Reductive methylenation of ketones to give allyl alcohols

Russian Chemical Bulletin -     

Formation of free radicals in the vinylation of 2-substituted pyrroles with acetylenes in a KOH-DMSO system

By spin trapping, using 2-methyl-2-nitrosopropane (t-BuNO), the EPR signals of vinyl-tert-butylnitroxyls and spin adducts of t-BuNO with products of the addition of 2-substituted pyrrole radicals to acetylenes were recorded during the vinylation of 2-substituted pyrroles with acetylenes in a KOH-DMSO system. The 2-substituted pyrrole radicals have a high stability, and their EPR spectra were observed directly in the vinylation reactions. It is shown that one-electron transfer processes are involved in vinylation.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1056–1062, August, 1992.     

One-electron transfer in the vinylation of 4,5,6,7-tetrahydroindole with acetylenes in the system KOH-DMSO

It has been shown by EPR, using 2-methyl-2-nitrosopropane as a radical trap, that vinylation of 4,5,6,7-tetrahydroindole with phenylacetylene in the system KOH-DMSO involves the formation of the 4,5,6,7-tetrahydroindolyl radical by transfer of an electron from the 4,5,6,7-tetrahydroindole anion to the acetylene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 142–144, January, 1990.     

Alkenylation by 5-hexen-2-one oxime: Prototropic isomerization under trofimov reaction conditions

From 5-hexene-2-one oxime (I) and acetylene in KOH/DMSO, 2-methyl-3-(2-propenyl)pyrrole (II), E- and Z-2-methyl-3-(1-propenyl)pyrroles (III), and E- and Z-1-vinyl-2-methyl-3-(1-propenyl)pyrroles (V) were synthesized. The isomerization of the alkenyl radical of pyrroles II was studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 477–480, April, 1992.     

Synthesis of Functionalized 2-(2-Pyrrolyl)pyrazolo[1,5-a]pyrimidines

Reactions of 5-amino-3-(2-pyrrolyl)pyrazoles with -dicarbonyl compounds (acetylacetone and ethyl acetoacetate) lead to formation of up to 90% of polysubstituted pyrazolo[1,5-a]pyrimidines.     

The “one pot” synthesis of 4,5-dihydrobenzo[g]indole and its 1-vinyl derivative from 1-tetralone,hydroxylamine, and dichloroethane in the system KOH-DMSO

4,5-Dihydrobenzo[g]indole and its 1-vinyl derivative were obtained from 1-tetralone, hydroxylamine, and dichloroethane in the superbasic system KOH-DMSO (140 °C, 3 h) in a total yield of 88%. The proposed method provides a fire-safe and explosion-proof approach to indole derivatives in demand.     

Synthesis of secondary propargyl alcohols from aromatic and heteroaromatic aldehydes and acetylene in the system KOH-H2O-DMSO

Ethynylation of aromatic and heteroaromatic aldehydes with acetylene under atmospheric pressure in the catalytic system KOH-H₂O-DMSO (aldehyde-KOH molar ratio 1 : 2, ?5 to ?7°C, 3 h) gave secondary propargyl alcohols in 46–67% yield.