Structural investigation on phenyl- and pyridin-2-ylamino(methylene)naphthalen-2(3<i>H</i>)-one. Substituent effects on the NMR chemical shifts
作者:Taracad K. Venkatachalam、Gregory K. Pierens、Marc R. Campitelli、David C. Reutens
DOI:10.1002/mrc.2626
日期:2010.8
2-hydroxynaphthaldehyde. These Schiff bases were obtained as colored crystalline solids. The proton NMR spectra of these compounds showed a doublet for the NH protons indicating a keto tautomer for these Schiff bases. The pyridyl-substituted Schiff bases containing hydroxyl moiety were found to show the most downfield shift for the NH protons in DMSO solvent, and this was rationalized due to the formation of a
通过适当的胺与2-羟基萘醛的缩合合成带有苯基和吡啶基的席夫碱。得到这些席夫碱,为有色结晶固体。这些化合物的质子NMR光谱显示出NH质子的双峰,表明这些席夫碱的酮互变异构体。发现含有羟基部分的吡啶基取代的席夫碱对DMSO溶剂中的NH质子表现出最大的低场偏移,这是合理的,因为这两个化合物使用氢键形成了六元和五元环。相应地,由于与胺质子的偶联,还发现席夫碱的烯烃质子为双峰。这些席夫碱表现出热致变色性质。