Ring-closing metathesis for the synthesis of a molecular gyrotop.

Macrocage molecules with a bridged phenylene rotor have been synthesized as molecular gyrotops, whose cages were constructed by ring-closing metathesis (RCM) of bis(trialkenylsilyl)benzenes. An analysis of the yields of the products in the RCM reaction under various temperature conditions revealed that the desired cage, i.e., a molecular gyrotop, was produced in good yield under reflux, indicating that the cage is a thermodynamically controlled product.