1-Bromo-2-trifluoroacetylcyclobutenes as novel building blocks for the construction of trifluoromethyl substituted heterocycles. Part 3: Synthesis of trifluoromethylsubstituted pyridines, condensed with cyclobutene moieties
作者:Andrey B. Koldobskii、Ekaterina V. Solodova、Ivan A. Godovikov、Pavel V. Verteletskii、Valery N. Kalinin
DOI:10.1016/j.jfluchem.2010.05.015
日期:2010.8
This paper describes a general synthetic approach to 3-cyano-4-trifluoromethylpyridines fused with cyclobutene rings with variable spiro conjunctions. The reaction of various 1-bromo-2-trifluoroacetylcyclobutenes with ammonia results in the substitution of bromine with an NH2 group leading to corresponding enaminoketones in high yields, which, in turn, form the target pyridines by treatment with diethyl