摘要
在氢氧化钾作用下,加入少量的相转移剂,2,4-二羟基二苯甲酮与1-溴代正辛烷反应可制备紫外线吸收剂2-羟基-4-正辛氧基二苯甲酮。通过向反应体系中加入少量水溶性的有机溶剂可明显改善产品质量。实验结果表明,二甲基亚砜的效果较好。重点考察了各类表面活性剂对该反应的影响。这些表面活性剂包括甲基硫酸十八烷基三甲基铵、氯化二甲基双十六烷基铵、氯化烷基三甲基铵、十二烷基苯磺酸铵、十八烷基甲基磺酸钠,同时还考察了工业乳化剂和聚乙二醇对该反应的影响。实验发现氯化二甲基双十六烷基铵的用量为0.8％(基于水的质量分数)时,2-羟基-4-正辛氧基二苯甲酮的纯度可达到88.5％,产品的分离产率为93.2％,外观为淡黄色。氯化二甲基双十六烷基铵是一种比较理想的相转移剂。
Under the reaction of KOH, adding a little bit of phase transfer agent, the ultra - violet absorbant 2-Hydroxy-4-n-octaoxybenzophenones can be prepared by the reacting of 2,4-dihydroxybenzophenone with 1-bromooctane. The quality of this product can be improved significantly by adding some water - soluble organic solvent into the reaction system. Experiment shows that dimethyl sulfoxide gives better results. The influences of various surfactants on this reaction are emphatically investigated. These surfactants are methyl sulfate octadecyltrimethylbenzylammonium, dihexadecyldimethylammonium chloride, include:chloro - alkyl trimethyl ammonium, ammonium dodecyl benzene sulfonate, sodium octadecylmethyl sulfate. The effects of some industrial emulsifiers and polyethylene glycol (PEG) on this reaction are studied, It is found by experiment that the purity and yield of 2-hydroxy-4-n-octaoxybenzophenones reach 88.5% and 93.2% respectively by adding 0.8% dihexadecyldimethylammonium chloride (by weight of water) into the reaction mixture. The color of product is yellow. Dihexadecyldimethylammonium chloride is an ideal phase transfer agent.
出处
《当代化工》
CAS
2003年第1期20-22,共3页
Contemporary Chemical Industry
