Amine-Functionalized Indazolin-3-ylidene Complexes of Palladium(II) by Postmodification of a Single Precursor

作者：Bernhammer Jan C; Singh Harvenjit; Han Vinh Huynh^*

来源：Organometallics, 2014, 33(16): 4295-4301.

DOI：10.1021/om5006275

A series of five trans-[PdBr2(amine)(indy)] complexes (amine = diethylamine, dipropylamine, dibutylamine, diisobutylamine, morpholine; indy = indazolin-3-ylidene) with pendant teriary amine functionalities in the side chain of the NHC ligand has been prepared by postcoordinative modification of a single bromoalkyl-functionalized precursor complex. This approach allows for a synthesis of functionalized N-heterocyclic carbene complexes more efficient than the metalation of prefunctionalized azolium salts. All complexes have been fully characterized, and the molecular structures of three complexes are reported. A correlation exists between the C-13 NMR shift of C-carbene and the pK(b) values of the coordinated amines. Furthermore, all complexes were found to be active catalysts for the direct arylation of 1-methylpyrrole with good to excellent yields.

• 出版日期2014-8-25