Metacyclophane and related compounds. Part 11. Reaction of 8,16-bis(bromomethyl)[2.2]metacyclophane and 8,16-bis(bromomethyl)-5,13-di-t-butyl[2.2]metacyclophane with Grignard reagents

Abstract

Reaction of 8,16-bis(bromomethyl)-(2a) and 8,16-bis(bromomethyl)-5,13-di-t-butyl[2.2]metacyclo-phane (2b) with Grignard reagents (3a–f) afforded the corresponding 8,16-dialkyl derivatives (4a–j) together with the spiro compound (5a) and (5b), respectively.

The yield of (4) was dependent upon the reaction time and the steric bulk and quantity of Grignard reagent used.

Reaction of 8-bromomethyl-16-methyl[2.2]MCP (13c) with Grignard reagents afforded the corresponding 8-alkyl-16-methylMCP (15) together with the reduction product 8,16-dimethyl[2.2] MCP (1a), and the bis[2.2]MCP (16a). However, 8-bromomethyl-16-methyl-5,13-di-t-butyl[2.2]MCP (13d) gave only the corresponding 8-alkyl-16-methyl MCP in good yield.