Asymmetric Synthesis of Dihydrocoumarins Containing Contiguous Quaternary and Tertiary Stereogenic Centers Catalyzed by a Cinchona-Alkaloid-Based Bifunctional Thiourea Derivative
Asymmetric Synthesis of Dihydrocoumarins Containing Contiguous Quaternary and Tertiary Stereogenic Centers Catalyzed by a Cinchona-Alkaloid-Based Bifunctional Thiourea Derivative
复制标题
金鸡纳生物碱双功能硫脲衍生物催化不对称合成含有连续四级和三级立体中心的二氢香豆素
DOI：
10.1002/adsc.201500666
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发表时间：
2016-01-07
影响因子：
5.4
通讯作者：
Wang, Xing-Wang
中科院分区：
文献类型：
--
作者：
Zhang, Shao-Yun;Lv, Ming;Wang, Xing-Wang
以奎宁衍生的硫脲为双功能有机催化剂，通过吖内酯与邻羟基查尔酮的多米诺不对称Michael加成/酯交换反应，有效地合成了一系列对映体富集的含有连续的四级和三级立体异构中心的3，4-二氢香豆素.在温和的反应条件下，一般以63-96%的产率获得光学活性的3，4-二氢香豆素，其中dr> 20：1，ee为81-96%。
A series of enantiomerically enriched 3,4-dihydrocoumarins containing contiguous quaternary and tertiary stereogenic centers has been efficiently constructed via domino asymmetric Michael addition/transesterification reactions of azlactones with o-hydroxychalcones using a quinine-derived thiourea as bifunctional organocatalyst. Under mild reaction conditions, the optically active 3,4-dihydrocoumarins were generally obtained in 63-96% yields with > 20:1 dr and 81-96% ee.