Concise assembly of 7-ethynyl-6, 8-dioxabicyclo[3.2.1]octanes from acetylenes and ketones. Issue 15 (27th March 2023)

• Record Type: Journal Article
• Authors: Schmidt, Elena Yu.; Bidusenko, Ivan A.; Protsuk, Nadezhda I.; Ushakov, Igor A.; Trofimov, Boris A.
• Is Part Of: Organic & biomolecular chemistry. Volume 21:Issue 15(2023)
• Page Start: 3183
• Page End: 3202
• Publication Date: 2023-03-27
• Subjects: Chemistry, Organic -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1039/d3ob00252g
• Languages: English
• ISSNs: 1477-0520

Abstract

Abstract : A new family of natural-related bicyclic ketals became readily accessible in a simple atom-economic two-step procedure from acetylenes and ketones under mild transition-metal-free conditions. Abstract : 2-Acetyl-3, 4-dihydropyrans, assembled from acetylene gas and ketones in a one-pot procedure, are ethynylated with acetylenes (KOBu t /DMSO, 15 °C, 2 h) to give acetylenic alcohols, which readily cyclize (TFA, rt, 5 min) to 7-ethynyl-6, 8-dioxabicyclo[3.2.1]octanes in up to 92% yield. The ring closure of the above acetylenic alcohols can be performed without their isolation from the reaction mixture. Thus, the synthesis of 7-ethynyl-6, 8-dioxabicyclo[3.2.1]octanes can be realized in just two synthetic operations from simple and available starting materials under mild transition-metal-free conditions.