Isatogens. Part VI. Synthesis of isatogens via tolan (diphenylacetylene) intermediates

Abstract

A number of substituted 2-nitrotolans and isatogens have been prepared in high yield from copper(I) 2-nitrophenylacetylide and substituted aromatic iodo-compounds. The reaction has been shown to be affected by both electronic and steric factors and its limitations are discussed. 2-Carbamoyltolans have been shown to cyclise to aminoindenones. A number of novel compounds have been isolated from these reactions and their significance, with regard to the mechanism of the reaction between isatogens and substituted acetylenes, is discussed. The influence of different solvents on the course of the latter reaction is reported.