Bicyclic 5-5 Systems with One Bridgehead (Ring Junction) Nitrogen Atom: One Extra Heteroatom 1:0

Abstract

This chapter covers those bicyclic 5–5 systems with one ring junction nitrogen atom and one extra heteroatom. There are nine possible parent structures that are presented in this chapter, in which the double bonds can be arranged in different ways to give 22 basic structures. Reduced derivatives of all these parent structures that are, dihydro, tetrahydro, and fully saturated systems increase greatly the number of possible compounds. Oxo compounds are also possible, and each of the nine parent structures has five different positions where the carbonyl group could be located. There is a related chapter in the second edition of Comprehensive Heterocyclic Chemistry (CHEC-II) untitled ‘Bicyclic 5–5 System with One Ring Junction Nitrogen Atom: one Extra Heteroatom 1:0’, that cover the knowledge on this type of compounds from 1982 to 1995 . No general review unless this one, exists, nor are there systematic studies on the subject.