Pt0 and Pd0 olefin complexes of the metalloid N-heterocyclic carbene analogues [EI(ddp)] (ddp=2-{(2,6-diisopropylphenyl)amino}-4-{(2,6-diisopropylphenyl)imino}-2-pentene; E = Al, Ga):: Ligand substitution, H-H and Si-H bond activation, and cluster formation

Various products of the reaction of [E(ddp)] (ddp=2-{(2,6-diisopropylphenyl)amino}-4-{(2,6-diisopro-pylphenyl)imino}-2-pentene; E=Al, Ga) with Pt-0 and Pd-0 olefin complexes are reported. Thus, the reaction of [Pt-(cod)(2)] (cod=1,5-cyclooctadiene) with two equivalents of [Ga(ddp)] yields [Pt(1,3-cod){Ga(ddp)}(2)] (1), whereas treatment of [Pd-2(dvds)(3)] (dvds=1,1,3,3-tetramethyl1,3-divinyldisilox-ane) with [E(ddp)] leads to the monomeric compounds [(dvds)Pd{E(ddp)}] (E=Ga (2a), Al (2b)) by substitution of the bridging dvds ligand. Both 1 and 2a readily react with strong pi-acceptor ligands such as CO or tBuNC to give the dimeric compounds [M{mu(2)-Ga(ddp)}(L)] (L=CO, tBuNC; M=Pt (3a, 5a), Pd (3b, 5b)), respectively. Based on H-1 NMR spectroscopic data, [Pt{Ga(ddp)}(2)(CO)] is likely to be an intermediate in the formation of 3a. Furthermore, reactions of 1 with H, and HSiEt3 yield the monomeric compounds [Pt{Ga(ddp)](2)(H)(2)] (7) and [Pt{Ga(ddp)}(2)(H)(SiEt3)] (8). Finally, the reaction of [Pt(cod)(2)] with one equivalent of [Ga(ddp)] in the presence of H-2 in hexane gives the new dimeric cluster [Pt{mu(2)-Ga(ddp)}(H)(2)](2) (9).