Preparation and structures of novel [2.2.2]metacyclophane tweezers
Abstract
[2.2.2]Metacyclophane (MCP) tweezers 7 and azo[2.2.2]MCP tweezers 8 were prepared from 21-nitro[2.2.2]MCP 2, which was obtained by the ipso-nitration of [2.2.2]MCP 1. X-Ray crystal structural analysis shows the MCP tweezers 7 to have the anti-conformation. The photothermal isomerization of azo[2.2.2]MCP tweezers 8 was studied by ‡ = 71 ± 7 kJ mol−1. The complexation constant of 8 with