Steric factors in the azidolysis–thermolysis of some 5-tosyloxymethylbi-cyclo[2.2.2]oct-2-enes to yield 4-azatetracyclo[4.4.0.0.0]decanes

Abstract

Azidolysis of C-19 diastereoisomer tosylesters of morphine derivatives possessing a bridged ring C has been studied and 4-azatetracyclo[4.4.0^2,4.0^3,8]decanes 6b, 6d and 6f were formed via the substitution and subsequent intramolecular cyclization of the (R)-C-19 tosylesters 4b, 4d and 4f, and primarily the ethylidene derivatives 7a, 7b and 7c were obtained from (S)-C-19 tosylesters 4c, 4e and 4g. According to our experience the course of the reaction depends on the configuration of the C-19 centre of chirality and on the spatial requirement of the substitutent on C-6