title: Catalytic Asymmetric Addition of Alkyl and Aryl Alkynes to N-(Diphenylphosphinoyl)imines.
abstract: A 3,3'-di(1-diphenylmethylpiperazinyl)methyl H8BINOL compound, (S)-11, was prepared from the Mannich-type reaction of (S)-H8BINOL with paraformaldehyde and 1-(diphenylmethyl)piperazine. This compound can catalyze the asymmetric reaction of alkyl and aryl alkynes with N-(diphenylphosphinoyl)imines in the presence of Et2Zn and Ti(OiPr)4. It exhibits unprecedented high enantioselectivity (up to 85% ee) for a simple alkyl alkyne addition to the N-(diphenylphosphinoyl)imines. The easy removal of the N-(dipehenylphosphinoyl) protecting groups makes this method practically useful for the asymmetric synthesis of chiral propargyl amines.
authors: Department of Chemistry, University of Virginia , Charlottesville, Virginia 22904-4319, United States.
authors: Jun
authors: J
authors: Ying
authors: Department of Chemistry, University of Virginia , Charlottesville, Virginia 22904-4319, United States.
authors: Xue-Dan
authors: XD
authors: Wu
authors: Department of Chemistry, University of Virginia , Charlottesville, Virginia 22904-4319, United States.
authors: Danny
authors: D
authors: Wang
authors: Department of Chemistry, University of Virginia , Charlottesville, Virginia 22904-4319, United States.
authors: Lin
authors: L
authors: Pu