STRUCTURE AND IR SPECTROSCOPIC BEHAVIOR OF THE ADDUCT OF 4-METHYLPYRIDINE WITH 2,6-DICHLORO-4-NITROPHENOL

The structure of the 4-methylpyridinium 2,6-dichloro-4-nitrophenolate(II) has been determined by X-ray diffraction. The crystals are triclinic, space group P1BAR, a = 7.366(1), b = 8.381(1), c = 11.624(2) angstrom, alpha = 72.45(1), beta = 76.39(1), gamma = 75.22(1)degrees and Z = 2. The structure has been solved by direct method and refined to R = 0.040 for 2238 independent reflections. The O-... H-N+ bridge of 2.604(3) angstrom with < OHN = 170(3)degrees is markedly longer than that of analogous complex composed of 3-methylpyridine indicating stronger charge separation. Accordingly no broad absorption in the fingerprint region is observed and a doublet characteristic of the N+H hydrogen bonded group is visible.