universitat Heidelberg,
1m Neuenheimer Feld 270. D-6900 Heidelberg.
Enantiomerically Pure Compounds via Chiral Organoboranes ............ 307
Herbert C. Brown, Prabhakar K. Jadhav and Bakthan Singram
Department of Chemistry, Purdue University,
West Lafayette, Indiana 47907, U. S. A.
ULTRASOUND IN SYNTHESIS
Kenneth S. Suslick
School of Chemical Sciences
University of Illinois at Urbana-Champaign
505 S. Mathews A v.
Urbana, Illinois 61801
U.S.A.
1. Introduction and Intent....................................... 2
2. Origins of the Chemical Effects of Ultrasound................. 3
2.1. The Nature of Acoustic Cavitation...................... 3
2.2. Cavitation in Homogeneous Media........................ 4
2.3. Cavitation at Surfaces................................. 9
3. Experimental Influences on Sonochemistry...................... 12
3.1. Reactor Design and Configuration....................... 12
3.2. Extrinsic Variables .. ......... ...................•.... 16
4. Synthetic Applications of Ultrasound.......................... 20
4.1. Homogeneous Systems.................................... 20
4.1.1. Aqueous Sonochemistry........................... 20
4.1.2. Non-Aqueous Sonochemistry....................... 23
4.1.2.1. Neat Liquids......... .•••.•. ..••.•.... ..• 23
4.1.2.2. Stoichiometric Reactions................. 23
4.1.2.3. Initiation of Homogeneous Catalysis...... 29
4.2. Heterogeneous Sys terns. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4.2.1. Liquid-Liquid Reactions......................... 30
4.2.2. Liquid-Solid Reactions.......................... 32
4.2.2.1. Non-Organometallic Reagents.............. 32
4.2.2.2. Reactive Metals (dO, d10)................ 36
4.2.2.3. Transition Metals..... ..•..• ••••... .•. ••• 41
4.2.3. Applications to Heterogeneous Catalysis......... 45
5. Concluding Remarks............................................ 46
6. Representative Experimental Procedures........................ 47
7. Acknowledgments. • . • • • • . • • • . • . • . . • . • . . . . . • • • • • • • . . . . . . • • • . • . . .• 50
8. References.................................................... 51
Modern SynthelIc Methods 1986, Vol 4
EdItor R Scheffold
© Spnnger-Verlag Berhn HeIdelberg 1986
2
1. INTRODUCTION AND INTENT
The chemicall and blologica12 effects of ultrasound were flrst reported by
Loomis more than 50 years ago. In spi te of early work in the area of
sonochemistry, interest wi thin the chemlcal community remained exceedingly
modest until the past few years. With the advent of inexpensive and reliable
sources of ultrasound, however, increasing use of sonochemistry ln a variety of
reactions is being reported. The purpose of this reVlew is to act as a
cri tical lntroduction for those interested ln the chemical effects of
ul trasound and the synthetic appl ications of sonochemistry. In addition, a
brief overview of the physics of acoustic cavitation is presented in order to
explain the origin of sonochemical reactivity. Interested readers are referred
to earlier reviews of general sonochemical Phenomena.3,4,5
Some of the terminology ln this area will be unfamiliar to most chemists.
Cavitation is the formatlon of gas bubbles (or cavities) in a liquid and occurs
when the pressure wi thin the liquid drops sufficiently lower than the vapor
pressure of the liquid. Cavi tation can occur from a vari ety of causes:
turbulent flow, laser heating, electrical discharge, boiling, radiolysis, or
acoustic irradlation. We will be concerned exclusively with acoustic
cavi tat ion • When sound passes through a liquid, it consists of expansion
(nega t i ve-pressure) waves and compression (positi ve-pressure) waves. These
cause vapor and gas-fllled bubbles to grow and recompress. Acoustic cavitation
can lead, as dlscussed later, to an implosive collapse of such cavities wi th
associated high-energy chemistry. The importance of acoustic cavitation
extends well beyond its chemical effects, and is relevant to studies of heat
transport, liquid tensile strengths, and superheating and boiling phenomena.6,7
Furthermore, since ul trasound is heav ily used both for med i cal trea tment
(hyperthermia for soft tissue traumas) and diagnosis (sonography of fetal
development), the biological and chemical effects of ultrasound are of
immediate import.a. nce to the health services community.8,9,lO We will use the
symbol, -)-)-) in this review to indicate ultrasonic irradiation or
"sonication" of a solution leadlng to a sonochemical reaction. Sonocatalysis
will be restricted in its use only to the creation of a catalytically competent
intermediate by ultrasonic irradiation; we will not refer to a simple
sonochemical rate enhancement of an already ongoing reaction by this term.