Synthesis Of 2-methoxy-4-methyl Phenol

Vanillin(3-methoxy-4-hydroxybenzaldehyde),a broad-spectrum spice,can be widely used in cosmetics,daily chemicals,food and beverage industry.This paper focuses on the research status of 2-bromo-4-methyl phenol and methanol synthesis sodium methyl guaiacol.We had a review of the literature on the alkoxylation reaction and some halogenated aromatic compounds dehalogenation first.Then we are using a cuprous chloride,anhydrous copper sulfate,copper oxide,basic copper carbonate and other monovalent or divalent copper salt as a catalyst.We select DMF,CO2,methyl formate,DMSO,pyridine,picoline,sodium carbonate,urea(carbamide)and other 8 as a secondary reagent catalyst.We also had studied how temperature,feed ratio,and reaction time affect the yield of methoxylated.According to the results,we had got the best reaction conditions.At atmospheric pressure,the system external temperature 90 ?,O-bromophenol with sodium methoxide molar ratio of 1: 3.4,using DMF as co-catalyst,o-bromo-p-cresol conversion rate reached 99%,yield 94%;using CO2 as co-catalyst,o-bromo-p-cresol conversion rate reached 98%,yield 92%;methyl formate as co-catalyst,the conversion of o-bromo-p-cresol was 100%,yield 90%.From the research results,the process route has been got through.Through theoretical calculations and production line analysis we found that the costs using p-cresol route should be lower than the theoretical guaiacol routes,and waste emissions significantly lower than guaiacol route.In summary,the p-cresol route should be a promising process route to replace the guaiacol route,and be worthy of further study.