Reaction #73575

Reaction equation

metformin hydrochloride

sodium hydroxide

acetic acid

→

metformin acetate

Yield 48.7%

Solvents

water

Conditions

Workup

1. 1
   workup.STIRRINGthe mixture was stirred overnight at room temperature
2. 2
   WashThe resulting crystal was washed with acetone-water (12:1) mixture
3. 3
   Dryingacetone, and dried at 60° C.

Procedure

5 L of water, 2 kg (1 equivalent) of metformin hydrochloride and 578 g (1.2 equivalents) of sodium hydroxide were added to 10 L reactor, and stirred for 2 hours at room temperature. Then 1 L (1.45 equivalents) of acetic acid was added for 1 hour, and the mixture was stirred overnight at room temperature. The resulting crystal was washed with acetone-water (12:1) mixture, and then acetone, and dried at 60° C. to obtain 1,112 g of metformin acetate (yield: 48.7%).

Source