Synthesis and structure of OS(eta(2)-3,3-diphenylcyclopropene)Cl(NO)(PPh3)(2) and the ring-opening reactions of the pi-bound cyclopropene with acids

摘要

Reaction between the zerovalent nitrosyl complex, OsCl(NO)(PPh3)(3) and 3,3-diphenylcyclopropene yields the robust Tr-adduct, Os(eta(2)-3.3-diphenylcyclopropene)Cl(NO)(PPh3)(2) (1), the crystal structure of which reveals the chloride and nitrosyl ligands located mutually trans and the Os, the two PPh3 ligands and the double bond of the cyclopropene, all lying in one plane. Treatment of I with the acids HX (X = Cl, O2CCF3) brings about a ring-opening of the cyclopropene ring (perhaps via an intermediate diphenylvinyl carbene complex) with the organic moiety remaining bound to osmium and with ultimate formation of the cy-diphenylallyl complexes, Os(CH2CH=CPh2)Cl-2(NO)(PPh3)(2) (2) and Os(CH2CH=CPh2)Cl(O2CCF3)(NO)(PPh3)(2) (3), respectively. A crystal structure determination for 2 has been obtained. (c) 2006 Elsevier B.V. All rights reserved.