Enantioselective synthesis of functionalized pyrazoles by NHC-catalyzed reaction of pyrazolones with α,β-unsaturated aldehydes.
نویسندگان
چکیده
The N-heterocyclic carbene (NHC)-organocatalyzed enantioselective annulation reaction of pyrazolones with α,β-unsaturated aldehydes proceeding via the chiral α,β-unsaturated acyl azolium intermediates under oxidative conditions is presented. The reaction afforded dihydropyranone-fused pyrazoles in moderate to good yields and good er values under operationally simple and base-free conditions.
منابع مشابه
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ورودعنوان ژورنال:
- Organic letters
دوره 17 6 شماره
صفحات -
تاریخ انتشار 2015