Sodium Hydroxide → Ibandronate Sodium Anhydrous

Participants

Reaction Steps

A solution of sodium hydroxide (0.58 g) in water:acetone (20:80 v/v, 9 ml) was added dropwise to a solution of amorphous ibandronic acid (5 g) in water:acetone (20:80 v/v, 49 ml) at reflux temperature. The reaction mixture was heated at reflux temperature for an additional 1.5 hours to obtain a pH of 4.0. Then the reaction mixture was cooled to room temperature. Further cooling was performed using an ice-bath. The precipitate was filtered, washed with acetone (1×50 ml), and dried in a vacuum oven at 50° C. for 21 hours to give 3.8 g of ibandronate sodium crystal form T. Form T can exhibit a weight loss of about 5% and about 7% in TGA.

Provenance & Evidence