3,3-Dichloroprop-2-ene Iminium Salts (Vinylogous Viehe Salts): A Study of Their Reactivity Towards Nucleophiles

Ullrich Jahn; Jens Andersch; Werner Schroth

doi:10.1055/s-1997-1221

Synthesis 1997; 1997(5): 573-588
DOI: 10.1055/s-1997-1221

feature article

© 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.

3,3-Dichloroprop-2-ene Iminium Salts (Vinylogous Viehe Salts): A Study of Their Reactivity Towards Nucleophiles

Ullrich Jahn, Jens Andersch, Werner Schroth^*

^*Institut für Organische Chemie der Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Straße 2, D-06099 Halle (Saale), Germany, Fax +49(345)5527030

Abstract

PDF Download All articles of this category

The title compounds 3 react regioselectively at either the 1- or 3-position depending on the reaction partner. Chloro substitution affording new propene iminium salts is preferred e.g. in the reaction with mercaptans (to 10, 11), amines (to 7, 14, 15), and some activated arenes and hetarenes (to 26, 27). Nucleophilic attack at the 1-position providing an allyl or allylidene structure is observed e.g. in the reaction with water (to 4), alcohol (to 6), trialkyl phosphite (to 21, 22), trimethylsilyl cyanide (to 30), Grignard reagents (to 31), and acceptor activated methylene compounds (to 33-44). Reaction at both positions with heterocyclization to 13 occurs with thioamide functions. The regiochemistry depends on a complex interplay of several factors in contrast to the FMO predicted orientation. The utility of 3 and some consecutive products as versatile C₃-building blocks for further syntheses is foreseeable.

iminium salts - ambident reactivity - regioselectivity - nucleophilic addition/substitution - C₃-building blocks

PDF (1774 kb)