N-Bromosaccharin/$Mg(ClO_4)_2$ is an effective and regioselective system for $\alpha}$-monobromination of 1,3-dicarbonyl compounds. A wide variety of $\beta}$-keto esters and 1,3-diketones in reaction with this system afforded a regioselectively $\alpha}$-monobrominated products. The bromination reaction can be conducted at 0-5 $^\circ}C$ either in solution or under solvent-free conditions.
The Base-induced Reactions of 2-Halogeno-1,3-diketones in a Variety of Solvents
作者:Tadahiro Wakui、Yoshio Otsuji、Eiji Imoto
DOI:10.1246/bcsj.47.1522
日期:1974.6
The reactions of 2-bromo-2-methyldimedone (1), 2,2-dibromodimedone (6), 2-bromo- and 2-chloro-2-methylcyclohexane-1,3-dione (10a and 10b) and 2-acetyl-2,6-dibromocyclohexanone (14) with an equivalent of sodium acetate in a variety of solvents were studied. The constitutions and proportions of the products obtained by these reactions depended strongly on the structure of 2-halogeno-1,3-diketones and