Nickel-Catalyzed Double Bond Transposition of Alkenyl Boronates for in Situ syn-Selective Allylboration Reactions.
نویسندگان
چکیده
The transposition of a homoallyl pinacol boronic ester was realized by a highly reactive nickel-catalyst system comprising NiCl2(dppp), zinc powder, ZnI2, and Ph2PH. The in situ generated Z-crotyl pinacol boronic esters were reacted with various aldehydes to form syn-homoallylic alcohols in high diastereoselectivities. The present nickel-catalyzed reaction is complementary to the iridium-catalyzed transposition reported by Murakami leading to the corresponding anti-homoallylic alcohols. Also, the multiple transposition of pentenyl pinacol boronic ester was realized.
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ورودعنوان ژورنال:
- Organic letters
دوره 18 3 شماره
صفحات -
تاریخ انتشار 2016