2,2,6,6-四甲基-3,5-庚二酮的批量制备

Batch preparation of 2,2,6,6-tetramethylheptanedionate

以氢化钠为缩合剂,3,3-二甲基丁酮(PC)和二甲基丙酸甲酯(MP)为原料,制备2,2,6,6-四甲基-3,5-庚二酮。小量制备最佳条件为:n(PC)∶n(MP)∶n(NaH)=1∶1.48∶3.0,酮滴加时间为4 h,回流时间6 h。在此基础上进行扩大化生产,并对生产条件进一步优化:n(PC)∶n(MP)∶n(NaH)=1∶1.48∶1.81,酮滴加为7 h,回流时间为14 h,产率达82.11%,高于文献报道的最高产率72%。

Using sodium hydride as condensing agent, the 2,2,6,6-tetramethyl-3,5-heptanedione was pre- pared from pinacolone and methyl pivalate. Through small experiments, the preliminary optimize reaction condition was as follows：n（PC）： n（ MP）： n（Nail） = 1 ： 1.48： 3.0, the dropping time of pinacolone 4 h and refluxing time 6 h. Based on those, expanded production and further optimized the reaction condition： n （ PC ）： n （ MP）： n （Nail） = 1 ： 1.48 ： 1.81, the dropping time of pinacolone 7 h, refluxing time 14 h, with yield of 82.11%,higher than the yield reported in literature 72%.