Pentylene Glycol

An organic compound, colorless transparent liquid with a relative density of 0.971, soluble in organic solvents such as alcohols, ethers and ethyl acetate. 1,2-Pentanediol is the key raw material for the synthesis of the fungicide propiconazole.

Chinese Name: 1,2-Pentanediol

Chinese synonyms: pentylene glycol, α-n-pentylene glycol, α-n-pentanediol

English names and synonyms:

PENTANE-1,2-DIOL； PTD； pentyleneglycol； 1,2-pentanediol； 1,2-DIHYDROXYPENTANE； 1,2-PENTANEDIOL； 1,2 Pentandiol

CAS：5343-92-0

EINECS：226-285-3

MDL：MFCD00010736

Using 1-pentene, hydrogen peroxide and formic acid as raw materials, the molar ratio is 1:1.5:4. The reaction equilibrium mixture is formed by the following procedure: slowly add 1-pentene and hydrogen peroxide (70%) to formic acid at 40~55 °C at the same time, after addition, stir the mixture at 55 °C for 1 hour, move into the circulation reactor, the reactor has a circulation pump and an overflow siphon, heat to 55 °C and circulate, then add 1-pentene and formic acid, added by one addition tube, hydrogen peroxide is added from another addition tube, at this time an exothermic reaction occurs, and the temperature is allowed to rise to 62~63 °C, These components are added according to a certain proportion and speed, the equilibrium operation is controlled by the circulating constant temperature device, about 8h, the reaction stops, a large amount of 1,2-pentanediol formate is obtained, formic acid and water are removed by vacuum distillation, the residue obtained is added to 25% NaOH solution for hydrolysis, solvent extraction desolubilization distillation is obtained to obtain 1,2-pentanediol, the yield can reach 91%, m p.96~98 °C/1.3kPa.