Superbase‐Promoted Selective Cascade Cyclization Reaction of 1, 5‐Diketones with Acetylenes to Methylene‐6, 8‐dioxabicyclo[3.2.1]octanes. Issue 12 (11th March 2013)

• Record Type: Journal Article
• Authors: Schmidt, Elena Yu.; Bidusenko, Ivan A.; Protsuk, Nadezhda I.; Ushakov, Igor A.; Trofimov, Boris A.
• Is Part Of: European journal of organic chemistry. Issue 12(2013)
• Page Start: 2453
• Page End: 2460
• Publication Date: 2013-03-11
• Subjects: Synthetic methods -- Domino ­reactions -- Diastereoselectivity -- Alkynes -- Oxygen heterocycles -- Ketones; Chemistry, Organic -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1002/ejoc.201201700
• Languages: English
• ISSNs: 1434-193X

Abstract

Abstract: 1, 5‐Diketones are readily cyclized in the presence of various alkali‐metal superbases with acetylenes at 70 °C in a one‐pot cascade reaction to give methylene‐6, 8‐dioxabicyclo[3.2.1]octanes in up to 92 % yield. In the case of symmetrical 1, 5‐diketones, only one diastereomer is formed, whereas unsymmetrical diketones afford two diastereomers in a ratio corresponding to that of the starting ketones. This result indicates the key cascade cyclization sequence is stereoselective. Abstract : From 1, 5‐diketones and acetylenes to polysubstituted methylene‐6, 8‐dioxabicyclooctanes, versatile building blocks and pheromones scaffold: a one‐pot transition‐metal‐free approach.