Carbometalated Complexes Possessing Tripodal Pseudo-C3-Symmetric Triptycene-Based Ligands

New air-stable tripodal triphosphine ligands 1,8,13-tris-(diisopropylphosphino)-2,3-dimethoxytriptycene (P(3)T1) and 1,8,13-tris-(diphenylphosphino)-2,3-dimethoxytriptycene (P(3)T2) are presented and discussed. Their synthesis is based on the first practical synthesis of 1,8,13-tribromotriptycene. Reaction with palladium leads to the formation of new pseudo-C-3-symmetric carbometalated complexes: namely, Pd(P(3)T1)CI and Pd(P(3)T2)CI. The catalytic activity of the new ligands and complexes was tested in the palladium-catalyzed chemoselective transfer hydrogenation of a,beta-unsaturated ketones.