title: One-ligand catalytic asymmetric deprotonation of a phosphine borane: synthesis of P-stereogenic bisphosphine ligands.
abstract: A new protocol for the catalytic asymmetric deprotonation of a phosphine borane using s-BuLi and substoichiometric quantities of chiral diamines is reported. The method involves three sequential additions of s-BuLi, and use of (-)-sparteine or the (+)-sparteine surrogate facilitates access to P-stereogenic phosphines with opposite configuration. The method is exemplified by the catalytic asymmetric synthesis of each enantiomer of precursors to QuinoxP*, trichickenfootphos, and Mini-PHOS.
authors.affiliation: Department of Chemistry, University of York, Heslington, York, United Kingdom.
authors.forename: Johan
authors.initials: J
authors.lastname: Granander
authors.forename: Francesco
authors.initials: F
authors.lastname: Secci
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Canipa
authors.forename: Peter
authors.initials: P
authors.lastname: O'Brien
authors.forename: Brian
authors.initials: B
authors.lastname: Kelly