Enantioselective Synthesis of 5-Alkylated Thiazolidinones via Palladium-Catalyzed Asymmetric Allylic C–H Alkylations of 1,4-Pentadienes with 5<i>H</i>-Thiazol-4-ones
作者:Tian-Ci Wang、Zhi-Yong Han、Pu-Sheng Wang、Hua-Chen Lin、Shi-Wei Luo、Liu-Zhu Gong
DOI:10.1021/acs.orglett.8b01697
日期:2018.8.17
A palladium-catalyzed, enantioselective allylic C–H alkylation of 1,4-pentadienes with 5H-thiazol-4-ones has been developed. Under the cooperative catalysis of a palladium complex of chiral phosphoramidite ligand and an achiral Brønstedacid, a broad range of substituted 5H-thiazol-4-ones bearing sulfur-containing tertiary chiral centers were accessed from the allylic C–H alkylation in high levels
Palladium-catalyzed asymmetric allylic C-H alkylation of 1,4-dienes and glycine Schiff bases
作者:Tian-Ci Wang、Pu-Sheng Wang、Liu-Zhu Gong
DOI:10.1007/s11426-019-9687-1
日期:2020.4
Abstract A highly regio- and enantioselectiveallylicC-Halkylation of 1,4-dienes with glycine Schiff bases has been established by chiral palladium-phosphoramidite catalysis. This reaction can proceed under mild conditions and tolerate a wide scope of 1,4-dienes, delivering structurally diverse chiral β-branched a-amino acid surrogates in moderate to high yields and with high levels of regio-, Z/E-
Construction of Multiring Frameworks by Metal-Free Cascade Reactions of Stable Isochromenylium Tetrafluoroborate
作者:Zhi-Long Hu、Wen-Jian Qian、Sheng Wang、Shaozhong Wang、Zhu-Jun Yao
DOI:10.1021/jo902051g
日期:2009.11.20
Efficient methodologies for constructing several multiring frameworks have been developed utilizing the cascade reactions of air-stable isochromenylium tetrafluoroborates with olefins. Successive additions of two equivalents of styrene-type olefins to isochromenylium tetrafluoroborate (ICTB) I have been observed and their mechanisms were proposed and discussed. Intramolecular capture of the early stage cat ionic intermediates by predevised heteroatoms or Friedel-Crafts donors provided two different types of bridged-ring systems.