An η2transition state for the insertion of M(PR3)2fragments (M = Pd or Pt) into the phosphorus–carbon bonds of pentacarbonyl(phosphirane)tungsten complexes

Abstract
The reaction of (E)- and (Z)-[W(CO)5( [graphic omitted]HPh)] complexes with [M(PR3)2(C2H4)][M = Pd, (PR3)2= dppe (Ph2PCH2CH2PPh2); M = Pt, PR3= PPh3] has been studied and the following products [which result from insertion of the M(PR3)2 frogment into the phosphirane ring] have been fully characterised by NMR spectroscopy: (2R*,3S*,4S*)-(±)-, (2R*,3S*,4R*)-(±)- and (2R*,3S*,4R*)-(±)-[(dppe) Pd(CHPhCHPhPPh)W(CO)5]; (2S*,3S*,4S*)-(±)-, (2S*3R*4R*)-(±)- and (2S*,3S*,4R*)-(±)-[(Ph3P)2Pt(CHPhCHPhPPh)W(CO)5]; and trans-(2S*,3S*,4R*)-(±)-[(Ph3P)(OC)Pt-(CHPhCHPhPPh)W(CO)5]. The crystal and molecular structures of (Z)-[W(CO)5([graphic omitted]HPh)], (2R*,3S*,4R*)-(±)- and (R*,3S*,4S*)-(±)-[(dppe)Pd(CHPhCHPhPPh)W(CO)5] have been determined. The configurations of the products are interpreted in terms of a transition state in which a P–C bond is η2-co-ordinated to M(PR3)2 fragment.