Ethanol → Potassium Clavulanate

Participants

Reaction Steps

Lithium clavulanate (5.15 g, estimated purity 95% pfa; 0.025 moles) was dissolved in water (45 mls) and cooled in an ice bath. Tripotassium orthophosphate (10.1 mls of 1 M solution; 1.2 equivalents) was added in one lot. Ethanol (32 mls) was added slowly over 1/2 hour by which time lithium phosphate had precipitated out and the pH had fallen from 8.3 to 7.3. The mixture was then made up to 800 mls with acetone over 3/4 hr. Celite (2 gm) was added and then the mixture was filtered to give a clear, colourless filtrate. This was added with rapid stirring to acetone (1750 mls) over 1 hr and the white solid was filtered off, washed with acetone (3×50 mls) and dried on a fluid bed dryer to yield potassium clavulanate (4.8 g, 82.9 pfa, 81% recovery).

Provenance & Evidence