Proton NMR and IR study of self-association in pyridylalkanols: open or cyclic dimers? higher polymers?
作者:John S. Lomas、Alain Adenier、Christine Cordier
DOI:10.1002/poc.1056
日期:2006.5
The IR spectra of 3-(X-pyridyl)-2,2,4,4-tetramethylpentan-3-ols (X = 3 or 4) in carbon tetrachloride suggest weak association, while the 2-pyridyl derivative occurs mainly as the intramolecularly hydrogen-bonded rotamer. The OH NMR shifts for the 3- and 4-pyridyl derivatives in benzene are concentration-dependent, but neither the equilibrium constants nor the degree of association can be evaluated
1 H NMR测量表明,通式为(C 5 H 4 N)(CH 2)n OH的(X-吡啶基)烷醇,其中n = 1、2或3,它们自缔合为开放二聚体,环状二聚体,三聚体和四聚体,其变化取决于烷基链的位置及其长度。2-(X-吡啶基)丙-2-醇的行为类似于相应的吡啶基甲醇,但是具有较低的缔合常数。四氯化碳中3-(X-吡啶基)-2,2,4,4-四甲基戊基-3-醇(X = 3或4)的红外光谱表明缔合较弱,而2-吡啶基衍生物主要以分子内形式存在氢键旋转异构体。苯中的3-吡啶基和4-吡啶基衍生物的OH NMR位移与浓度有关,但是平衡常数和缔合度均无法评估。苯中的苄醇与开环二聚体和环状四聚体缔合,而2-苯基丙烷-2-醇则更弱。-1。版权所有©2006 John Wiley&Sons,Ltd.