Different hybridized oxygen atoms controlled chemoselective formation of oxocarbenium ions: synthesis of chiral heterocyclic compounds
作者:Xiao-Na Wu、Zhi-Hao You、Yan-Kai Liu
DOI:10.1039/c8ob01743c
日期:——
Based on the electronic properties of different hybridized oxygenatoms (sp3versus sp2) in the structure of O,O-acetals containing an enol ether moiety, the chemoselective formation of oxocarbenium ions was realized to furnish diversified chiral heterocyclic compounds with excellent stereoselectivities by reacting with different types of nucleophiles. Additionally, an unexpected intramolecular oxocarbenium
Organocatalytic Asymmetric Synthesis of Spiro-Bridged and Spiro-Fused Heterocyclic Compounds Containing Chromane, Indole, and Oxindole Moieties
作者:Zhi-Hao You、Ying-Han Chen、Yu Tang、Yan-Kai Liu
DOI:10.1021/acs.orglett.8b02731
日期:2018.11.2
applied to the asymmetric synthesis of spiro-bridged and spiro-fused heterocyclic compounds, which combined chromane, indole, and oxindole, three potential pharmacophores, in one molecule. The power of these two organocatalytic pathways is underscored by mild reaction conditions and high efficiency in the production of synthetically challenging, but biologically important heterocyclic products, which could
Organocatalyst-Mediated Dynamic Kinetic Enantioselective Acylation of 2-Chromanols
作者:Daniel A. Glazier、John M. Schroeder、Jitian Liu、Weiping Tang
DOI:10.1002/adsc.201800994
日期:2018.12.3
We recently developed a novel chiral catalyst‐directed dynamic kinetic diastereoselective acylation of hemiacetals for the synthesis of carbohydrates. In this update, we describe a catalytic method for the dynamic kinetic enantioselective acylation of 2‐chromanols using benzotetramisole derived catalysts. High yields and enantiomeric excesses were obtained for a broad range of acylated 2‐chromanols
One-pot, highly efficient, asymmetric synthesis of ring-fused piperidine derivatives bearing N,O- or N,N-acetal moieties
作者:Ji-Yao Li、Zhi-Long Li、Wei-Wei Zhao、Yan-Kai Liu、Zhi-Ping Tong、Rui Tan
DOI:10.1039/c5ob02571k
日期:——
successfully expand the application of lactols or cyclic hemiaminals as nucleophiles for the asymmetric synthesis of both N,O- and N,N-acetal moieties contained in the structure of ring-fused piperidinederivatives. This efficient one-pot protocol involves an organocatalyzed asymmetric aza-Diels–Alder reaction and iminium ion induced cyclization sequence to ultimately deliver heterocyclic compounds with excellent
The Important Role of the Byproduct Triphenylphosphine Oxide in the Magnesium(II)-Catalyzed Enantioselective Reaction of Hemiacetals and Phosphorus Ylides
作者:Linqing Wang、Dongxu Yang、Dan Li、Xihong Liu、Pengxin Wang、Kezhou Wang、Haiyong Zhu、Lutao Bai、Rui Wang
DOI:10.1002/anie.201804177
日期:2018.7.16
By employing a simple in situ generated magnesium catalyst, a direct asymmetric reaction between hemiacetals and phosphorusylides was achieved through a tandem Wittig–oxa‐Michael reaction sequence. Enantioenriched chromans, isochromans, and tetrahydropyrans were obtained in good chemical yields, and (−)‐erythrococcamide B was synthesized in enantioenriched form. The byproduct triphenylphosphine oxide