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4 - tert-butylcyclohexyl chloroformate is an important organic intermediates, widely used in the synthesis of pesticides, pharmaceuticals, perfumes, initiator like chemical reagents, especially as the synthesis of novel initiator peroxydicarbonate (4 - tert -butyl ester) of dicyclohexyl direct materials. Conventional Synthesis of 4 - tert-butyl-cyclohexyl chloroformate method of phosgene as a raw material synthesis. The phosgene chemical properties lively, widely used in polyurethane, pesticides, pharmaceuticals, paints, dyes, triggering agent synthesis. However, phosgene as a toxic gas, and accompanied by very corrosive, very prone to leak, resulting in personal injury, thus demanding process conditions. In recent years, green chemistry as one of the most important subjects of today's scientific and technological development, more and more by the attention at home and abroad. Therefore, we have to choose a safe, environmentally friendly the phosgenation reagents alternative phosgene. Solid phosgene as a green raw material for new phosgenation the phosgene reaction, not only to meet, but also avoid the evils of phosgene. The purpose of this study is the use of solid phosgene in place of phosgene, Process for the synthesis of 4 - tert-butyl-cyclohexyl chloroformate ester. Mainly on the reaction time, reaction temperature, reactant ratio, reaction of the reaction effect of the solvent and the catalyst and other factors. Which summed up better process conditions: at room temperature, 4 - tert-butyl-cyclohexyl gliadin in petroleum ether solution, followed BTC petroleum ether solution was slowly added dropwise to the above solution, and dissolved completely, and then at 60 - The 65 ℃ next heated to reflux for 4 hours to complete the reaction. Processing: the first portion of the solvent was distilled off, and low temperature (-5 ° C), the unreacted BTC and 4 - tert-butyl-cyclohexanol, crystallized out, was separated by filtration, the mother liquor using means of purification column. Found in the synthesis of a quick TLC monitoring methods, to find a more convenient way to monitor the reaction. In the discussion of solid phosgene, and 4 - tert-butyl-ring hexyl alcohol of the reaction mechanism, the focus zeolite catalyst reaction mechanism, and 4 - tert-butyl-cyclohexanol and BTC of the reaction mechanism, to establish a 4 - tert-butyl-ring hexyl alcohol itself since catalytic the basis of the reaction. Small scale in the laboratory based on experimental middle of trial - try to enlarge the study. On the basis of considering the characteristics of raw materials and process requirements, we have designed a set of devices suitable for industrial and optimization experiments to solve a series of problems emerged in the amplification experiments, a preliminary study to achieve its industrialization .
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