Homo‐ and Heteronuclear Complexes of (Pentamethylcyclopentadienyl)rhodium( III ) Bearing Bis(diphenylphosphanylmethyl)phenylphosphane

Reaction of [Cp*RhCl 2 ] 2 ( 1 ) with bis(diphenylphosphanylmethyl)phenylphosphane (dpmp) in the presence of KPF 6 generated the mono‐ or bi‐nuclear complexes [(Cp*RhCl)(dpmp‐ P,P,P )(RhCl 2 Cp*)](PF 6 ) ( 2 ) or [Cp*RhCl(dpmp‐ P,P )](PF 6 ) ( 3 ), depending on the reaction conditions. These complexes have two chiral centers at Rh and the central P atoms, and the diastereomers were separated by successive recrystallization. The structures of 2(B) with an R Rh S P / S Rh R P pair and 3(A) with an R Rh S P / S Rh R P pair were elucidated by X‐ray analyses. Reaction of 1 with an excess of dpmp in the presence of Ag(OTf) generated a hetero‐tetranuclear complex [{Cp*RhCl 2 (dpmp‐ P,P,P )Ag} 2 ](OTf) 2 ( 4 ). An X‐ray analysis revealed that each Cp*RhCl 2 moiety is connected by a terminal P 1 atom of the dpmp ligand and each Ag atom is two‐coordinate and is surrounded by another terminal P 3 atom, and a central P* 2 atom of the other dpmp ligand. A mixture of 1 and dpmp was treated with Au(SC 4 H 8 ) or CuCl in the presence of KPF 6 , generating the hetero‐tetranuclear complexes [{Cp*RhCl 2 (dpmp‐ P,P,P )M} 2 ](PF 6 ) 2 ( 7 : M = Au; 8 : M = Cu), in which the structures, except for the Cl‐bridged structure of 8 , are fundamentally similar to that of 4 . These complexes were also prepared by the reactions of 3 with Au(SC 4 H 8 ) or CuCl. Complex 3 reacted with AgOTf to afford [Cp*Rh(dpmp‐ P,P,P )](OTf) 2 ( 5 ). Treatment of 3(A) (a diastereomer with an R Rh S P2 / S Rh R P2 pair) with 1 , [( p ‐cymene)RuCl 2 ] 2 or PdCl 2 (cod) gave [Cp*RhCl(dpmp‐ P,P,P )RhCl 2 Cp*](PF 6 ) ( 2 ) or [Cp*RhCl(dpmp‐ P,P,P )RuCl 2 ( p ‐cymene)](PF 6 ) ( 6 ), respectively. These addition reactions proceeded stereoselectively. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)