The Chemistry of Ethynyl, Olefin and Carbene Complexes of Gold and Platinum

[摘要] Gold Ethynyl complexes, [Au(C=CR)L], (L = PPh3, R = H, Me, Et, Ph or CP3; L = P(C6H4Me-p)3, R = Ph) can be readily produced from phosphinegold chlorides and RC=CH in ethanolic sodium ethoxide. When R = H a second reaction will produce the digold species LAuC =CAuL (L = PPh3,P(C6H4Me-p)3 or P(C6H4CMe-p)3. ) In a similar manner the cylopentadienyl complex [Au(C5H5)PPh3 can be conveniently prepared from AuClPPh3 and C5H6, in ethanolic sodium ethoxide. In solution there is rapid exchange of free phosphine with the coordinated phosphine of AuCIL and [Au(C=CPh)L], The phenylethynyl group of [Au(C=CPh)(PPh3)] will exchange quantitatively with chloride of HgCl2 producing AuClPPh3 and Hg(C=CPh)3 . When [Au(C=CPh)L] (L = PPh3,P6H4Me-p)3 ) is allowed to react with cis [ptCl2 (CO)(PMePh2)] (2:1 mole ratio) the product is cis-[pt( C=CPh)2(CO)(EMePh2)3 and AuClPPh3 . If the same reaction is performed with a 1:1 mole ratio the phenylethynyl group transfers quantitatively to produce [ptCl(C=CPh)(CO)(PMePh2)], isomer II (Cl trans to L). When followed by low temperature 31P nmr spectroscopy the first step of the reaction is not stereospecific with an initial mixture of [PtCl(C=CPh)(CO)(pMePh2)] which then reacts further with cis-[PtCl2-(CO)(PMePh.

[发布机构] University:University of Glasgow

[关键词] Organic chemistry