A Lewis acid activated reaction of Zn with EtI to promote highly enantioselective alkyne additions to aldehydes.
نویسندگان
چکیده
An easily available BINOL-Ti(O(i)Pr)4 catalyst system is found to activate the reaction of Zn powder with EtI for the asymmetric alkyne addition to aldehydes at room temperature. It allows the synthesis of a number of synthetically useful chiral propargylic alcohols with both high yields and high enantioselectivity (up to >96% ee).
منابع مشابه
Dual Lewis acid–Lewis base activation in enantioselective additions to aldehydes*
Reaction of benzaldehyde with ethyl cyanoformate in the presence of Lewis acidic Ti(IV) complexes of bispyridylamide or salen ligands and Lewis basic amines affords the O-alkoxycarbonylated cyanohydrin. In the presence of the salen-based catalytic system, acetyl cyanide can also be added to benzaldehyde, providing a highly enantioselective direct route to the O-acetylated cyanohydrin.
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ورودعنوان ژورنال:
- Chemical communications
دوره 51 2 شماره
صفحات -
تاریخ انتشار 2015