Selective [2+1+1] Fragmentation of P4 by heteroleptic Metallasilylenes

Small‐molecule activation by low‐valent main‐group element compounds is of general interest. We here report the synthesis and characterization (1H, 13C, 29Si NMR, IR, sc‐XRD) of heteroleptic metallasilylenes L1(Cl)MSiL2 (M=Al 1, Ga 2, L1=HC[C(Me)NDipp]2, Dipp=2,6‐iPr2C6H3; L2=PhC(NtBu)2). Their electronic nature was analyzed by quantum chemical computations, while their promising potential in small‐molecule activation was demonstrated in reactions with P4, which occurred with unprecedented [2+1+1] fragmentation of the P4 tetrahedron and formation of L1(Cl)MPSi(L2)PPSi(L2)PM(Cl)L1 (M=Al 3, Ga 4). Si cuts in: Heteroleptic metallasilylenes L1(Cl)MSiL2 (M=Al 1, Ga 2) react selectively with white phosphorus in a [2+1+1] fragmentation of the P4 tetrahedron to give L1(Cl)MPSi(L2)PPSi(L2)PM(Cl)L1 (M=Al 3, Ga 4).