2-Hydroxy-4,6-dimethoxydeoxybenzoin was synthesized from 1,3,5- trimethoxybenzene,via the Houben-Hoesch reaction or Friedel-Crafts reaction and demethylation of 2,4,6trimethoxydeoxybenzoin. Because of the protection of methyl group, the reactivity of hydroxy groups was reduced and the yields of Houben-Hoesch and Friedel-Crafts reaction reached to 81.3％ and 94.5％ respectively. The yield of demethylation was 93.8％. The effects of catalyst amount and reaction temperature were investigated, and the optimal process parameters were as follows: (1) in Friedel-Crafts reaction, the ratio of catalyst ( aluminum chloride ) and 1,3,5-trimethoxybenzene 1.1: 1,reaction temperature 25 ℃, (2) in demethylation, the ratio of demethylation reagent and 2,4,6trimethoxydeoxybenzoin 1.2: 1, reaction temperature 82 ℃. The product was characterized with 1H NMR and MS.%以1,3,5-三甲氧基苯为原料,经Houben-Hoesch反应或Friedel-Crafts酰化反应得到2,4,6-三甲氧基脱氧安息香后选择性脱去2位甲基,得到2-羟基-4,6-二氧基脱氧安息香目标产品.因甲基的保护作用降低了羟基的反应活性,使Houben-Hoesch反应单步收率提高到81.3%,Fdedel-Crafts酰化反应收率达94.5%,脱甲基反应收率达93.8%.考察了催化剂用量、温度等因素的影响,优化选择了各反应的较佳工艺参数.Friedel-Crafts酰基化反应中,催化剂AlCl<,3>与1,3,5-三甲氧基苯的摩尔配比1.1:1,反应温度25℃(室温);脱甲基反应中,脱甲基试剂与2,4,6-三甲氧基脱氧安息香的摩尔配比1.2:1,反应温度82℃.产品经<'1>HNMR、MS进行了结构表征.
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