Catalytic highly asymmetric 1,5(6)-selective cyclization reaction of α-hydroxyimino cyclic ketones: direct approach to ring-fused hydroxyimino dihydropyrans.
نویسندگان
چکیده
Herein, we have disclosed a catalytic asymmetric 1,5(6)-selective Michael/cyclization reaction of α-hydroxyimino cyclic ketones with γ,β-unsaturated α-keto esters. Unlike the previous catalytic strategies, this reaction provides a convenient 1,5(6)-selective asymmetric pathway to access synthetically useful ring-fused dihydropyrans. In general, high levels of yield, enantio- and diastereoselectivity (up to 99% yield, >99% ee and >20 : 1 dr) were obtained.
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 11 32 شماره
صفحات -
تاریخ انتشار 2013