Reactions of (Triphenylphosphine)gold(I) Enolates and Homoenolates

Article abstract of DOI:10.1246/bcsj.61.3649

Some reactions of (triphenylphosphine)gold(I) enolates and homoenolates, which are respectively prepared by the reaction of trimethylsilyl ethers of enols and cyclopropanols with (triphenylphosphine)gold(I) chloride in the presence of cesium fluoride, are described.The aldol reaction of (triphenylphosphine)gold(I) enolates with carbonyl compounds is efficiently promoted by Lewis acids such as titanium tetrachloride and diethylammonium chloride to produce β-hydroxy carbonyl compounds. (Triphenylphosphine)gold(I) enolate reacts with phenyl acetylene to afford (triphenylphospine)gold(I) phenylacetylide in good yield.Reaction of (benzoylmethyl)(triphenylphosphine)gold(I) (3a) with chlorotrimethylsilane produces α-(trimethylsilyloxy)styrene and (triphenylphosphine)gold(I) chloride, which is the reverse of the formation of 3a.Gold(I) enolate undergoes an isocyanide insertion reaction into the linkage of carbon and gold. (2-Benzoylethyl)(triphenylphosphine)gold(I) reacts with 2-methyl-2-propanethiol to afford (triphenylphosphine)gold(I) t-butyl sulfide together with propiophenone.