Conference paper

A Remarkably Stable and Simple Monocyclic Thiepin. Synthesis and Properties of 2, 7-Di-tert-butyl-4-ethoxycarbonyl-5-methylthiepin

I. Murata ; Department of Chemistry, Faculty of Science, Osaka University, Toyonaka, Osaka 560, Japan
K. Nishino ; Department of Chemistry, Faculty of Science, Osaka University, Toyonaka, Osaka 560, Japan
S. Yano ; Department of Chemistry, Faculty of Science, Osaka University, Toyonaka, Osaka 560, Japan
Y. Kohashi ; Department of Chemistry, Faculty of Science, Osaka University, Toyonaka, Osaka 560, Japan
K. Yamamoto ; Department of Chemistry, Faculty of Science, Osaka University, Toyonaka, Osaka 560, Japan

Abstract

A simple monocyclic 8n electron thiepin, 2,7-di-tert-butyl-4-
-ethoxycarbonyl-5-methylthiepin (13) stabilized by two bulky tert-
-butyl groups at 2- and 7-positions, was synthesized from 2,6-di-
-tert-butyl-4-methylthiopyrylium tetrafluoroborate (11). In spite of
of its monocyclic thiepin structure, the compound 13 showed remarkable
thermal stability and had a half-life of 7.1 h at 130 °C.
Judging from the 1H-NMR spectrum, the thiepin 13 is considered
to be an atropic molecule.
Synthetic details of 11 and 13, and the chemical and physical
properties of 13 are also described.

Keywords

Hrčak ID:

194476

URI

https://hrcak.srce.hr/194476

Publication date:

25.1.1981.

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