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 (H-1, C-13, Si-29 NMR, IR, sc-XRD) of heteroleptic metallasilylenes L-1(Cl)MSiL2 (M=Al 1, Ga 2, L-1=HC[C(Me)NDipp](2), Dipp=2,6-(Pr2C6H3)-Pr-i; L-2=PhC((NBu)-Bu-t)(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).