MIGRATORY-INSERTION REACTIONS OF OSMIUM(II) ETHYL COMPLEXES DERIVED FROM AN OSMIUM(0) ETHYLENE COMPLEX

Article abstract of DOI:10.1016/S0022-328X(00)85765-4

Reaction between Os(CO)2(PPh3)3 and C2H4 gives Os(η²-C2H4)(CO)2(PPh3)2.A series of osmium(II) ethyl complexes, OsEtX(CO)2(PPh3)2 (X=Cl, I, O2CCF3, OClO3) results from reaction of Os(η²-C2H4)(CO)2(PPh3)2 with one equivalent of the appropriate acid.In the presence of excess HCl a migratory-insertion reaction ensues and the resulting propionyl ligand is protonated on oxygen to give an hydroxy-carbene complex OsCl2(CO)(PPh3)2.Migration of the ethyl group in OsEt(OClO3)(CO)2(PPh3)2 is induced by addition of CO, CNR or the potentially bidentate ligand S2CNEt2^- giving (CO)3(PPh3)2>ClO4, (CO)(CNR)2(PPh3)2>ClO4 and Os(S2CNEt2)(CO)(PPh3)2, respectively.