HYDROGEN-BONDING IN 2-HYDROXY((DI)THIO)BENZOATES .3. IR AND NMR-SPECTRA OF 2,6-DIMETHYLPIPERIDINIUM AND TETRAETHYLAMMONIUM SALTS

Solid state ir and solution ir and nmr data are reported for 2,6-dimet hylpiperidinium and tetraethylammonium salts of 2-hydroxybenzoic, 2-hy droxythiobenzoic and 2-hydroxydithiobenzoic acid. The solid state nu(O H)BAR frequencies, range from 2800 to 2300 cm-1 and decrease within th e series thiocarboxylate (O-H...O) > dithiocarboxylate (O-H...S) > car boxylate (O-H...O) > thiocarboxylate (O-H...S), reflect the different kinds of intramolecular O-H...Y association. The solution nu(OH)BAR fr equencies range from 2830 to 2560 cm-1 and decrease within the series thiocarboxylate > dithiocarboxylate > carboxylate; the delta(OH) proto n shifts range from 12.8 to 16.0 ppm and correspondingly increase with in the same series. IR and NMR data give confident evidence for an O-H ...O intramolecular association of the thiocarboxylate anions in solut ion.