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Paper | Special issue | Vol 99, No. 2, 2019, pp.1251-1275
Published online, 27th February, 2019
DOI: 10.3987/COM-18-S(F)99
Diastereo–/Enantioselective Diels–Alder Synthesis of 14β-Hydroxysteroid Scaffolds: A Combined Experimental and DFT Study

Clovis Peter, Philippe Geoffroy, Takatsugu Murata, Takayuki Tonoi, Isamu Shiina,* and Michel Miesch*

*Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan

Abstract

Natural, non-natural and ent-14β-hydroxyandrostane derivatives closely related to the cardenolide and bufadienolide skeletons were readily available through highly diastereo-/enantioselective Diels–Alder reactions calling for high pressure or Lewis acid activation. Moreover, in the presence of (R)- or (S)-carvone as chiral dienophile, the Diels–Alder reaction took place under chemodivergent parallel kinetic resolution control. Based on experimental and DFT studies, reasonable mechanism insights were postulated to explain the concave/convex and endo/exo selectivities observed for the formation of the different Diels–Alder and Diels–Alder–Michael adducts.