Synthesis 1995; 1995(8): 957-963
DOI: 10.1055/s-1995-4024
paper
© Georg Thieme Verlag, Rüdigerstr. 14, 70469 Stuttgart, Germany. All rights reserved. This journal, including all individual contributions and illustrations published therein, is legally protected by copyright for the duration of the copyright period. Any use, exploitation or commercialization outside the narrow limits set by copyright legislation, without the publisher's consent, is illegal and liable to criminal prosecution. This applies in particular to photostat reproduction, copying, cyclostyling, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.

Conjugate Addition Reactions of Functionalized Organozinc and Copper Reagents to (2-Propynylidene)morpholinium Triflates

Martina Brunner, Gerhard Maas*
  • *Fachbereich Chemie, Universität Kaiserslautern, Erwin-Schrödinger-Strasse, D-67663 Kaiserslautern, Germany, Fax +49(731)5022803
Further Information

Publication History

Publication Date:
31 December 2000 (online)

Organozinc and copper reagents of the type IZnCu(CN)-RC-FG [RC-FG = cyanoalkyl (6a, c), ethoxycarbonylalkyl (6b, d), functionalized aryl (10a-c)] undergo conjugate addition to the (2-propynylidene)morpholinium triflates 1a, b. The expected morpholinoallenes or the tautomeric 1- or 2-morpholino-1,3-dienes cannot be isolated, however. After hydrolytic workup, α,β-unsaturated ketones 7 or 12 are usually obtained. In some cases, 2-acylcyclopent-2-en-1-ones 8 or 2-acylindenones 13 are found, which result from cyclization of the initially formed morpholinoallenes. The 2-morpholino-1,3-dienes 17 can be intercepted in a [4+2] cycloaddition with electron-deficient alkenes, and the cyclohexanones 19 are obtained after hydrolytic workup.

    >