双酚A溴化过程中的溶剂效应

以脂肪醇-水、氯苯、乙酸、环己烷、硝基苯、氯苯-醇、环己烷-醇为溶剂,采用溴素/双氧水原位溴化-氧化法合成了四溴双酚A.考察了不同溶剂对产品收率、纯度、操作工艺的影响.结果表明,弱极性的环己烷对双酚A的溶解性不佳,不适于作为合成四溴双酚A的溶剂;而环己烷-脂肪醇混合溶剂,由于加大了溶剂的极性使溴化反应成为可能;乙酸、脂肪醇、硝基苯、氯苯、氯苯-脂肪醇为极性溶剂,可加速反应,是合成四溴双酚A的良好溶剂,其中氯苯-脂肪醇混合溶剂,可避免以纯氯苯为溶剂时的碱洗、水洗操作,从而大大简化合成工艺,从工业化的角度看是很好的选择.

The effect of the organic solvents on the synthesis of tetrabromobisphenol-A

Tetrabromobisphenol-A was synthesized with fatty alcohols-water,chlorobenzene,acetic acid,cyclohexane,nitrobenzene,chlorobenzene-fatty alcohols,and cyclohexane-fatty alcohols as solvents from bisphenol-A,bromine and hydrogen peroxide by in-situ bromination-oxidation.The effect of the solvents on the yield,the content of the production and the process were studied in detail.It showed that cyclohexane was not a suitable solvent for the synthesis of the tetrabromobisphenol-A,since it was not able to dissolve the bisphenol-A for its weak polarity,but the bromination was realized when mixed the cyclohexane with the fatty alcohols for increasing the polarity of the solvent;while acetic acid,fatty alcohols-water,nitrobenzene,chlorobenzene,chlorobenzene mixed with fatty alcohols were all good solvents for the synthesis of the tetrabromobisphenol-A,for they were all polar solvents and can quicken the reaction.Especially,the steps of washing with the sodium sulfite and water when with chlorobenzene as the solvent were avoided when with chlorobenzene mixed with fatty alcohols as the solvent,as a result,the process of the synthesis was reduced greatly,and the time and resource were economized.