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

2-(Trimethylsiloxymethyl)phenyl isocyanide, 2-(CH-2OSiMe3)C(6)H(4)NdropC (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)C(6)H(4)NdropC (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(11) 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 [MCl2(CN(H)C6H4-2-CH2O)(2)] and [PdCl2(CN(H)C6H4-2-CH2O)(PPh3)], respectively, in the presence of a catalytic amount of F- ions in MeOH. On the other hand, coordination of 2 to the M(CO)51 (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. (C) 2002 Elsevier Science B.V. All rights reserved.