Selective [2+1+1] Fragmentation of P 4 by heteroleptic Metallasilylenes.

Small-molecule activation by low-valent main-group element compounds is of general interest. We here report the synthesis and characterization ( 1 H, 13 C, 29 Si NMR, IR, sc-XRD) of heteroleptic metallasilylenes L 1 (Cl)MSiL 2 (M=Al 1, Ga 2, L 1 =HC[C(Me)NDipp] 2 , Dipp=2,6- i Pr 2 C 6 H 3 ; L 2 =PhC(N t Bu) 2 ). Their electronic nature was analyzed by quantum chemical computations, while their promising potential in small-molecule activation was demonstrated in reactions with P 4 , which occurred with unprecedented [2+1+1] fragmentation of the P 4 tetrahedron and formation of L 1 (Cl)MPSi(L 2 )PPSi(L 2 )PM(Cl)L 1 (M=Al 3, Ga 4).