Regioselective Synthesis, NMR, and Crystallographic Analysis of N1-Substituted Pyrazoles
作者:Adrian Huang、Kellie Wo、So Yeun Christine Lee、Nika Kneitschel、Jennifer Chang、Kathleen Zhu、Tatsiana Mello、Laura Bancroft、Natalie J. Norman、Shao-Liang Zheng
DOI:10.1021/acs.joc.7b01006
日期:2017.9.1
A systematic study of the N-substitution reactions of 3-substituted pyrazoles under basic conditions has been undertaken. Regioselective N1-alkylation, -arylation, and -heteroarylation of 3-substituted pyrazoles have been achieved using K2CO3-DMSO. The regioselectivity is justified by the DFT calculations at the B3LYP/6-31G**(d) level. A consistent steric effect on chemical shift has been observed
对3-取代的吡唑在碱性条件下的N-取代反应进行了系统的研究。使用K 2 CO 3 -DMSO已经实现了3-取代的吡唑的区域选择性N1-烷基化,-芳基化和-杂芳基化。通过在B3LYP / 6-31G **(d)水平上的DFT计算可以证明区域选择性。对于N-烷基吡唑类似物,已经观察到对化学位移的一致的空间效应。已获得二十五个X射线晶体学结构,以确认主要产品的区域化学。