Abstract
A (PNP)-P-3 pincer ligand (1) bearing dicyclopentylphosphine substituents reacts with [Rh(COD) Cl](2) (COD = 1,5-cyclooctadiene) to produce the complex ((PNP)-P-3) RhCl (2). Treatment of a benzene solution of 2 with KN(SiMe3) 2 stimulates a dearomatization process, and C-H activation of benzene is achieved through the rearomatization of the central pyridine ring. This deprotonation/reprotonation of the NH arm of 2 gives the phenyl complex ((PNP)-P-3) Rh(C6H5) (3). The subsequent introduction of CO gas into 3 yields the benzoyl complex ((PNP)-P-3) RhCO (C6H5) (4), which can release benzaldehyde upon treatment with diluted HCl solution and regenerates 2.