Palladium-catalyzed C–P(III) bond formation reaction with acylphosphines as phosphorus source
作者:Rongrong Yu、Xingyu Chen、Zhiqian Wang
DOI:10.1016/j.tetlet.2016.06.088
日期:2016.7
Palladium-catalyzed C–P(III) bond formation reaction employing acylphosphines as the phosphorus source was developed. Under the optimized conditions, acylphosphines could react with aryl halides directly affording trivalent phosphines in up to 94% yield.
promoted by Lewis acids or Brønsted acids. In this work, a novel acylation of arenes with a highlyelectrophilic acylphosphonium salt was developed. The alkylation of the phosphorus atom in acylphosphines generated a neutral trivalent phosphine as a good leaving group and triggered the high electrophilicity of the acylphosphonium salt. Using acylphosphonium salts, 38 examples of acylations of arenes
Enantioselective reduction of acylphosphines, after precomplexation with borane, proceeded smoothly in the presence of a chiral oxazaborolidine catalyst and catecholborane. alpha-Hydroxyalkylphosphine products were obtained as phosphineborane complexes in good yield and enantioselectivity. One of the products of the enantioselective reduction was successfully applied as an optically active phosphine ligand for asymmetric catalysis after suitable derivatization.