Chiral Naphthyl-C2-Indole as Scaffold for Phosphine Organocatalysis: Application in Asymmetric Formal [4 + 2] Cycloaddition Reactions
作者:Tingting He、Lei Peng、Shan Li、Fangli Hu、Chuandong Xie、Shengli Huang、Shiqi Jia、Wenling Qin、Hailong Yan
DOI:10.1021/acs.orglett.0c02519
日期:2020.9.4
naphthyl-C2-indole bifunctional phosphine organocatalyst in stereoselective formal [4 + 2] cycloadditionreactions were reported. The chiral naphthyl-C2-indole skeleton was introduced to bifunctional phosphine organocatalysis for the first time, and excellent stereocontrol was achieved in two types of formal [4 + 2] cycloadditionreactions. With the optimal catalyst, a series of chiral spirooxindole and hydrodibenzofuran
Enantioselective Synthesis of Multifunctionalized 4<i>H</i>-Pyrans via Formal [4 + 2] Annulation Process by Bifunctional Phosphonium Salt Catalysis
作者:Jia-Hong Wu、Jianke Pan、Juan Du、Xiaoxia Wang、Xuemei Wang、Chunhui Jiang、Tianli Wang
DOI:10.1021/acs.orglett.9b04079
日期:2020.1.17
highly enantioselective formal [4 + 2] annulation involving electron-deficient allenes as C2-synthons has been developed under bifunctional phosphonium salt catalysis. With this catalytic protocol, a wide range of synthetically interesting and highly functionalized chiral 4H-pyran derivatives were readily prepared in good yields (up to 99%) with outstanding diastereo- and enantioselectivities (up to
Remote Control of Axial Chirality: Synthesis of Spirooxindole–Urazoles via Desymmetrization of ATAD
作者:Lin-Lin Zhang、Ji-Wei Zhang、Shao-Hua Xiang、Zhen Guo、Bin Tan
DOI:10.1021/acs.orglett.8b02361
日期:2018.10.5
control of axial chirality in an asymmetric three-component reaction. This transformation was realized by a tandem bisthiourea-catalyzed asymmetric Diels–Alder reaction and substrate-controlled asymmetric enereaction. The driving force derived from aromatization and the high reactivity of 4-aryl-1,2,4-triazole-3,5-dione enophiles mediated the occurrence of the successive enereaction under mild conditions
An Asymmetric Diels-Alder Reaction Catalyzed by Chiral Phosphate Magnesium Complexes: Highly Enantioselective Synthesis of Chiral Spirooxindoles
作者:Guilong Li、Tao Liang、Lukasz Wojtas、Jon C. Antilla
DOI:10.1002/anie.201209295
日期:2013.4.22
Mild Magic: A mild, enantioselectiveDiels–Alderreaction, catalyzed by a chiral magnesium phosphate species, has been developed for the synthesis of various chiral spirooxindoles. Molecular sieves were found to have a considerable effect when used as additives in this reaction.
A chiral N,N’-dioxide/Co(BF4)2•6H2O complex catalytic system has been developed to efficiently catalyze the asymmetric1,3-dipolarcycloaddition of nitrones with methyleneindolinones. The corresponding chiral multisubsitituted spiroisoxazolidines with three contiguous quaternary-tertiary stereocenters were obtained in moderate to high yields with excellent dr and ee values (up to 97% yield, >19:1 dr