Dppm related complexes preparation

A new, versatile, one-step route to bis(diphenylphosphino)methane (dppm) metal carbonyl complexes involving NaBH4 reduction of a metal salt/dppm mixture under CO has been developed. The reaction outcome is determined by careful control of the conditions. With Co the complexes [Co(Ti -dppm)2(CO)][Co(CO)4], Co2( i-dppm)2(CO)4, Co2(g-dppm)2(g-CO)2(CO)2, and Co2(g-dppm)2(g-H)(g-PPh9)(CO)2 can dl be obtained as the major product. CoBH2(ti-dppm)(Ti -dppm)(CO)2, the first stable metallaborane, is a minor product and other and Ti -dppm-Co-CO complexes can also be prepared. With Ni, Ni( r -dppm)2(CO)2, Ni2(g-dppm)2(g-CO)(CO)2 and [Ni2(g-dppm)2( i-PPh2)(CO)2]X can all be prepared as major products. The heterobinuclear CoRh(g-dppm)2(CO)3 is similarly prepared from Co /Rh °/dppm/BH47CO reactions and related (e.g., Co-Mn, Ni-Cu) complexes can be prepared by two-step processes. Pd gives at least five Pd-dppm-CO complexes. 

S=G(NH2)2 Gp(dppf)][PF6] and [Ru Hrelated complexes [Ru / )-S=GG2H4S2 Gp(dppf)]Gr and [Ru / (A)-S=GG2H2S2 Gp(dppf)]Gr have been prepared directly from [RuGlGp(dppf)] and ethylene or vinylene trithiocarbonate, respectively, the presence of a chloride abstractor not being required in this case. " ... 

Flydrido complexes snch as [OsFl6(PR3)2] (see Hydride Complexes of the Transition Metals) can be prepared by reaction of [0s02Cl2(PR3)2] with LiAlH4, and are related to the Os hydrido complexes [OsFl4(PR3)( -dppm)] and... 

Treatment of the related [Pt2HMe(//-H)(//-dppm)2]+ cation with dppm, PMe2Ph, or PPh3 causes elimination of dihydrogen (but not methane) and formation of [Pt2MeL(/i-dppm)2]+. The complex where L = rjl-dppm has also been prepared by addition of methyl iodide to [Pt2(dppm)3]. The elimination follows second-order kinetics, and in the reaction with PPh3 the intermediate [ H( Ph 3 P)Pt( fi-H)( -dppm)2 PtMe]+ could be observed by NMR spectroscopy at low temperature (115) ... 

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