Efficient synthesis of optically active 4-nitro-cyclohexanones via bifunctional thiourea-base catalyzed double-Michael addition of nitromethane to dienones.
نویسندگان
چکیده
Thiourea-modified cinchona alkaloids as bifunctional catalysts and a base could catalyze a stepwise [5+1] cyclization of divinyl ketones with nitromethane via double Michael additions, furnishing optically active 4-nitro-cyclohexanones with good yields, excellent diastereoselectivities (>20 : 1) and high enantiomeric ratios (up to 97 : 3).
منابع مشابه
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ورودعنوان ژورنال:
- Chemical communications
دوره 47 13 شماره
صفحات -
تاریخ انتشار 2011