title: A highly efficient, practical, and general route for the synthesis of (R3P)2Pd(0): structural evidence on the reduction mechanism of Pd(II) to Pd(0).
abstract: A highly efficient, practical, and general method was developed to synthesize a family of (R(3)P)(2)Pd(0) complexes, using a stoichiometric amount of phosphine ligands and readily available Pd(II) precursors. The stepwise pathway of reducing Pd(II) to Pd(0) was established by isolating two key intermediates. Both [t-Bu(2)(4-Me(2)NC(6)H(4))P](2)Pd and (t-Bu(2)NpP)(2)Pd are new compounds. Preliminary studies on [t-Bu(2)(4-Me(2)NC(6)H(4))P](2)Pd have indicated that it is a very active catalyst (84-95% isolated yield) in the Cu-free Sonogashira coupling involving aryl and heteroaryl chlorides at 0.5 mol % catalyst loading.
authors.affiliation: Johnson Matthey Catalysis and Chiral Technologies, 2001 Nolte Drive, West Deptford, New Jersey 08066, USA.
authors.forename: Hongbo
authors.initials: H
authors.lastname: Li
authors.forename: Gabriela A
authors.initials: GA
authors.lastname: Grasa
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Colacot