Reactions of Enone Ethylene Ketals with Methyl Diazomalonate/Bis(acetylacetonato)copper(II)


Sezer O. , DAUT A. , ANAC O.

Helvetica Chimica Acta, vol.78, no.8, pp.2036-2041, 1995 (Journal Indexed in SCI Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 78 Issue: 8
  • Publication Date: 1995
  • Doi Number: 10.1002/hlca.19950780811
  • Title of Journal : Helvetica Chimica Acta
  • Page Numbers: pp.2036-2041

Abstract

Several cyclic and acyclic enones and their ethylene ketals/acetals were reacted with dimethyl diazomalonate under bis(acetylacetonato)copper(II) catalysis. Cyclohex‐2‐en‐1‐one (1) yielded only C–H insertion products 2 and 3, whereas but‐3‐en‐2‐one gave a cyclopropane albeit in very low yield. The ethylene ketals 6 of cyclopent‐2‐en‐1‐one and cyclohex‐2‐en‐1‐one gave the corresponding cyclopropanes 7, which were in turn cleaved to the ketones 8. The acetals 9 and 10 of crotonaldehyde ((E)‐but‐2‐enal) and cinnamaldehyde ((E)‐3‐phenylprop‐2‐enal), respectively, yielded C–O insertion and [2,3]‐sigmatropic rearrangement products 11b, c and 12b, c, as well as cyclopropanes 11a and 11b, all of which are polyfunctional and synthetically useful compounds. Copyright © 1995 Verlag GmbH & Co. KGaA, Weinheim