Efficient synthesis of 5-substituted-3-pyridazine carbonitrile via regioselective Reissert-type reaction
摘要:
Various 5-substituted-3-pyridazine carbonitrile derivatives were synthesized by regioselective Reissert-type reaction with 4-substituted pyridazine, 4-methylbenzene-1-sulfonyl chloride and trimethylsilyl cyanide. The reaction can be carried out under conditions of AlCl3 as catalyst, THF as solvent at 10 degrees C, followed by treatment with DBU which gave moderate yields and good regioselectivity. (C) 2016 Elsevier Ltd. All rights reserved.
Radical-Based Regioselective C–H Functionalization of Electron-Deficient Heteroarenes: Scope, Tunability, and Predictability
作者:Fionn O’Hara、Donna G. Blackmond、Phil S. Baran
DOI:10.1021/ja406223k
日期:2013.8.14
of substituents exert consistent and additive effects on the regioselectivity of substitution. This allowed us to establish guidelines for predicting regioselectivity on complex π-deficient heteroarenes, including pyridines, pyrimidines, pyridazines, and pyrazines. Since the relative contribution from opposing directing factors was dependent on solvent and pH, it was sometimes possible to tune the regiochemistry