Abstract:

The thermolysis of (2-methoxyphenyl)methyltitanocene (2) in the presence of various unsaturated substrates regioselectively to yield metallacycles, presumably via the intermediacy of the titanocene-benzyne complex 3, is described. If the thermolysis is effected in the presence of trimethylphosphine, the titanocene-benzyne complex Cp2Ti(eta2-C6H4-2-OMe)(PMe3) (1a) can be isolated. The reactions of 1a and 3 are compared to those of the analogous zirconium complexes.