One method for synthesizing ynones is the acyl substitution reaction of an alkynyldimethylaluminum with anacyl chloride. An alkynyldimethylaluminum compound is the reaction product oftrimethylaluminum and a terminalalkyne.[1]
Synthesis of an ynone
An alternative is the direct coupling of anacyl chloride with a terminal alkyne, using a copper-based nanocatalyst:[2]
Synthesis of an ynone
Other methods utilize an oxidative cleavage of analdehyde, followed by reaction with a hypervalent alkynyl iodide, using a gold catalyst.[3]
An alternative but longer synthetic method involves the reaction of an alkynyllithium compound with an aldehyde. The reaction produces a secondary alcohol that then can be oxidized via theSwern oxidation.
Terminal alkynes add across α,β-unsaturated ketones in the presence of palladium catalysts. The reaction affords γ,δ-ynones.[4] Terminal alkynes add across epoxides to given yneols, which can be oxidized to give β,γ-ynones.[5]
^Wang, Baomin; Bonin, Martine; Micouin, Laurent (June 22, 2005). "A Straightforward Synthesis of Ynones by Reaction of Dimethylalkynylaluminum Reagents with Acid Chlorides".J. Org. Chem.70 (15):6126–6128.doi:10.1021/jo050760y.PMID16018717.
^Weijiang, Sun; Wang, Yan; Wua, Xuan; Yao, Xiaoquan (2013). "Palladium-, ligand-, and solvent-free synthesis of ynones by the coupling of acyl chlorides and terminal alkynes in the presence of a reusable copper nanoparticle catalyst".Green Chemistry.15 (9):2356–2360.doi:10.1039/c3gc40980e.
^Wang, Zhaofeng; Li, Li; Yong, Huang (August 18, 2014). "A General Synthesis of Ynones from Aldehydes via Oxidative C–C bond Cleavage under Aerobic Conditions".J. Am. Chem. Soc.136 (35):12233–12236.doi:10.1021/ja506352b.PMID25133731.
^Adam Sniady, Marco S. Morreale, Roman Dembinski (2007). "Electrophilic Cyclization with N-Iodosuccinimide: Preparation of 5-(4-Bromophenyl)-3-Iodo-2-(4-Methyl-Phenyl)Furan".Organic Syntheses.84: 199.doi:10.15227/orgsyn.084.0199.{{cite journal}}: CS1 maint: multiple names: authors list (link)
^Wills, M.S.B.;Danheiser, R.L. (August 28, 1998). "Intramolecular [4 + 2] Cycloaddition Reactions of Conjugated Ynones. Formation of Polycyclic Furans via the Generation and Rearrangement of Strained Heterocyclic Allenes".J. Am. Chem. Soc.120 (36):9378–9379.doi:10.1021/ja9819209.
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