B,y- Unsaturated ketones

Library of Congress Cataloging in Publication Data (Revised) Main entry under title Triplet states. (Topics in current chemistry 54-55, 66) Includes bibliographies and indexes. CONTENTS 1. Devaquet, A. Quantum-mechanical calculations of the potential energy surfaces of triplet states. Ipaktschi, J., Dauben, W. G., and Lodder, G. Photochemistry of B. y-unsaturated ketones. Maki, A. H. and Zuclich, J. A. Protein triplets states, [etc.] 1. Excited state chemistry-Addresses, essays, lectures. 2.Triplet state-Addrcsses, essays, lectures. I. Series Topics in current chemistry 54 fete.] QD1. F 58 vol. 54-55 [QD461.5] 540 8s [54P.24] 75-1466 ISBN 0-387-07107-5 (v. 1)... 

The [1,3] shift may be concerted (69), however, its occurrence from a wide variety of B,y-unsaturated ketones with very different structural requirements for the rearrangement, suggests that a-cleavage occurs from to yield a biradical which can rearrange or undergo recyclization, B-cleavage, and ring expansion. The observed ratio of these paths is structure dependent. 

B,y-Unsaturated ketones have been prepared in moderate yield through the acylation of ir-allyinickel complexes with activated 2-pyridyl caiboxylates. But, isomerization of the initially formed unconjugated alkene resulted in mixtures of products and limited the value of the method. Substituted ir-allylnickel complexes derived from crotyl bromide or cinnamyl bromide were acylated in 79% and 50% yields, respectively, without formation of the a,p-unsaturat ketone. ... 

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