Rhodium-catalyzed synthesis of 2,3-diaryl-1,4-diketones via oxidative coupling of benzyl ketones using α-thioketone oxidizing reagent
作者:Mieko Arisawa、Guangzhe Li、Masahiko Yamaguchi
DOI:10.1016/j.tetlet.2012.12.107
日期:2013.3
no)benzene (dppBz) catalyzed the oxidativecoupling reaction of aryl benzyl ketones giving 2,3-diaryl-1,4-diketones in high yields. 3,3-Dimethyl-1-methylthio-2-butanone was used as the oxidizing reagent, which was converted to 3,3-dimethyl-2-butanone and dimethyl disulfide. Rhodium enolates were catalytically formed from ketones, which underwent oxidativecoupling using an organosulfur reagent.
Aldehyde Termination: A novel copper‐catalyzed transformation from methylketones into aldehydes has been accomplished. This method is applicable to a wide range of aromatic and aliphatic methylketones and chemoselectively produces aldehydes, accompanied by the release of hydrogen (H2) and carbon dioxide (CO2) as by‐products.
Cu(OAc)2, and dioxygen in molten tetrabutylammonium acetate (TBAA) promotes an unusual cyclopropanation reaction between arylmethylketones and styrenes. The process is a dehydrogenative cyclizing coupling that involves a twofold CH activation at the α‐position of the ketone. The substrate scope highlights the flexibility of the catalyst; a reaction mechanism is also proposed.
The reaction of carbanions with 2-substituted-2-nitropropanes
作者:Glen A. Russell、Boguslaw Mudryk、Francisco Ros、Mikolaj Jawdosiuk
DOI:10.1016/0040-4020(82)80123-3
日期:1982.1
The reaction of mono-enolate anions with O2NCMe2X where X = Cl, NO2, p-MePhSO2 yield coupling (RCOCH(R′)(CMe2NO2) and enolate dimerization products (RCOCH(R′)CH(R′)COR) by free radical chain mechanisms involving bimolecular substitution or electrontransferreactions between the enolate anion and the intermediate nitro alkane radical anion (XCMe2NO2−).
单烯酸根阴离子与X = Cl,NO 2,p -MePhSO 2的O 2 NCMe 2 X反应产生偶联(RCOCH(R')(CMe 2 NO 2)和烯醇二聚产物(RCOCH(R')CH (R')COR)通过涉及烯醇阴离子和中间体硝基烷烃自由基阴离子之间的双分子取代或电子转移反应的自由基链机构(XCMe 2 NO 2 - )。
Copper-catalyzed base-accelerated direct oxidation of C–H bond to synthesize benzils, isatins, and quinoxalines with molecular oxygen as terminal oxidant
作者:Jing-Wen Yu、Shuai Mao、Yong-Qiang Wang
DOI:10.1016/j.tetlet.2015.02.019
日期:2015.3
an efficient one-pot procedure for the synthesis of quinoxaline derivatives was realized. The two protocols feature using molecular oxygen as terminal oxidant, low catalyst loading, wide substrate scope, and highfunctional-grouptolerance.