Preparation of procaine & procaine hcl

Procaine base

CAS: 59-46-1

Appearance: white crystalline powder

Melting point (boiling point): 59 ~ 62 ℃

Molecular formula: c13h2on2o2

Molecular weight: 236.31

Procaine hcl

CAS: 51-05-8

In a 250ml three necked flask with stirrer and thermometer, nitrocaine solution with pH of 4.0-4.2 is added. Under full stirring, activated iron powder is added at 25 ℃ in several times. After adding, the reaction temperature rises automatically and maintains 40-45 ℃. The reaction time was 2 hours. After filtration, the filter residue is washed twice with a small amount of water, the washing solution is combined with the filtrate, acidified to pH 5 with dilute hydrochloric acid (10%), and the saturated sodium sulfide solution is added to pH 7.8-8.0 to precipitate the iron salt in the reaction solution. The filtrate is acidified to ph6 with a small amount of dilute hydrochloric acid, and then heated at 50-60 ℃ for 10 minutes with a small amount of activated carbon. The filter residue is washed once with a small amount of water, the washing solution is combined with the filtrate, cooled to below 10 ℃, and alkalized with 20% NaOH until procaine is completely separated (pH 9.5-10.5). Filter, wash twice, press and drain for salt forming(procaine hcl)