Chapter 54 - Compounds with seven-membered and larger heterocyclic rings containing one or more of unusual hetero elements together with nitrogen or elements of group VI

Abstract

This chapter reviews the literature available from 1995 to 1997. An excellent series of reviews is published in Comprehensive Heterocyclic Chemistry II.. The heterometallic aluminum, boron, gallium, and indium compounds have been surveyed, and this includes reference to some cyclic systems of relevance. The use of benzo [2, 4, 3] dioxaborepin as a new boronic acid protecting group which undergoes deprotection under mild conditions is reported. The compounds containing oxygen and/or sulphur as the additional elements are presented with structure diagrams. The new dibenzophosphaselenocine heterocycles is synthesized by the reaction of the bis (2-bromomethylphenyl) phenylphosphine oxide with sodium selenide is explained under compounds containing other Group VI elements.