SYNTHESIS AND STRUCTURE OF 1-METALLA-2,3,4-TRIAZOLES OF MOLYBDENUM AND TUNGSTEN

The reaction of cyclopentadienyl substituted carbyne complexes of moly bdenum and tungsten C5H5(CO)2-n(PMe3)nM=C-R (M = Mo, W; R = C6H5, C6H4 CH3, CH3, n = 0, 1) (1a-3c) with azides N3R' (R' = CO2CH3, CH2CO2CH3) results in a [3 + 2]-cycloaddition to the electron-rich metal carbon t riple bond, producing neutral 1-metalla-2,3,4-triazole complexes C5H5( CO)2-n(PMe3)nM=C(R)-N=N-NR' (M = MO, W; R = C6H5, C6H4CH3, CH3, n = 0, 1) (4a-7c) in high yields. The new compounds were identified by X-ray structure analysis (5b), elemental analyses, NMR, IR and mass spectra .