Competitive Intramolecular Hydrogen Bonding in Oligo(ethylene oxide) Substituted Quadruple Hydrogen Bonded Systems
作者:Tom F. A. de Greef、Marko M. L. Nieuwenhuizen、Rint P. Sijbesma、E. W. Meijer
DOI:10.1021/jo902053t
日期:2010.2.5
A series of oligo(ethylene oxide) (oligoEO) substituted 2-ureido-pyrimidinones (UPy), differing in the number of ethylene oxide units and the length of the aliphatic spacer connecting the oligoEO side chain with the UPy group, have been prepared. It was found that variation in these structural parameters strongly influences the dimerization constant (Kdim) of the UPy dimer and the association constant
已经制备了一系列的低聚(环氧乙烷)(oligoEO)取代的2-脲基-嘧啶酮(UPy),其环氧乙烷单元的数目和连接低聚EO侧链与UPy基团的脂族间隔基的长度不同。发现这些结构参数的变化强烈影响UPy二聚体的二聚化常数(K dim)和缔合常数(K a)。)UPy与2,7-diamido-1,8-naphthyridine(NaPy)在氯仿中的溶液。通过分析二聚化强度,脂族间隔基的长度和oligoEO链中EO单元数之间的关系,我们提供了强有力的证据表明氢键强度的降低是由于oligoEO链的醚原子之间竞争性的分子内氢键引起的。 UPy单元的氢键供体。