p-Toluenesulfonic acid → HCID 131710049, compound

Participants

Reaction Steps

t-Butyl 3-p-fluorobenzyl-7-triphenylmethylamino-3-cephem-4-carboxylate (IX) (72 mg) was dissolved in acetone and the solution cooled to 0°. p-Toluene sulphonic acid (25 mg) in acetone (0.5 ml) was added dropwise over a few minutes and the solution left to warm to room temperature with stirring. After 2.5 hours a solid had formed but t.l.c. still showed some unchanged (IX) to be present. The mixture was again cooled to 0° and a further quantity of p-toluene sulphonic acid (5 mg) in acetone added. After leaving at room temperature for a further 1.5 hours, the white solid was filtered off. This solid was suspended in ethyl acetate and treated with saturated sodium bicarbonate solution. The organic layer was washed with brine, dried and evaporated to give t-butyl 7-amino-3-p-fluorobenzyl-3-cephem-4-carboxylate (XI) (28 mg) shown to be pure by t.l.c. ##SPC17##

Provenance & Evidence