2,2-二甲基-3-氯丙醇(简称LBC)是1,2-转位重排法生产布洛芬过程中产生的副产物。采用卤代醇皂化水解路线将LBC转化成新戊二醇,能够提高布洛芬生产工艺的原子经济性,降低生产成本,但目前LBC皂化反应收率较低。对LBC皂化反应开展研究,通过单因素实验探究了相转移催化剂(PTC)浓度、反应初始压力、温度、碱浓度、原料配比(氢氧化钠与LBC摩尔比)对目标产物2,2-二甲基-1,3-环氧丙烷(简称HBM)收率的影响规律,在优化条件下HBM收率达到94.47%。首次使用气质联用技术(GC-MS)对副反应产物进行研究,发现有甲醇、甲酸钠和异丁烯等副产物生成。根据副产物推断副反应路径如下:LBC首先生成一氯甲醇与异丁烯,然后一氯甲醇与氢氧化钠反应生成甲醛和氯化钠,甲醛在碱性条件下继续发生Cannizzaro反应最终生成甲醇和甲酸钠。

2,2-Dimethyl-3-chloropropanol (LBC) is a by-product in the production of ibuprofen through 1,2-migration rearrangement method.LBC is converted into neopentyl glycol via halohydrin saponification hydrolysis route,which can effectively solve environmental problems,improve atomic economy and reduce production cost of ibuprofen.However,the yield of LBC saponification reaction is low.LBC saponification reaction of ibuprofen production process is studied,and the influences of the concentration of phase transfer catalyst (PTC),initial pressure,temperature,the concentration of alkali and the molar ratio of sodium hydroxide to LBC on the yield of 2,2-dimethyl-1,3-epoxypropane (HBM),the target product,are investigated by means of single factor experiments.The yield of HBM reaches 94.47% under the optimized conditions.GC-MS is used to study the products of side reactions for the first time,and it is found that by-products such as methanol,sodium formate and isobutylene are generated.According to the by-products,the side reaction mechanism is deduced as follows:LBC firstly generates monochloromethanol and isobutylene,and then monochloromethanol reacts with sodium hydroxide to form formaldehyde and sodium chloride,finally formaldehyde continues to undergo Cannizzaro reaction under alkaline conditions to form methanol and sodium formate.