The Journal of Organic Chemistry

Medium-Ring Systems. 6.1 Synthesis and Isomerizations of Medium-Ring 3-Methylenecycloalkanones and 3-Methylcycloalkenones

P Eskola, JA Hirsch

Index: Eskola, Philip; Hirsch, Jerry A. Journal of Organic Chemistry, 1997 , vol. 62, # 17 p. 5732 - 5742

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Citation Number: 5

Abstract

A series of 3-methylenecycloalkanones with ring sizes 7-10 has been prepared and subjected to base-catalyzed isomerization. Equilibrium between these exocyclic isomers and the corresponding 3-methyl-2-cycloalkenones and 3-methyl-3-cycloalkenones was reached in the 7-and 8-membered rings. The presence of the β-methyl shifts these equilibria toward the Δ2 isomer in each ring relative to the unsubstituted compounds and to ...