3-Alkenyl-5-chloropyrazoles: expedient synthesis via heterocyclization of 1,1-dichloro-4-halo-1-alken-3-ones with hydrazines
摘要:
Synthesis of hard-to-reach 5-chloro-3-alkenylpyrazoles was developed via heterocyclization of alkyl-, benzyl- or dialkylhydrazines with 1,1-dichloro-4-halo-1-alken-3-ones obtained from haloacyl chlorides and vinylidene chloride. The reaction process includes the formation of intermediate 5-chloro-3-(1-haloalkyl)pyrazoles followed by dehydrohalogenation. (C) 2011 Elsevier Ltd. All rights reserved.
3-Alkenyl-5-chloropyrazoles: expedient synthesis via heterocyclization of 1,1-dichloro-4-halo-1-alken-3-ones with hydrazines
作者:Galina G. Levkovskaya、Valentina A. Kobelevskaya、Elena V. Rudyakova、Khanh Q. Ha、Dmitrii O. Samultsev、Igor B. Rozentsveig
DOI:10.1016/j.tet.2011.01.028
日期:2011.3
Synthesis of hard-to-reach 5-chloro-3-alkenylpyrazoles was developed via heterocyclization of alkyl-, benzyl- or dialkylhydrazines with 1,1-dichloro-4-halo-1-alken-3-ones obtained from haloacyl chlorides and vinylidene chloride. The reaction process includes the formation of intermediate 5-chloro-3-(1-haloalkyl)pyrazoles followed by dehydrohalogenation. (C) 2011 Elsevier Ltd. All rights reserved.
Synthesis and reactions of 1-benzyl-3-haloalkyl-5-chloropyrazoles
作者:E. V. Rudyakova、V. A. Savosik、I. T. Evstaf’eva、E. V. Kondrashov、G. G. Levkovskaya
DOI:10.1134/s1070428009050108
日期:2009.5
pyrazoles reacted with indole and pyrrole in DMSO in the presence of alkali to give 3-(heter-1-yl)alkyl-substituted 1-benzyl-5-chloropyrazoles. 1-[(1-Benzyl-5-chloropyrazol-3-yl)methyl]indole reacted regiospecifically with chloroal trifluoromethylsulfonyl- and 4-chlorophenylsulfonylimines providing the products of C-amidotrichloroethylation into the position 3 of the indole ring. 1-[(1-Benzyl-5-c