Bisphosphine silver complex

Simple chiral bisphosphine silver(I) complexes have been reported by Yamamoto to catalyze enantioselective addition reactions of trimethoxysilyl enolates [149, 150] and diketenes [150] to aldehydes. The aldol addition reaction with diketene 301 in Equation 28 is illustrative [150]. The requisite tin enolates are generated in situ from the corresponding enol acetates or diketenes upon exposure to Me3SnOMe or Bu2Sn(OMe)2. This represents a noteworthy example of a transition-metal-catalyzed process involving aldol addition that can be carried out successfully in a polar, protic solvent (methanol). 

In 2000 Xumu Zhang and co-workers reported a bisphosphine complex of rhodium, [RhCl(dppb)]2, which, when used with silver hexafluoroantimonate, in some cases offers a rate advantage over the Wilkinson s catalyst/silver triflate system [28], allowing the reaction to be conducted at room temperature (Tab. 13.5). Scott Gilbertson and coworkers reported a related example, employing [Rh(dppe)(CH2Cl2)2] SbFg as a catalyst for the [5+2] reaction (Tab. 13.5, entry 5) [29]. 

Hayashi and Ito have shown that the reaction of methyl isocyanoacetate (MeOCOCH2NC) with aldehydes is catalyzed by gold [339, 408, 752, 1060] or silver [951] complexes. In the presence of ferrocenyl bisphosphines 3.41 (R = CH2CH2NMe2 or CH2CH2N(CH2)5) the reaction is diastereo- and enantio-selective, and provides trans oxazolines 6.131. These oxazolines are precursors of... 

The rhodium-phosphine catalyst [Rh(T)-L] was prepared from [ RhCl(NBD) 2] and the chelating bisphosphines 141 and 142 [59] following chloride removal with silver triflate. In fact, the two systems on Scheme 3.52 and 3.53 could be mn together, with the net result of hydrogenation of ketones by molecular hydrogen. The same rhodium-phosphine complex catalyzed the direct hydrogenation of flavin mononucleotide to dihydroflavin mononucleotide [59],... 

A series of homoleptic copper(i), silver(i), and gold(i) complexes of two bisphosphine ligands l,2-bis(diphenylphosphino)benzene, dppb bis[2-(diphenylphosphino)phenyl]ether, POP has been studied to demonstrate that these species are very low emissive in solution but highly luminescent in the solid state. In particular, the silver and copper complexes afford quite broad electroluminescence spectra with white light emission when used in the fabrication of light-emitting devices. ... 

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