Bicyclic N-heterocyclic carbene (NHC) ligand precursors and their palladium complexes

Abstract Eight bicyclic amidinium precursors (3), prepared from R,S-tmcp (R,S-tmcp: (1R,3S)-diamino-1,2,2-trimethylcyclopentane) were described. Only five of the precursors (3a–e) could be converted to palladium complexes, (PdX2(6,7-NHC)PEPPSI) (4) by treatment with PdCl2, K2CO3, and pyridine (additional KBr was used for (PdBr2(6,7-NHC)PEPPSI)). The salts and complexes were fully characterized by spectroscopic methods and X-ray crystallography.

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