Carbon-13 NMR chemical shifts of 1-alkyl-3(5)-cyano-1H-pyrazole-4-carboxylic acid esters
作者:George E. Babbitt、Michael P. Lynch、James R. Beck
DOI:10.1002/mrc.1260280117
日期:1990.1
A compilation of 13C NMR chemical shifts for 13 pairs of 3‐ and 5‐cyano‐substituted pyrazole regioisomers is reported. All of the ring carbon and cyano carbon 13C chemical shifts show a regular, predictable correlation with the particular isomer, whether 3‐cyano or 5‐cyano. These shifts occurred in very narrow ranges, precluding any confusion of assignment within the group of compounds studied. x‐ray
报告了 13 对 3-和 5-氰基取代的吡唑区域异构体的 13C NMR 化学位移的汇编。所有环碳和氰基碳 13C 化学位移都显示出与特定异构体(无论是 3-氰基还是 5-氰基)的规则的、可预测的相关性。这些变化发生在非常窄的范围内,排除了所研究化合物组内的任何分配混淆。对其中一个样品进行 X 射线晶体学分析。