Synthesis and solution structure of palladium tris(o-tolyl)phosphine mono(amine) complexes

Journal Article (Journal Article)

The complex(es) resulting from a 1:4 mixture Of Pd (DBA) and P(o-tol) react with aryl bromides or aryl iodides p-XC H R (X = Br, I; R = Me, t-Bu, OMe) to generate the corresponding halide dimers {Pd[P(o-tol) ](p-C H R)(μ-X)} (X = Br, R = t-Bu (1), Me (2), OMe (3); X = I, R = t-Bu (4), Me (5), OMe (6)) in 46-76% yield. Iodide dimer 5 reacts with AgOTf in acetonitrile to form the cationic bis(acetonitrile) complex {Pd[P(o-tol) ](p-C H -Me)(CH CN) ]} OTf (8) which was treated in situ with LiCl to form the chloride dimer {Pd[P(o-tol) ](p-C H Me)(μ-Cl)} (9) in 93% yield. The p-tolyl halide dimers 2, 5, and 9 react with N-benzylmethylamine to generate the corresponding 1:1 palladium amine adducts Pd[P(o-tol) ](p-C H Me)[HN(Me)Bn]X (X - Cl (12), 85%; X = Br (13), 72%; X = I (14), 77%). Reaction of a mixture of Pd (DBA) and P(o-tol) with the haloamines 2-IC H (CH ) N(H)Bn, 2-BrC H CH N(H)(p-tolyl), and 2-BrC H (CH ) N(H)Bn gave the chelated palladium amine complexes Pd[P(o-tol) ](2-C H (CH ) N(H)Bn]I (18, 71%), Pd[P(o-tol) ][2-C H CH N(H)(p-tolyl)]Br (19, 77%), and Pd[P(o-tol) ](2-C H (CH ) N(H)Bn]Br (21, 24%), respectively. Variable-temperature H and P NMR analysis of 12-14 and related complexes was consistent with hindered rotation about the P-C bonds, with predominant formation of the exo -P(o-tol) conformer, and hindered rotation about the Pd-P bond with formation of three unequally populated rotamers. 2 3 3 6 4 3 6 4 2 3 6 4 3 2 3 6 4 2 3 6 4 2 3 3 6 4 2 2 6 4 2 6 4 2 3 3 6 4 2 2 3 6 4 2 3 6 4 2 3 2 + - 1 31

Full Text

Duke Authors

Cited Authors

  • Widenhoefer, RA; Zhong, HA; Buchwald, SL

Published Date

  • June 11, 1996

Published In

Volume / Issue

  • 15 / 12

Start / End Page

  • 2745 - 2754

International Standard Serial Number (ISSN)

  • 0276-7333

Digital Object Identifier (DOI)

  • 10.1021/om9509599

Citation Source

  • Scopus