Metal-Free Catalytic Asymmetric Fluorination of Keto Esters Using a Combination of Hydrogen Fluoride (HF) and Oxidant: Experiment and Computation
作者:Roman Pluta、Patricia E. Krach、Luigi Cavallo、Laura Falivene、Magnus Rueping
DOI:10.1021/acscatal.7b03118
日期:2018.3.2
for the catalytic asymmetric fluorination has been developed. The catalyst was used in the asymmetric fluorination of carbonyl compounds, providing the products with a quaternary stereocenter with high enantioselectivities. Chiral hypervalent iodine difluoride intermediates were generated in situ by treatment of the catalyst with an oxidant and hydrogen fluoride as fluoride source. As such, the α-fluorination
Construction of Vicinal All-Carbon Stereogenic Centers via Copper-Catalyzed Asymmetric Decarboxylative Propargylation: Enantio- and Diastereoselective Synthesis of Substituted Spirolactones
The formation of vicinal all-carbonquaternarystereocenters remains a formidable challenge. We report herein the synthesis of such highly congested structural dyads by copper-catalyzed decarboxylative propargylation between propargyl carbonates and indanone-based nucleophiles. The implementation of diphenylethylenediamine (DPEN)-based ligands is the key to success. A wide range of functional groups
Palladium-Catalyzed Stereoselective Construction of 1,3-Stereocenters Displaying Axial and Central Chirality via Asymmetric Alkylations
作者:Aiqi Xue、Xingfu Wei、Yue Huang、Jingping Qu、Baomin Wang
DOI:10.3390/molecules28072927
日期:——
challenge. Herein, we report the development of stereoselective union of a point chiral center with allenyl axial chirality in 1,3-position by Pd-catalyzed asymmetric allenylic alkylation between racemic allenyl carbonates and indanone-derived β-ketoesters. Various target products bearing a broad range of functional groups were afforded in high yield (up to 99%) with excellent enantioselectivities (up to
Redetermination of the Structure of a Water-Soluble Hypervalent Iodine(V) Reagent AIBX and Its Synthetic Utility in the Oxidation of Alcohols and Synthesis of Isoxazoline <i>N</i>-Oxides
作者:Hui-Jie Shen、Ya-Nan Duan、Ke Zheng、Chi Zhang
DOI:10.1021/acs.joc.9b02328
日期:2019.11.15
obtained by adding a Brønstedacid, which was supported by the calculation result including the increase of Mayer bond order and the shortening of the I-O bond length. Moreover, the fact that the system of AIBX and TFA could oxidize various alcohols to their corresponding carbonyl compounds would indicate that AIBX constitutes a cyclic benziodoxole structure underacidicconditions. In addition, an efficient
The enantioselective Claisenrearrangement of allenyl vinyl ethers was realized to access branched 1,3-dienyl-substituted all-carbon quaternary stereocenters using a NiII-N,N[prime or minute]-dioxide complex.
实现了烯基乙烯基醚的对映选择性克莱森重排,以使用Ni II - N,N [伯或分钟]-二氧化物络合物接近支链的1,3-二烯基取代的全碳季立体中心。