Pd-Catalyzed Decarboxylative Olefination: Stereoselective Synthesis of Polysubstituted Butadienes and Macrocyclic P-glycoprotein Inhibitors
作者:Bichao Song、Peipei Xie、Yingzi Li、Jiping Hao、Lu Wang、Xiangyang Chen、Zhongliang Xu、Haitian Quan、Liguang Lou、Yuanzhi Xia、K. N. Houk、Weibo Yang
DOI:10.1021/jacs.0c00078
日期:2020.6.3
The efficient and stereoselective synthesis of polysubstituted butadienes, especially the multifunctional butadiene, represents a great challenge in organic synthesis. Herein, we wish to report a distinctive Pd(0) car-bene-initiated decarboxylative olefination approach that enables the direct coupling of diazo esters with vinylethylene carbonates (VECs), vinyl oxazolidinones, or vinyl benzoxazinones
carbonaceous materials (SW) by perchloric acid catalyzed coupling reactions between diazo compounds and arylboronic acids was developed. The reaction shows a high level of functional tolerance and a broad substrate scope. Furthermore, the highly selective 1,2-alkyl shift products were furnished through the sterically demanding R4, R5 migration of diazo compounds (3-diazochromanone). The structures of 1,2-shift
Blue Light-Emitting Diode-Mediated <i>In Situ</i> Generation of Pyridinium and Isoquinolinium Ylides from Aryl Diazoesters: Their Application in the Synthesis of Diverse Dihydroindolizine
作者:Saibal Sar、Souvik Guha、Tejas Prabakar、Debajit Maiti、Subhabrata Sen
DOI:10.1021/acs.joc.1c01209
日期:2021.9.3
1/2, aryl diazoesters 3, and acrylic ester/3-alkenyl oxindoles 5/6 provide various dihydroindolizines 7 to 9 in excellent yield. The principle of the strategy is photolytic generation of nitrogen ylidesfrom N-heteroarenes and aryl diazoesters and their subsequent [3 + 2] cycloaddition reaction with dipolarophiles. Detailed mechanistic analysis of the transformation through control experiments establishes
An efficient copper-catalyzedcarbenoidinsertion reaction of α-diazo carbonyl compounds into Si–H and S–H bonds was developed. A wide range of α-silylesters and α-thioesters was obtained in high yields (up to 98%) from α-diazoesters using 5 mol% of a simple copper(I) salt as catalyst. Using 0.05 mol% of the same catalyst, α-diazoketones led to α-silylketones in low to good yields (up to 70%).
Iron-Catalyzed Carbene Insertion Reactions of α-Diazoesters into Si–H Bonds
作者:Hoda Keipour、Thierry Ollevier
DOI:10.1021/acs.orglett.7b02488
日期:2017.11.3
An efficient iron-catalyzed carbene insertion reaction of α-diazo carbonyl compounds into the Si–H bond was developed. A wide range of α-silylesters was obtained in high yields (up to 99%) from α-diazoesters using a simple iron(II) salt as catalyst.