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Several modifications of alkynylation reactions are known: In the Arens–van Dorp synthesis the compound ethoxyacetylene [7] is converted to a Grignard reagent and reacted with a ketone, the reaction product is a propargyl alcohol.
The reaction medium must be basic to neutralize the hydrogen halide produced as the byproduct of this coupling reaction, so alkylamine compounds such as triethylamine and diethylamine are sometimes used as solvents, but also DMF or ether can be used as solvent. Other bases such as potassium carbonate or cesium carbonate are occasionally used.
Typical route for alkylation of benzene with ethylene and ZSM-5 as a heterogeneous catalyst. Alkylation is a chemical reaction that entails transfer of an alkyl group. The alkyl group may be transferred as an alkyl carbocation, a free radical, a carbanion, or a carbene (or their equivalents).
English: Diagram showing the chemical reaction involving Sonogashira reaction of a phenylalanine derivative with an alkyne. Modified from File:Alkynylation.gif to correct chemical errors. Date
The Corey–Fuchs reaction, also known as the Ramirez–Corey–Fuchs reaction, is a series of chemical reactions designed to transform an aldehyde into an alkyne. [1] [2] [3] The formation of the 1,1-dibromoolefins via phosphine-dibromomethylenes was originally discovered by Desai, McKelvie and Ramirez. [4]
The Favorskii reaction is an organic chemistry reaction between an alkyne and a carbonyl group, under basic conditions. The reaction was discovered in the early 1900s by the Russian chemist Alexei Yevgrafovich Favorskii. [1] Favorskii reaction and the possible subsequent rearrangement
The Hay coupling is variant of the Glaser coupling. It relies on the TMEDA complex of copper(I) chloride to activate the terminal alkyne. Oxygen (air) is used in the Hay variant to oxidize catalytic amounts of Cu(I) to Cu(II) throughout the reaction, as opposed to a stoichiometric amount of Cu(II) used in the Eglington variant. [7]
The alkyne zipper reaction is an organic reaction that involves isomerization of a non terminal alkyne into a terminal alkyne. This reaction was first reported by Alexey Favorsky in 1887 (J. Russ. Phys.-Chem. Soc., 19, 414 (1887)). Also, this reaction was reported by Charles Allen Brown and Ayako Yamashita in 1975. [1]