1-Hydroxycyclohexyl Phenyl Ketone CAS 947-19-3

The specific method of the photoinitiator 184 includes the following steps:

1. Cyclohexanecarbonyl chloride carries out electrophilic substitution reaction with benzene under Lewis acid catalysis to obtain only cyclohexyl phenyl ketone.
2. Cyclohexyl phenyl ketone reacts with hydrogen peroxide and hydrochloric acid solution under the effect of catalyst to obtain 1-chlorocyclohexyl phenyl ketone.
3. The chlorinated intermediate undergoes hydrolysis reaction with aqueous sodium hydroxide solution under the action of a catalyst to obtain 1-hydroxycyclohexyl phenyl ketone.

Utilizing hydrogen chloride in the by-product hydrochloric acid in the process of synthesizing alkyl ketones, in hydrogen peroxide and organic solvent systems, chlorination and hydrolysis are carried out with L potassium molecular sieve catalyst to form α-hydroxy ketones. This new synthesis method has the following advantages: The raw materials are cheap and easy to obtain, safe and environmentally friendly, and the hydrogen chloride generated during the electrophilic substitution reaction of the acid chloride under the catalysis of Lewis acid is fully utilized, and the hydrogen chloride is recycled to reduce the discharge of waste acid water, and is environmentally friendly. The selective chlorination and hydrolysis are completed in the same kettle, the operation is simple, the loss is small, and the yield is high.

A synthesis technique of 1-hydroxycyclohexyl phenyl ketone, which is characterized in that the steps are as follows:

• Acylation: add cyclohexylformic acid into the reaction kettle, heat up to 35±2°C, add phosphorus trichloride, and keep the temperature at 60±2°C for at least 4 hours, then remove the inorganic layer to obtain cyclohexanecarbonyl chloride; , the weight ratio of raw material cyclohexyl formic acid and phosphorus trichloride is 1.8-2.2:1;
• Friedel-Crafts reaction: add benzene and catalyst aluminum trichloride into the reaction kettle, cool down to 5-10 ℃, dropwise add the cyclohexanecarbonyl chloride obtained in step (1), benzene, aluminum trichloride and cyclohexane The weight ratio of hexanoyl chloride is 9:2.9-3.1:3.16-3.36, and the temperature is 15±2°C for at least 2.5 hours to obtain a complex of cyclohexyl phenyl ketone and aluminum trichloride;
• Hydrolysis reaction: add an appropriate amount of dilute hydrochloric acid with a mass concentration of 1.5-2.5% into the complex, stir to separate layers, remove the aqueous layer containing aluminum trichloride, and then add an appropriate amount of water to wash the acid until pH>5 Finish, finally remove unreacted raw material benzene by distillation, obtain cyclohexyl phenyl ketone;
• Chlorination reaction: add cyclohexyl phenyl ketone into the chlorination kettle, heat up to 60±2°C, then feed chlorine gas, and the reaction ends to obtain 1-chlorocyclohexyl phenyl ketone;
• Alkali hydrolysis reaction: add 1-chlorocyclohexyl phenyl ketone into the liquid caustic soda at a weight ratio of 1:0.95-1.10, stir until the reaction ends, then add toluene for extraction, separate the water phase, desolvate, and recover Toluene to obtain crude 1-hydroxycyclohexyl benzophenone;
• Refining: put the crude 1-hydroxycyclohexyl benzophenone into the rectification kettle, rectify the product under the reduced pressure of the Roots pump, and collect the fractions; put the rectified product into the crystallization kettle, and then use The petroleum ether is dissolved and recrystallized, and then centrifuged. The distilled mother liquor is distilled out of the solvent petroleum ether for reuse. After the wet product is dried, the finished product 1-hydroxycyclohexyl benzophenone is obtained.