Key Laboratory of Chemical Biology of Hebei Province, College of Chemistry and Environmental Science, Hebei University, Baoding 071002, People's Republic of China.
Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, People's Republic of China.
Org Lett. 2022 Aug 19;24(32):5929-5934. doi: 10.1021/acs.orglett.2c02180. Epub 2022 Aug 10.
An NHC-catalyzed enantio- and diastereoselective [3 + 2] annulation of α-bromoenals with bisoxindoles is developed, affording efficient access to various spirocyclic bisoxindole alkaloids. This protocol tolerates a broad substrates scope, with various spirocyclic bisoxindoles obtained in generally excellent enantioselectivities. More importantly, two contiguous sterically congested all-carbon quaternary stereocenters are successfully created during this process.
NHC 催化的α-溴代醛与双氧化吲哚的对映选择性和非对映选择性[3+2]环加成反应得到了各种螺环双氧化吲哚生物碱，这为高效构建各种螺环双氧化吲哚生物碱提供了一种新方法。该反应条件具有广泛的底物适用性，一般以优异的对映选择性得到各种螺环双氧化吲哚。更重要的是，在这个过程中成功地构建了两个相邻的空间位阻大的全碳季碳立体中心。
