Synthesis and Reactivity of an Aminocarbene Osmium Complex Formed by Double C-H Activation of a NCH3 Unit

The reaction of [OsCl2(PPh3)(3)] (1) with iPr(2)PCH(2)CH(2)NMe(2) in 2-propanol under reflux affords the Fischer-type aminocarbene complex cis,cis-[OsCl2{kappa(2)(C,P)-CHN(CH3)CH2CH2-PiPr(2)}{kappa(2)(P,N)-iPr(2)PCH(2)CH(2)NMe(2)}] (2) by double C-H activation of one NCH3 group. While treatment of 2 with phenylacetylene leads to the vinylidene complex cis,trans[OsCl2(C=CHPh){kappa(2)(C,P)-CHN(CH3)CH(2)CH(2)PiPr(2)}{kappa(P)-iPr(2)-PCH2CH2NMe2}] (3) by partial opening of the P,N-chelate bond, the reaction of 2 with CO and CNtBu gives rise to ionic compounds of type [OsCl(L){kappa(2)(C,P)-CHN(CH3)CH2CH2-PiPr(2)}{kappa(2)(P,N)-iPr(2)PCH(2)CH(2)OMe}]Cl (4: L = CO, 5: L = CNtBu) by substitution of one chloro ligand. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)