An entry to a chiral dihydropyrazole scaffold: enantioselective [3 + 2] cycloaddition of nitrile imines.
نویسندگان
چکیده
We have developed a versatile strategy to access dihydropyrazoles in highly enantioenriched form. Dipolar cycloaddition of electron-deficient acceptors and in situ-generated nitrile imines proceeds with high regio- and enantioselectivity using 10 mol % chiral Lewis acid catalyst. A variety of dihydropyrazoles that incorporate functionality for further manipulation have been prepared.
منابع مشابه
Chiral bis(imidazolidine)pyridine-cu complex-catalyzed enantioselective [3+2]-cycloaddition of azomethine imines with propiolates.
[3+2] Cycloaddition of azomethine imines with electron-deficient terminal alkynes was smoothly catalyzed by a chiral bis(imidazolidine)pyridine-CuOAc complex to give bicyclic pyrazolo[1,2-a]pyrazolone derivatives with up to 74% ee.
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ورودعنوان ژورنال:
- Journal of the American Chemical Society
دوره 127 23 شماره
صفحات -
تاریخ انتشار 2005