Premium
Cyclopalladated Compounds with Polyhalogenated Benzylphosphanes for the Mizoroki‐Heck Reaction
Author(s) -
LópezMosquera Cristina,
Grabulosa Arnald,
Rocamora Mercè,
FontBardia Mercè,
Muller Guillermo
Publication year - 2020
Publication title -
european journal of inorganic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.667
H-Index - 136
eISSN - 1099-0682
pISSN - 1434-1948
DOI - 10.1002/ejic.202000288
Subject(s) - chemistry , bromobenzene , medicinal chemistry , heck reaction , cationic polymerization , bromide , palladium , catalysis , tetrafluoroborate , ligand (biochemistry) , dimer , polymer chemistry , organic chemistry , ionic liquid , biochemistry , receptor
Nine partially halogenated benzylphosphanes Ar X CH 2 PR 2 (Ar X = 3,6‐dichlorophenyl, 3,6‐difluorophenyl and 3,4,5‐trifluorophenyl; R = Ph, Cy, i Pr) have been prepared and reacted with palladium acetate to obtain the cyclometallated dimers [Pd( µ ‐OAc)(κ 2 ‐ C,P ‐Ar X CH 2 PR 2 )] 2 . The acetate bridge has been exchanged by bromide using lithium bromide and the obtained dimers have been thoroughly characterised. The dimers with the non‐halogenated phosphanes PhCH 2 PR 2 (R = Ph, i Pr) have also been prepared. Treatment with norbornadiene in the presence of silver tetrafluoroborate has furnished the cationic mononuclear complexes [Pd(κ 2 ‐ C,P ‐Ar X CH 2 PR 2 )(nbd)]BF 4 as stable solids. These complexes and some of the bromide dimers have been used as catalytic precursors in the Mizoroki‐Heck reaction between bromobenzene and butyl acrylate. The complexes efficiently catalyse this transformation and important differences of activity are found depending on the ligand. In general, fluorinated phosphanes give more active systems than chlorinated analogues.