Schwartsburd, L., Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 76100, Israel
Poverenov, E., Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 76100, Israel
Shimon, L.J.W., Unit of Chemical Research Support, Weizmann Institute of Science, Rehovot, 76100, Israel
Milstein, D., Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 76100, Israel

A series of naphthyl-based PCP Pt(II) complexes was synthesized and characterized. A single-crystal X-ray study of (PCP)PtCl (2) reveals stacking of the aromatic units between each pair of molecules of 2. Chloride abstraction from 2 under nitrogen atmosphere leads to formation of the unsaturated cationic complex [(PCP)Pt]+BF4 - (3), with the metal center being stabilized by the counteranion (3a) or by the solvent (3b). Abstraction of the chloride ligand from 2 under CO atmosphere leads to formation of the cationic carbonyl complex [(PCP)Pt(CO)]+BF4 - (4), containing an electrophilic carbonyl ligand. The latter is attacked by nucleophiles (MeO- and H-) to give the platinum carbomethoxy complex 5 and a rare platinum formyl complex, 6. Stabilized by the bulky bis-chelating tridentate pincer-type system, the formyl complex 6 was isolated and characterized. Complex 6 is more stable than the previously reported platinum formyls. At room temperature complex 6 is slowly converted (during days) into a hydride complex, 7. © 2007 American Chemical Society.