A mild and environmentally acceptable synthetic protocol for chemoselective α-bromination of β-keto esters and 1,3-diketones
作者:Abu T. Khan、Papori Goswami、Lokman H. Choudhury
DOI:10.1016/j.tetlet.2006.02.075
日期:2006.4
A wide variety of unsubstituted β-keto esters can be brominated chemoselectively to the corresponding α-monobromo-β-keto esters by using a combination of vanadium pentoxide, hydrogen peroxide and ammonium bromide in a biphasic system, dichloromethane–water at 0–5 °C. In addition, α-mono substituted β-keto esters, cyclic β-keto-esters and 1,3-diketones can also be brominated selectively using the same
在双相系统中,五氧化二钒,过氧化氢和溴化铵结合使用,二氯甲烷-水在0–5°时,可以将多种未取代的β-酮酯化学选择性地溴化为相应的α-单溴-β-酮酯C。另外,α-单取代的β-酮酯,环状β-酮酯和1,3-二酮也可以使用相同的方案选择性地溴化。