A novel reaction of α-haloketone (α-bromo and α-chloro ketone) with irradiation under microwave gave the corresponding α-hydroxyketone and pyrazine derivative in good yields. In the case of α,α′-dibromo ketone, α-diketone was obtained. This reaction affords a new, clean and convenient synthetic method for α-hydroxyketone, α-diketone, α-chloro ketone and pyrazine derivative.
Boronic Acid-Catalyzed Selective Oxidation of 1,2-Diols to α-Hydroxy Ketones in Water
作者:Julius M. William、Masami Kuriyama、Osamu Onomura
DOI:10.1002/adsc.201300961
日期:2014.3.24
2‐diols to their corresponding α‐hydroxy ketones in aqueous medium. The oxidation step was accomplished using dibromoisocyanuricacid (DBI) as a terminal chemical oxidant or an electrochemical process. The electrochemical process was based on the use of platinum electrodes, methylboronic acid [MeB(OH)2] as a catalyst and bromide ion as a mediator. Electro‐generated OH− ions (EGB) at the cathode acted
Catalytic Intermolecular Coupling of Rhodacyclopentanones with Alcohols Enabled by Dual Directing Strategy
作者:Ya-Lin Zhang、Rui-Ting Guo、Jia-Hao He、Xiao-Chen Wang
DOI:10.1021/acs.orglett.9b01420
日期:2019.6.7
A catalytic carbonylative ring-opening and functionalization reaction of poorly activated cyclopropanes has been developed. The key achievement of this work is the accomplishment of an unprecedented effective intermolecular trapping of the rhodacyclopentanone intermediate, which is derived from rhodium-mediated carbonylative insertion of poorly activated cyclopropanes, by an external reactant. The
Cyclic Seleninate Esters as Catalysts for the Oxidation of Sulfides to Sulfoxides, Epoxidation of Alkenes, and Conversion of Enamines to α-Hydroxyketones
作者:Eric A. Mercier、Chris D. Smith、Masood Parvez、Thomas G. Back
DOI:10.1021/jo300313v
日期:2012.4.6
sulfides to sulfoxides, alkenes to epoxides, and enamines to α-hydroxyketones. Optimal conditions were found that minimize the overoxidation of the product sulfoxides to sulfones and the hydrolysis of epoxides to diols. In some examples such as styrene derivatives, oxidative cleavage was observed instead of epoxidation. The enamine oxidations proceed via the initial formation of dimeric 2,5-diamino-1
Ynolates were found to react with alpha-alkoxy-, alpha-siloxy-, and alpha-aryloxyketones at room temperature to afford tetrasubstituted olefins with high Z selectivity. Since the geometrical selectivity was determined in the ring opening of the beta-lactone enolate intermediates, the torquoselectivity was controlled by the ethereal oxygen atoms. From experimental and theoretical studies, the high Z