Lithium fluoride → Potassium Clavulanate

Lithium clavulanate (7.15 g, estimated purity 68% pfa 0.025 moles) was stirred in water (45 mls) and cooled in ice. Potassium fluoride solution (3.5 g KF.2H2O in 9 mls solution; 1.5 equivalents) was added slowly to the cloudy brown solution and lithium fluoride separated out as a fairly gummy deposit. The mixture was made up to 100 ml with acetone over 3/4hr and then up to 800 mls with acetone over 1/2 hr. The solid which had separated now was dark brown and was removed by filtration through celite (4 gm). The almost colourless filtrate was added to acetone (1750 ml) over 1 hr with rapid agitation, then filtered and washed with acetone (3×50 ml) and fluid bed dried to give a fine granular just off-white solid potassium clavulanate (3.6 g, 83.1% pfa, 62% recovery).

1. temperaturecooled in ice
2. customseparated out as a fairly gummy deposit
3. waitThe mixture was made up to 100 ml with acetone over 3/4hr
4. customThe solid which had separated now was dark brown
5. customwas removed by filtration through celite (4 gm)
6. additionThe almost colourless filtrate was added to acetone (1750 ml) over 1 hr with rapid agitation
7. filtrationfiltered
8. washwashed with acetone (3×50 ml) and fluid bed
9. customdried

ORD record

ord-5a61272768264719a1a123a8b1ca1acc

Source dataset

uspto-grants-1981_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04255332