Direct Access to β-Trifluoromethyl-β-hydroxy Thioesters by Biomimetic Organocatalytic Enantioselective Aldol Reaction
作者:Jin Hyun Park、Jae Hun Sim、Choong Eui Song
DOI:10.1021/acs.orglett.9b01469
日期:2019.6.21
decarboxylative catalytic aldol reaction of trifluoromethyl ketones with malonic acid half-thioesters (MAHTs) is described. Utilizing cinchona-based thioureas as highly efficient polyketide synthase-mimic catalysts, chiral tertiary aldols, β-trifluoromethyl-β-hydroxy thioesters, were obtained in up to 99% yield and 95% ee. Facile transformation of the thioester moiety of the aldoladducts showcases the synthetic
A highly enantioselective synthesis of chiral β-hydroxy thioesters that uses a decarboxylative aldol reaction of malonicacid half thioesters and aldehydes catalyzed by a chloramphenicol base-derived bifunctional organocatalyst is reported. The resulting chiral β-hydroxy thioesters were obtained in high yields (up to 82%) with good to excellent enantioselectivities (up to 94% ee). The synthetic application
The organocatalytic enantioselective decarboxylative addition of malonic acid half thioesters to ketimines derived from isatins by using N‐heteroarenesulfonyl cinchonaalkaloid amides afforded products with high enantioselectivity. The products could be converted into optically active AG‐041R. X‐ray crystallographic analysis revealed that the hydrogen bonding between the sulfonimide proton and the
Mg2+-Imidazole-Catalyzed Self-Condensation of Malonyl Thioesters: Getting Tuned for Biomimetic Polyketide Synthesis?
作者:Naomi Sakai、Nathalie Sordé、Stefan Matile
DOI:10.3390/61100845
日期:——
We report that a subtle balance of carbanion reactivity, leaving group activation, and pKa of the catalyst is required for efficient self-condensation of thiomalonates to thioacetoacetates in up to 71% yield under “biomimetic” conditions originally proposed by Kobuke and Yoshida (Tetrahedron Lett. 1978, 19, 367).
我们报告说,在 Kobuke 和 Yoshida 最初提出的 "仿生 "条件下(Tetrahedron Lett.)
Exploiting Anion–π Interactions for Efficient and Selective Catalysis with Chiral Molecular Cages
作者:Na Luo、Yu‐Fei Ao、De‐Xian Wang、Qi‐Qiang Wang
DOI:10.1002/anie.202106509
日期:2021.9.13
direction to develop new and fundamental catalysis. For the appealing yet flexible π-face activation, can two or more π-acidic surfaces be manipulated for cooperative activation to achieve efficient transformation and particularly selectivity control is highly desirable. Here, we demonstrate a supramolecular π-catalysis strategy by establishing cooperative π-face activation in a confined electron-deficient