The synthesis of aromatic ketones by chromium-catalyzed Kumada arylation of secondary amides with organomagnesium reagents is described. This reaction was enabled by using low-cost chromium(III) salt as a precatalyst, combined with trimethylsilyl chloride as an additive, and presents a rare example of catalytic transformation of secondary amides to ketones at room temperature. It was shown that catalytically
anhydrides to zerovalent palladium complexes to yield acyl(carboxylato)bis(tertiary phosphine)palladium(II) complexes and their reactions with organoboronic acids to yield ketones, a novel catalytic process has been developed. This converts carboxylic anhydrides and organoboroncompounds into ketones catalyzed by palladium complexes under mild conditions. The process provides a general, versatile, synthetic
在对羧酸酐与零价钯配合物氧化加成生成酰基(羧基)双(叔膦)钯 (II) 配合物及其与有机硼酸反应生成酮的基础研究的基础上,开发了一种新的催化工艺。这在温和条件下将羧酸酐和有机硼化合物转化为由钯配合物催化的酮。该方法提供了一种通用的、通用的合成方法来生产具有芳香族、脂肪族和杂环基团的各种对称和不对称酮。建议催化循环包括(a)羧酸酐的氧化加成以产生酰基(羧基)钯中间体,(b)与有机硼化合物进行金属转移以产生酰基(有机)钯中间体,(c) 还原消除生成酮。发现不仅均相催化剂体系而且非均相体系在温和条件下产生酮。
Carbonylative Suzuki Couplings of Aryl Bromides with Boronic Acid Derivatives under Base-Free Conditions
作者:Klaus M. Bjerglund、Troels Skrydstrup、Gary A. Molander
DOI:10.1021/ol5003362
日期:2014.4.4
The carbonylative Suzuki-Miyaura reaction between aryl bromides and arylboronic acid equivalents is herein reported, using base-free conditions and a limited excess of carbon monoxide generated ex situ from stable CO. precursors. Under these conditions, unsymmetrical biaryl ketones were obtained in modest to excellent yields. This method was adapted to the synthesis of the triglyceride and cholesterol regulator drug, fenofibrate, and its C-13-labeled derivative in good yields from the appropriate CO-precursor.
The Pinacol—Pinacolone Rearrangement. VI. The Rearrangement of Symmetrical Aromatic Pinacols
作者:W. E. Bachmann、James W. Ferguson
DOI:10.1021/ja01325a023
日期:1934.10
Synthesis of Terminal Allenes through Copper-Mediated Cross-Coupling of Ethyne with<i>N</i>-Tosylhydrazones or α-Diazoesters
作者:Fei Ye、Chengpeng Wang、Xiaoshen Ma、Mohammad Lokman Hossain、Ying Xia、Yan Zhang、Jianbo Wang
DOI:10.1021/jo502316q
日期:2015.1.2
Ethyne is employed as coupling partner in copper-mediated cross-coupling reactions with N-tosylhydrazones and alpha-diazoacetate, leading to the development of a new synthetic method for terminal allenes. With this novel coupling method, the terminal allenes were obtained in good yields and with excellent functional group tolerance. Copper carbene migratory insertion is proposed as the key step in these transformations.