Copper mediated stereoselective synthesis of C-glycosides from unactivated alkynes.
نویسندگان
چکیده
A highly stereoselective rapid C-glycosylation reaction has been developed between glycal and unactivated alkynes in the presence of coppertriflate and ascorbic acid at low catalyst loading and at room temperature. A wide variety of glycals and aryl acetylenes participate in the reaction smoothly. TfOH generated during the reduction of Cu(OTf)2 by ascorbic acid may be the active catalyst for the glycosylation.
منابع مشابه
Zinc mediated activation of terminal alkynes: stereoselective synthesis of alkynyl glycosides.
Zinc mediated alkynylation reaction was studied for the preparation of C-glycosides from unactivated alkynes. Different glycosyl donors such as glycals and anomeric acetates were tested towards an alkynyl zinc reagent obtained from alkynes using zinc dust and ethyl bromoacetate as an additive. The method provides simple, mild and stereoselective access to alkynyl glycosides both from aromatic a...
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عنوان ژورنال:
- Chemical communications
دوره 49 86 شماره
صفحات -
تاریخ انتشار 2013