Enantioselective organocatalytic Michael addition of malonate esters to nitro olefins using bifunctional cinchonine derivatives.
نویسندگان
چکیده
A family of 9-amino(9-deoxy) epicinchonine derivatives, possessing a range of mono- and bidentate hydrogen bond donor groups at the 9-position, were synthesised and evaluated for asymmetric organocatalytic activity in the dimethyl malonate Michael addition to beta-nitrostyrene; thiourea derivative was identified as the most effective bifunctional organic catalyst and found to induce high enantioselectivity in the malonate ester Michael addition reaction to a range of nitro olefins.
منابع مشابه
Organocatalytic enantioselective Michael addition of a kojic acid derivative to nitro olefins.
By employing a chiral bifunctional thiourea-tertiary amine as catalyst, enantioselective Michael addition of a kojic acid derivative to nitro olefins was realised. The reactions afforded the products with good yields (up to 99%) in good enantioselectivities (up to 97% ee). In addition, the absolute configuration of one product was determined.
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عنوان ژورنال:
- Chemical communications
دوره 35 شماره
صفحات -
تاریخ انتشار 2005