Relationship of the Acid-Induced13C Chemical-Shift Change in the α-Carbon Atom to the Stretching Frequency of the Hydroxy Group in Saturated Alcohols

Abstract

Abstract A good linear relationship was found between the acid-induced 13C chemical shift change of the α-carbon atom and the OH stretching frequency of the hydroxy group in some saturated alcohols. The relationship is discussed with model calculations using the CNDO/2 method. The trifluoroacetic acid-induced 13C chemical shift change in the α-carbon atom to the hydroxy group, Δδ13c, has been measured for a number, of saturated alcohols in carbon tetrachloride solution and provides information on the relative basicity and its dependence on the structural factor.1 The free OH stretching frequency, vOHis known to depend on the structural factor of the substituent.2–5 We reported that a linear relationship exists between the 17 O chemical shift, δ17 O, and the OH stretching frequency of the hydroxy group in saturated alchohols, R-OH.5 In this case, the 17O chemical shift change was reported to be governed by the ionization potential.6 The ionization potential of R-OH is expected to be correlated with its bas...