A short and enantioselective preparation of taxol A-ring fragment

作者：Hirai Sho; Urushizako Naoko; Miyano Masayuki; Fujii Tomohiro; Nakada Masahisa^*

来源：Tetrahedron Letters, 2013, 54(14): 1888-1892.

DOI：10.1016/j.tetlet.2013.01.115

• Dihydroxylation
• Enantioselective
• Organocatalysis
• Stereoselective
• Taxol

Two short preparations of the taxol A-ring fragment are described: one via organocatalyzed alpha-aminoxylation and the other via Sharpless asymmetric dihydroxylation (SAD). The former approach affords the A-ring fragment in 10 steps, and the latter approach involves eight steps to afford the new A-ring fragment in 91% ee, which is made enantiomerically pure through recrystallization. The new A-ring fragment bearing a bromoalkene is confirmed to be useful to form the carbocyclic eight-membered ring of a taxol model compound by palladium-catalyzed intramolecular alkenylation.

• 出版日期2013-4-3