Sodium Hydroxide → Zoledronate disodium tetrahydrate

Participants

Reaction Conditions

Reaction Steps

A 0.5 liter reactor equipped with a mechanical stirrer, a thermometer, a reflux condenser and a dropping funnel, was loaded with Zoledronic acid form I (10.0 g) and water (130 ml). The suspension was heated to reflux temperature to obtain a clear solution. A 40% aqueous solution of Sodium hydroxide (6.9 g) was added drop-wise. The solution was then cooled to 4° C. during 2 hours and was stirred at this temperature for about 1.5 hours. The solution was concentrated to half of its volume to obtain a precipitate. The white precipitate was filtered and dried in a vacuum oven at 50° C. for 22 hours to obtain 2.7 g (22%) of Zoledronate disodium crystal form VII (LOD by TGA=10.7%).

Provenance & Evidence