Carbamoyl anion addition to N-sulfinyl imines: highly diastereoselective synthesis of α-amino amides.
نویسندگان
چکیده
Carbamoyl anions, generated from N,N-disubstituted formamides and lithium diisopropylamide, add with high diastereoselectivity to chiral N-sulfinyl aldimines and ketimines to provide α-amino amides. The methodology enables the direct introduction of a carbonyl group without the requirement of unmasking steps as with other nucleophiles. The products may be converted to α-amino esters or 1,2-diamines. Iterative application of the reaction enabled the stereoselective synthesis of a dipeptide. Spectroscopic and computational studies support an anion structure with η(2) coordination of lithium by the carbonyl group.
منابع مشابه
Highly diastereoselective addition of the lithium enolate of alpha-diazoacetoacetate to N-sulfinyl imines: enantioselective synthesis of 2-oxo and 3-oxo pyrrolidines.
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عنوان ژورنال:
- Journal of the American Chemical Society
دوره 135 15 شماره
صفحات -
تاریخ انتشار 2013