Room-Temperature Coupling/Decarboxylation Reaction of α-Oxocarboxylates with α-Bromoketones: Solvent-Controlled Regioselectivity for 1,2- and 1,3-Diketones
作者:Zhen He、Xiaotian Qi、Zhijie She、Yinsong Zhao、Shiqing Li、Junbin Tang、Ge Gao、Yu Lan、Jingsong You
DOI:10.1021/acs.joc.6b02575
日期:2017.2.3
A transition-metal-free and room-temperature coupling/decarboxylation reaction between α-oxocarboxylates and α-bromoketones is reported herein. It represents the first mild and regioselective synthesis of either 1,2- or 1,3-diketones from the same starting materials. Notably, the regioselectivity is simply controlled by solvents. The preliminary experimental data and DFT calculations suggest sequential
<i>Te</i>-1-Acylmethyl and <i>Te</i>-1-Iminoalkyl Telluroesters: Synthesis and Thermolysis Leading to 1,3-Diketones and <i>O</i>-Alkenyl and <i>O</i>-Imino Esters
A series of Te-1-acylmethyl carbotelluroates was prepared in good isolated yields from the reaction of potassium carbotelluroates with -haloketones in acetonitrile. Thermolysis of the telluroesters afforded vinyl esters in 20-50% yields, while treatment of the carbotellurorates with potassium t-butanolate led to 1,3-diketones in 30-75% yields with the liberation of black tellurium. The reaction of potassium carbotelluroates with -haloaceto oximes gave O-acyl oximes in 50-70% yields via Te-1-iminomethylcarbotelluroates.
Synthesis of 1,3-Diketones by Reaction of<i>α</i>-Haloketones with Acyl Cyanides Promoted by Samarium Diiodide
作者:Heung Soo Baek、Byung Woo Yoo、Sam Rok Keum、Cheol Min Yoon、Sung Hoon Kim、Joong Hyup Kim
DOI:10.1080/00397910008087289
日期:2000.1
Abstract α-Haloketones reacted with acyl cyanides to form 1,3-diketones in the presence of samariumdiiodide. The reaction was assumed to proceed via a mechanism involving samarium enolates formed in situ from α-haloketones.
PPh3-catalyzed β-selective addition of α-fluoro β-dicarbonyl compounds to allenoates
作者:Yong-Liang Liu、Xiao-Ping Wang、Jie Wei、Ya Li
DOI:10.1016/j.tet.2021.132577
日期:2022.1
A highly selective phosphine-catalyzed β-addition of α-fluoro β-dicarbonylcompounds to allenoates has been developed. Both α-fluoro β-diketones and α-fluoro β-keto esters prove to be competent fluorocarbon nucleophiles, giving a series of the β-addition products bearing a fluorinated quaternary carbon center in good to excellent yields and with excellent regioselectivities. A plausible reaction pathway