Heavy Group 13 Elements (Ga, In) in Frustrated Lewis Pair Reactions and Hydrogenation Catalysi

The Lewis acids Ga(C6F5)3 and In(C6F5)3 were synthesized and their Lewis acidities have been investigated by experimental and computational methods. In the presence of phosphine donors, these frustrated Lewis pairs (FLPs) were shown to heterolytically split dihydrogen and catalyze the hydrogenation of N-tert-butylbenzimine. Furthermore, the reactions with diphenyl disulfide produce phosphonium-gallates or phosphonium-indates of the form [ tBu3PSPh][PhSE(C6F5) 3] and [tBu3PSPh][(mu-SPh)(E(C 6F5)3)2] (E=Ga, In), while the reactions with phenylacetylene gave mixtures of the products [tBu3PH][PhCCE(C 6F5)3] and tBu3P(Ph)C=C(H)E(C 6F5)3. A number of these compounds were crystallographically characterized.