Читать книгу Catalytic Asymmetric Synthesis - Группа авторов - Страница 33

Bicyclo[4.3.0]none derivatives, which are C and D rings of the steroids, were synthesized as a single isomer with excellent enantioselectivity by diphenylprolinol silyl ether mediated Michael reaction of nitroalkane possessing a diketone moiety and an α,β‐unsaturated aldehyde, followed by aldol reaction (Eq. 1.33). This domino reaction was used as a key reaction for the total synthesis of estradiol methyl ether, which was synthesized using five reaction vessels with four purifications [61].

(1.33)