Download PDF
Synthesis 2001(7): 1076-1080
DOI: 10.1055/s-2001-14559
PAPER
© Georg Thieme Verlag Stuttgart · New York

Cyclobutenone Ethylenedithioacetals and Their Ready Electrocyclic Ring Opening

Wilko Regenhardta, Ernst Schaumann*a, Harold W. Moore*b
a Institut für Organische Chemie, Technische Universität Clausthal, Leibnizstraße 6, 38678 Clausthal-Zellerfeld, Germany
Fax: +49(5323)722858; e-Mail: ernst.schaumann@tu-clausthal.de;
b Department of Chemistry, University of California-Irvine, Irvine, CA 92697-2025, USA
Fax: +1(949)8242210; e-Mail: halmoore@uci.edu;
Further Information

Publication History

Received 5 February 2001
Publication Date:
30 September 2004 (online)

    Permissions and Reprints All articles of this category

Abstract

Reported here is a general regiospecific synthesis of cyclobutenedione monoethylendithioacetals which readily undergo ring opening after addition of an organolithium reagent. The generated acyclic enols either tautomerize to the corresponding carbonyl compounds or can be trapped as silylenol ethers, which serve as electron rich dienes in Diels-Alder additions with tetracyanoethylene or maleic anhydride.

Key words

cyclobutenones - dithioacetals - transthioacetalization - electrocyclic ring opening - Diels-Alder reaction