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Download as PDF; Printable version; In other projects ... chemistry, alkynylation is an addition reaction in which a ... and liberate the free alcohol. [6] Scheme 1 ...
This alkynylation reaction is enantioselective and involves an alkynylzinc reagent [1] rather than the sodium acetylide used by John Ulric Nef in his 1899 report of the synthetic approach. [ 2 ] [ 3 ] Propargyl alcohols are versatile precursors for the chirally-selective synthesis of natural products and pharmaceutical agents , making this ...
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 coupling of a terminal alkyne and an aromatic ring is the pivotal reaction when talking about applications of the copper-promoted or copper-free Sonogashira reaction. The list of cases where the typical Sonogashira reaction using aryl halides has been employed is large, and choosing illustrative examples is difficult.
When bonded side-on to a single metal atom, an alkyne serves as a dihapto usually two-electron donor. For early metal complexes, e.g., Cp 2 Ti(C 2 R 2), strong π-backbonding into one of the π* antibonding orbitals of the alkyne is indicated.
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). [1] Alkylating agents are reagents for effecting alkylation. Alkyl groups can also be removed in a process known as dealkylation.
The Seyferth–Gilbert homologation is a chemical reaction of an aryl ketone 1 (or aldehyde) with dimethyl (diazomethyl)phosphonate 2 and potassium tert-butoxide to give substituted alkynes 3. [ 1 ] [ 2 ] Dimethyl (diazomethyl)phosphonate 2 is often called the Seyferth–Gilbert reagent .
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]