['ANALYSIS', 'OF', 'TOBACCO', 'Nature', 'of', 'Hydrogen', 'Bonds', 'Formed', 'by', 'Phenol', 'Derivatives', 'and', 'N,', 'N-Dimethylaniline', 'in', 'Aprotic', 'Solvents', '-', 'Low-Temperature', 'NMR', 'Studies.', 'By', 'Ilezyszyn', 'M', 'Journal', 'of', 'the', 'Chemical', 'Society', '-', 'Faraday', 'Transactions;', '90', '(10)', 'pl411-1414', 'MAY', '21', '1994', 'ORDER', '#', 'NN456', 'dimethylaniline', 'to', 'produce', 'complexes', 'with', 'molecular', 'H-N-', ')', 'hydrogen', 'bonds.', 'The', 'degree', 'of', 'association', 'and', 'the', 'character', 'of', 'the', 'hydrogen', 'bonds', 'depends', 'strongly', 'on', 'the', 'solution', 'temperature', 'and', 'DELTApK(a)', '[=pK(a)', '(protonated', 'base)', '-', 'pK(a)', '(phenol)]', 'in', 'water.', 'The', 'tautomeric', 'equilibrium,', 'O-H...N', 'reversible', 'O-...H-N+,', 'which', 'is', 'slow', 'on', 'the', 'NMR', 'timescale,', 'has', 'been', 'recorded', 'in', 'the', '0.4', 'to', '-0.5', 'DELTApK(a)', 'range', 'below', '140', 'K.', 'Thermodynamic', 'and', 'kinetic', 'quantities', 'of', 'the', 'equilibrium', 'were', 'calculated', 'from', 'H-1', 'NMR', 'spectra', 'of', 'the', '2,3,5,6-tetrachlorophenol', 'complex.', 'The', 'thermodynamic', 'quantities', 'for', 'the', '2,6-dichloro-4-', 'nitrophenol', 'complex', 'were', 'obtained', 'from', 'C-13', 'NMR', 'results.', '(In', 'English)', 'Phenols', 'interact', 'with', 'NN-', '(O-H...N)', 'and', 'ion-pair', '(0-...', 'Reh', '80393988', 'Vol.', '24,', 'No.', '8,', 'July', '14,', '1994', 'i', 'Cro', 'a']