First Example of the Aza-Favorskii Reaction. Ethynylation of C=N Bond in the Superbasic System t-BuOK–DMSO

Russian Journal of Organic Chemistry - Direct ethynylation of ketimines with alkynes in the superbasic system t-BuOK–DMSO has been accomplished for the first time using the reaction of...     

Formation of 2-methyl-3,5-diphenylfuran from chalcone and acetylene in the system KOH–DMSO

Russian Journal of Organic Chemistry - Chalcone reacted with acetylene in a suspension of KOH in DMSO at 90°C (30 min) to give 36% of 2-methyl-3,5-diphenylfuran.     

Reaction of 1-vinylpyrrole-2-carbaldehydes with phosphorus pentachloride: a stereoselective synthesis of E-2-(2-dichloromethylpyrrol-1-yl)vinylphosphonyl dichlorides

1-Vinylpyrrole-2-carbaldehydes react with phosphorus pentachloride (benzene, 10-15 °C) to afford E-2-(2-dichloromethylpyrrol-1-yl)vinylphosphonium hexachlorophosphates in up to 85% yield, which after treatment with SO₂ (benzene, rt) are converted into E-2-(2-dichloromethylpyrrol-1-yl)vinylphosphonyl dichlorides in 50-75% yields.     

Chemoselective cross-coupling of terminal propargylamines with (het)aroyl chlorides: synthesis of β-aminoacetylenic ketones bearing aromatic and heteroaromatic substituents

Russian Chemical Bulletin - Terminal secondary 4-chlorophenyl propargylamines, synthesized by addition of acetylene to N-(4-chlorophenyl)ketimines (ButOK, DMSO, 20–25 °C) in 76–93%...     

Cascade assembly of frontalin derivatives from cyclohexanone and acetylene in the system KOH-DMSO

Russian Journal of Organic Chemistry -     

Consecutive Reactions of Dialkyl Ethynyl Carbinols with Acetylene in Superbase KOH/DMSO Suspension

2-Methylbut-3-yn-2-ol, a tertiary propargylic alcohol, reacts with acetylene under pressure in superbase KOH/DMSO suspension (80 °C, 1 h) to afford, along with the expected vinyl ether, 2,2,4,4-tetramethyl-5-methylidene-1,3-dioxolane, 2,5-dimethyl-5-(vinyloxy)hex-3-yn-2-ol and (Z)-2-methyl-4-(2-methylbut-3-yn-2-yloxy)but-3-en-2-ol.     

Improved synthesis of tertiary propargyl alcohols by the Favorskii reaction of alkyl aryl (hetaryl) ketones with acetylene

Alkyl aryl (hetaryl) ketones react with acetylene under atmospheric pressure in the superbasic system KOH-EtOH-H₂O-DMSO at 10–15°C (2 h) to give the corresponding tertiary propargyl alcohols in up to 91% yield. The procedure requires no large excess of KOH and low-boiling inflammable solvents, produces few wastes, and is safe and convenient on the laboratory scale; there are no limitations for its large-scale application.     

Reaction of phosphorus pentachloride with N-vinylimidazole and N-vinylbenzimidazole

Russian Journal of General Chemistry -