19780-12-2Relevant articles and documents
Alkylation of Terminal Alkynes under Zinc Lewis Acid Catalysis and Its Mechanistic Studies
Osano, Mana,Kida, Takeru,Yonekura, Kyohei,Tsuchimoto, Teruhisa
supporting information, p. 2825 - 2831 (2019/04/13)
With a zinc Lewis acid catalyst and proton sponge in toluene, terminal alkynes were found to undergo the alkylation by alkyl triflates to provide unsymmetrical internal alkynes. This is the first example that a simple alkyl chain other than benzylic and norbornyl units can be introduced onto the alkynyl carbon atom under Lewis acid catalysis. Mechanistic studies revealed that the activation of the alkyne by the zinc Lewis acid and proton sponge is the trigger of the reaction to give a monoalkynylzinc species, which successively reacts with the alkyl triflate to afford the internal alkyne. A radical pathway is unlikely in this system. (Figure presented.).
Selective Coupling Reactions of Alkynyl(phenyl)iodonium Tosylates with Alkynylcopper Reagents
Kitamura, Tsugio,Tanaka, Toshimasa,Taniguchi, Hiroshi,Stang, Peter J.
, p. 2892 - 2893 (2007/10/02)
Alkynyl(phenyl)iodonium tosylates react with mixed cuprates coordinated by alkynyl components to give unsymmetrical diacetylenes selectively; the coupling reaction with dialkylcuprates afforded substituted alkynes.
Reactions with Phosphine Alkylenes, XLII. A Sequence for the Preparation of Acetylenes Starting from Carboxylic Chlorides and Phosphorus Ylides via 1,2-Diketones.
Bestmann, Hans Juergen,Kumar, Kamlesh,Kisielowski, Lothar
, p. 2378 - 2382 (2007/10/02)
Phosphorus ylides 1 and carboxylic chlorides 2 react with transylidation to give acyl ylides 3 which are oxidized with the adduct of ozone to triphenyl phosphite to yield 1,2-diketones 5.These are converted into the bis(hydrazones) 6 which are oxidized with O2/CuCl in pyridine giving acetylenes 7.
