Enantioselective intermolecular bromoesterification of allylic sulfonamides
作者:Wei Zhang、Na Liu、Casi M. Schienebeck、Xin Zhou、Izarin I. Izhar、Ilia A. Guzei、Weiping Tang
DOI:10.1039/c3sc50446h
日期:——
Highly enantioselective intermolecular bromoesterification of alkenes was achieved for the first time. Both C–O and C–Br bonds were introduced enantioselectively in this olefin addition reaction. The sulfonamide NH directing group is important for both the reactivity and enantioselectivity.
Copper‐Catalyzed Azide–Ynamide Cyclization to Generate α‐Imino Copper Carbenes: Divergent and Enantioselective Access to Polycyclic N‐Heterocycles
作者:Xin Liu、Ze‐Shu Wang、Tong‐Yi Zhai、Chen Luo、Yi‐Ping Zhang、Yang‐Bo Chen、Chao Deng、Rai‐Shung Liu、Long‐Wu Ye
DOI:10.1002/anie.202007206
日期:2020.10.5
Here an efficient copper‐catalyzed cascade cyclization of azide‐ynamides via α‐imino copper carbene intermediates is reported, representing the first generation of α‐imino copper carbenes from alkynes. This protocol enables the practical and divergent synthesis of an array of polycyclic N‐heterocycles in generally good to excellent yields with broad substrate scope and excellent diastereoselectivities
A facile TfOH-catalyzed oxidative cyclization of allyl compounds and isocyanide has been developed with the assistance of DDQ, where isocyanide is used as the crucial "N" and "CN" sources. Highly functionalized 2-cyanopyrroles are constructed efficiently through a new formal [3 + 2] mode, demonstrating diverse reactivity and synthetic utility in organic chemistry. 2-Cyanopyrrole is converted into a