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Important pharmaceuticals, pesticides and resin intermediates 4 ( 5 ) - (hydroxymethyl) imidazole synthesis process on the basis of the previous literature . 1,3 - dihydroxyacetone and formamidine acetate as raw materials and as raw material 4,5 - di - carboxylic acid imidazole Synthesis of 4 (5 ) - (hydroxymethyl) imidazole two process has been studied and optimized , while 4 (5) - a reduction reaction of the carboxylic acid imidazole ethyl exploratory experiment . The preferred process as the raw material of 1,3 - dihydroxy acetone and acetic formamidine : 1,3 - dihydroxyacetone 22.54g (0.25mol), formamidine acetate 29.12g ( 0.28 mol ) , isopropanol 120ml, pass into the liquid ammonia , 40 ℃ reaction 8h, after removal of the ammonia in the reaction solution by distillation under reduced pressure and filtered , the filtrate was added to the hot picric saturated solution , natural cooling to room temperature, 4 (5 ) - (hydroxymethyl) imidazole picrate 69.5g, yield 85.0%. Preferred process as raw material 4,5 - di - carboxylic acid imidazole : 1 ) decarboxylation reaction : 4,5 - dicarboxylic imidazol - 40g, acetic anhydride 1200ml , refluxed for 10h, filtered and the filtrate was concentrated to dryness , the resulting solid was added to 50% ethanol solution was refluxed , filtered and the filtrate was naturally cooled overnight, and filtered to give a solid ; 2) esterification reaction : 4 ( 5 ) - carboxylic acid imidazole of 50g, ethanol 1000ml and 60ml of concentrated sulfuric acid , heated under reflux 2H , 5 % concentration of NaOH . solution was adjusted to pH = 8, and concentrated to dryness under reduced pressure , adding a small amount of water and refluxed overnight and filtered to give a solid , natural cooling ; 3) reduction reaction : of LiAlH 4 10g , ether 300ml and 4 (5 ) - carboxylic acid the imidazole ethyl acrylate 28g, room temperature reaction 1.5h, 25ml of water was added dropwise carefully and then filtered , and the residue was dissolved in 300 ml of methanol and filtered , the the collected ether and methanol filtrate was concentrated to dryness , the resulting solid was dissolved in 300ml of ethanol was heated to reflux , after the solution was concentrated to about 30ml, cooled and filtered to give a solid , the route total yield was 49.6% .
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