Copper-catalyzed stereoselective alkylhydrazination of alkynes
Jian Lei1, Huaxin Gao1, Miaoling Huang1
1College of Chemical Engineering and Materials Science, Quanzhou Normal University, Quanzhou 362000, P. R. China. leijian0902@hotmail.com xxl_qztc@163.com.
Abstract:
An unprecedented Cu-catalyzed stereoselective alkylhydrazination reaction involving terminal alkynes, azocarboxylic esters as a nitrogen source, and dimethyl 2,2'-azobis(2-methylpropionate) and its analogues as a carbon source is presented here. This protocol provides direct access to tri-substituted (E)-alkenyl-hydrazines with good regio- and stereoselectivity under mild conditions. The transformation proceeds without an external oxidant or additives and shows good functional group tolerance. The alkenylhydrazine products could be easily converted into valuable 1,4-dicarbonyl and allyl carboxylic derivatives.
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