Enantioselective Syntheses of Tricyclic Benzimidazoles via Intramolecular Allylic Aminations with Chiral-Bridged Biphenyl Phosphoramidite Ligands
Enantioselective Syntheses of Tricyclic Benzimidazoles via Intramolecular Allylic Aminations with Chiral-Bridged Biphenyl Phosphoramidite Ligands
复制标题
手性桥连联苯亚磷酰胺配体通过分子内烯丙基胺化对映选择性合成三环苯并咪唑
DOI：
10.1021/acs.orglett.8b03640
复制
发表时间：
2019
期刊：
影响因子：
5.2
通讯作者：
Qiu Liqin
中科院分区：
文献类型：
--
作者：
Jiang Xiaoding;Chen Xiangmeng;Li Yongsu;Liang Hao;Zhang Yaqi;He Xiaobo;Chen Bin;Chan Wesley Ting Kwok;Chan Albert S. C.;Qiu Liqin
首次报道了铱催化的苯并咪唑系烯丙基碳酸酯的不对称分子内烯丙基胺化反应，高产率地合成了3类含叔碳立体中心的三环苯并咪唑类化合物，对映选择性高达99%（产率99%ee）。广泛的底物范围，优异的催化效率和温和的条件使该协议特别上级和实用。令人印象深刻的是，具有可调结构的手性桥被证明为手性环境提供了一个非常好的调节空间。配体的优异催化性能表明了它们在这些转化中优于双酚基和BINOL衍生的对应物。同时也突出了手性桥联配体的潜在应用价值。
The first iridium-catalyzed enantioselective intramolecular allylic aminations of benzimidazole-tethered allylic carbonates were developed, providing three classes of tricyclic benzimidazoles bearing a tertiary carbon stereogenic center in high yields and excellent enantioselectivities (up to 99% yield, 99% ee). Wide substrate scope, excellent catalytic efficiency and mild conditions rendered this protocol particularly superior and practical. Impressively, the chiral bridge with a tunable structure was shown to provide a very good adjustment space for the chiral environment. The excellent catalytic performance of the ligands manifested their advantages over the bisphenol-based and BINOL-derived counterparts in these transformations. It also highlighted the potential application value of the chiral-bridged ligands.