Synthesis and unusual [2+2] cycloaddition reactions of haloacetylenes activated with the trifluoroacetyl group
作者:A. B. Koldobskii、N. P. Tsvetkov、P. V. Verteletskii、I. A. Godovikov、V. N. Kalinin
DOI:10.1007/s11172-009-0191-3
日期:2009.7
Halogenated trifluoroacetylacetylenes have been synthesized for the first time. It was shown that they undergo formally forbidden by the orbital-symmetry rules [2+2] cycloaddition reactions with nonactivated alkenes in the absence of light and catalyst. A possible mechanism for this transformation is suggested.
1-Bromo-2-trifluoroacetylcyclobutenes as novel building blocks for the construction of trifluoromethyl substituted heterocycles. Part 2: Synthesis of trifluoromethyl substituted thiophenes, condensed with cyclobutene moieties
作者:Andrey B. Koldobskii、Nikolay P. Tsvetkov、Ekaterina V. Solodova、Valery N. Kalinin
DOI:10.1016/j.jfluchem.2010.04.007
日期:2010.8
This paper describes a novel synthetic approach to 2-cyano-3-trifluoromethylthiophenes fused with cyclobutene rings with variable spiro conjunctions. The reaction of substituted 1-bromo-2-trifluoroacetylcyclobutenes with mercaptoacetonitrile results in the substitution of bromine with S-center to afford the corresponding nitriles in high yields, which form the target thiophenes by subsequent treatment
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
Universal method for the functionalization of β-bromovinyl trifluoromethyl ketones of cyclobutene series
作者:A. B. Koldobskii、N. P. Tsvetkov、V. N. Kalinin
DOI:10.1134/s0012500810050046
日期:2010.5
1-Bromo-2-trifluoroacetylcyclobutenes as novel building blocks for the construction of trifluoromethyl substituted heterocycles. Part 1: Synthesis of 5-(trifluoromethyl)-2(5H)-furanones condensed with substituted cyclobutenes
作者:Andrey B. Koldobskii、Nikolay P. Tsvetkov、Ekaterina V. Solodova、Valery N. Kalinin
DOI:10.1016/j.jfluchem.2010.03.006
日期:2010.6
reduction of substituted 1-bromo-2-trifluoroacetylcyclobutenes by lithium aluminiumhydride affords corresponding brominated alcohols, which, under the treatment of two equivalents of butyllithium, give new lithiated cyclobutenes. Their carboxylation followed by lactonization induced by trifluoroacetic anhydride appeared to be an effective approach towards 5-trifluoromethylated furanones condensed with substituted