Kinetics and Mechanism of the Formation of Palladium Bis(benzylamine) Complexes from Reaction of Benzylamine with Palladium Tri-o-tolylphosphine Mono(amine) Complexes

Journal Article (Journal Article)

The kinetics of the conversion of the palladium mono(benzylamine) complex Pd[P(o-tol) ](p-C H CMe )[H -NBn]Br (2) to the bis(benzylamine) complex Pd(p-C H CMe [H NBn] Br (3) established the second-order rate law: Rate = k [2][H NBn], where ΔH = 13.8 ± 0.3 kcal mol and ΔS = -29.7 ± 0.8 eu. Kinetics were consistent with a mechanism initiated by direct attack of benzylamine on 2 via an associative or interchange mechanism. Benzylamine exchange with both 2 and 3 was > 1.5 × 10 times faster than conversion of 2 to 3 under comparable conditions. Complex 2 underwent phosphine exchange in the presence of P(1-naphthyl) to form Pd[P(1-naphthyl) ](p-C H CMe )[H NBn]Br (9). Kinetics of the conversion of 9 to 2 were consistent with associative solvolysis of 9 to form Pd[P(1-naphthyL) ](p-C H CMe )[solvent]Br (V) followed by attack of P(o-tolyl) to form the mixed bis(phosphine) intermediate Pd[P(o-tol) ][P(1-naphthyl) ](p-C H CMe )Br (VI). Solvolytic displacement of P(o-tolyl) from VI followed by reaction with amine would then form 2. 3 6 4 3 2 6 4 3 2 2 1 2 3 3 6 4 3 2 3 6 4 3 3 3 3 6 4 3 3 ‡ -1 ‡ 3

Full Text

Duke Authors

Cited Authors

  • Zhong, HA; Widenhoefer, RA

Published Date

  • January 1, 1997

Published In

Volume / Issue

  • 36 / 12

Start / End Page

  • 2610 - 2616

International Standard Serial Number (ISSN)

  • 0020-1669

Digital Object Identifier (DOI)

  • 10.1021/ic961388v

Citation Source

  • Scopus