Triethylamine → Phthalide

Participants

Reaction Steps

A solution of 6-tritylaminopenicillanic acid (9.8 g; 0.02M) in dry acetone (100 ml) was cooled to 0° C, triethylamine (2.9 mg, 0.02 M) was added, followed by 3-bromophthalide (4.1 g; 0.02M) in dry acetone (20 ml.), and the reaction mixture kept at 0° C with stirring for 2 hours and finally at ambient temperatures for 1 hour. The triethylammonium bromide which precipitated was removed by filtration, the evaporated filtrate was dissolved in ethyl acetate (150 ml) and after two washings with cold 2% aqueous sodium bicarbonate (2 × 150 ml) and with ice-water (2 × 100 ml) the ethyl acetate layer was dried over anhydrous magnesium sulphate to yield, on removal of solvent in vacuo, phthalide 6-tritylaminopenicillanate as a white amorphous solid.

Provenance & Evidence