Asymmetric Hydrogenation of Ketones and Enones with Chiral Lewis Base Derived Frustrated Lewis Pairs
作者:Bochao Gao、Xiangqing Feng、Wei Meng、Haifeng Du
DOI:10.1002/anie.201914568
日期:2020.3.9
The concept of frustratedLewispairs (FLPs) has been widely applied in various research areas, and metal-free hydrogenation undoubtedly belongs to the most significant and successful ones. In the past decade, great efforts have been devoted to the synthesis of chiral boron Lewis acids. In a sharp contrast, chiral Lewisbase derived FLPs have rarely been disclosed for the asymmetric hydrogenation.
Formal [4 + 1] annulation of fluorinated sulfonium salt with cyclic unsaturated imines to access CF<sub>3</sub>-substituted pyrroles
作者:Tao Chen、Aoning Wang、Linxue Zhang、Chenlong Wei、Juhui Huang、Xiang Liu、Zhenqian Fu
DOI:10.1039/d1ob00218j
日期:——
Formal [4 + 1] annulation of easily available fluorinated sulfonium salt with cyclic unsaturated imines has been successfully developed. A structurally diverse set of CF3-substituted dihydropyrroles was efficiently constructed in acceptable to excellent yields with excellent diastereoselectivities. The resulting CF3-containing dihydropyrroles from this transition metal-free strategy could be easily
Enantioselective phospha-Michael reaction of diethyl phosphonate with exocyclic α,β-unsaturated benzocyclic ketones catalyzed by a dinuclear zinc−AzePhenol catalyst
作者:Na Shao、Yong-Yang Luo、Hui-Jie Lu、Yuan-Zhao Hua、Min-Can Wang
DOI:10.1016/j.tet.2018.03.016
日期:2018.4
The dinuclear zinc complexes as high performance catalysts were used to catalyze phospha-Michael reaction of exocyclic α,β-unsaturated benzocyclic ketones under mild conditions, and the desired products possessing 1-indanones or 1-tetralones skeleton were obtained with excellent enantioselectivities of up to 99%/99% ee and yields of up to 99%. The absolute stereochemistry of the major products catalyzed
Highly Enantioselective Epoxidation of Multisubstituted Enones Catalyzed by Non‐Heme Iron Catalysts
作者:Bin Wang、Shoufeng Wang、Chungu Xia、Wei Sun
DOI:10.1002/chem.201200992
日期:2012.6.11
Iron(II) efficiency: The iron complexes of N4 ligands, derivedfrom proline and benzimidazole, exhibited an unprecedented activity and enantioselectivity for the epoxidation of a variety of di‐ and trisubstituted enones (see scheme). This system, based on synthetic non‐heme iron catalysts, provides ready access to a wide range of epoxyketones of high enantiomeric purity.
Evaluation of Silica-H2SO4 as an Efficient Heterogeneous Catalyst for the Synthesis of Chalcones
作者:Aeysha Sultan、Abdul Raza、Muhammad Abbas、Khalid Khan、Muhammad Tahir、Nazamid Saari
DOI:10.3390/molecules180810081
日期:——
We report an efficient silica-H2SO4 mediated synthesis of a variety of chalcones that afforded the targeted compounds in very good yield compared to base catalyzed solvent free conditions as well as acid or base catalyzed refluxing conditions.