Synthesis 2015; 47(22): 3593-3610
DOI: 10.1055/s-0034-1378805
paper
© Georg Thieme Verlag Stuttgart · New York

Further Developments in the Reaction of 2-Aza-1,3,5-trienes with Superbases: Competitive Formation of New 4,5-Dihydro-1,3-thiazoles, Dihydroazepines, and Azepines by Tandem Deprotonation–Cyclization

Nina A. Nedolya*
A. E. Favorsky Irkutsk Institute of Chemistry of the Russian Academy of Sciences, Siberian Branch, Favorsky Street 1, 664033 Irkutsk, Russian Federation   Email: nina@irioch.irk.ru
,
Olga A. Tarasova
A. E. Favorsky Irkutsk Institute of Chemistry of the Russian Academy of Sciences, Siberian Branch, Favorsky Street 1, 664033 Irkutsk, Russian Federation   Email: nina@irioch.irk.ru
,
Alexander I. Albanov
A. E. Favorsky Irkutsk Institute of Chemistry of the Russian Academy of Sciences, Siberian Branch, Favorsky Street 1, 664033 Irkutsk, Russian Federation   Email: nina@irioch.irk.ru
,
Boris A. Trofimov
A. E. Favorsky Irkutsk Institute of Chemistry of the Russian Academy of Sciences, Siberian Branch, Favorsky Street 1, 664033 Irkutsk, Russian Federation   Email: nina@irioch.irk.ru
› Author Affiliations
Further Information

Publication History

Received: 08 May 2015

Accepted after revision: 05 June 2015

Publication Date:
03 August 2015 (online)


Abstract

Allyl- and benzylsulfanyl-substituted 2-aza-1,3,5-trienes, which are readily available from alkoxyallenes, isothiocyanates, and allyl or benzyl bromide, are easily transformed into polyfunctionalized 4,5-dihydro-1,3-thiazoles (2-thiazolines) through deprotonation of the activated SCH2 group upon treatment with superbase, followed by intramolecular [1,5]-ring-closing. Competitive deprotonation of the methyl group or methylene fragment of the ketimine function of the same molecule, followed by [1,7]-electrocyclization, leads to seven-membered azaheterocycles, dihydroazepines and/or azepines.

Supporting Information