Synthesis, coordination and reactivity of 2-(trimethylsiloxymethyl)phenyl- and 2-(hydroxymethyl)phenyl isocyanides

2-(Trimethylsiloxymethyl)phenyl isocyanide, 2-(CH2OSiMe3)C6H4NC (2) was prepared by reaction of 2-(trimethylsiloxymethyl)phenyl formamide, 2-(CH2OSiMe3)C6H4NHCHO (1) with trichloromethyl chloroformate. Reaction of 2 with F− ions in MeOH leads to the formation of 2-(hydroxymethyl)phenyl isocyanide, 2-(CH2OH)C6H4NC (3), which is stable as free ligand and does not spontaneously undergo intramolecular cyclization to 4H-benzo[1,3]oxazine. The isocyanide 2 coordinates to Pt(II) and Pd(II) metal ions such as in the complexes cis-[MCl2(CNC6H42-CH2OSiMe3)2] and cis-[PdCl2(CNC6H4-2-CH2OSiMe3)(PPh3)], which are converted to the corresponding benzoxazin-2-ylidene derivatives and , respectively, in the presence of a catalytic amount of F− ions in MeOH. On the other hand, coordination of 2 to the {M(CO)5} (M=W, Cr) fragments and subsequent reactions with of F− ions in MeOH affords the corresponding 2-(hydroxymethyl)phenyl isocyanide complexes [M(CO)5(CNC6H42-CH2OH)], where the hydroxy function does not react with the coordinated isocyanide group.