The Structure of Pyrazoles in the Solid State: A Combined CPMAS, NMR, and Crystallographic Study
作者:Rosa M. Claramunt、Pilar Cornago、Verónica Torres、Elena Pinilla、M. Rosario Torres、André Samat、Vladimir Lokshin、Magali Valés、José Elguero
DOI:10.1021/jo0609935
日期:2006.9.1
The structures of six N-unsubstituted pyrazoles, three already known and three newly synthesized, have been studied by a combination of X-ray crystallography, multinuclear NMR (solution and solid state), and density functional theory (DFT) calculations. In those cases where crystal structure and CPMAS NMR were available, the agreement was almost perfect, allowing a prediction of the tautomer (with
通过结合X射线晶体学,多核NMR(溶液和固态)和密度泛函理论(DFT)计算,研究了6种N-未取代的吡唑的结构,其中3种是已知的,而3种是新合成的。在那些晶体结构和CPMAS NMR可用的情况下,该协议几乎是完美的,对于5-异丙基-3-苯基-1而言,可以预测互变异构体(具有确定性)和四聚体结构(具有很高的可能性)。H-吡唑,不知道X射线结构。在5-(2-苄基苯基)-3-三氟甲基-1 H的情况下如上所示-吡唑,在B3LYP / 6-31G **水平上的DFT计算通过存在于溶液中的分子内NH-··π相互作用证明了该互变异构体的巨大稳定性。