Trifluoroacetic acid → HCID 88823815, compound

Participants

Reaction Steps

t-Butyl (6R,7S)-3-acetoxymethyl-7-methoxy-7-[2-triphenylmethoxyimino-2-(fur-2-yl)-acetamido]-ceph-3-em-4-carboxylate (syn isomer) (713.3 mg, 0.966 mmole) was treated with trifluoroacetic acid (10 ml) and anisole (5 ml) for a total of 40 mins. and then added slowly to rapidly stirred saturated aqueous sodium bicarbonate (600 ml.). The mixture was extracted with ethyl acetate (2×150 ml), covered with ethyl acetate (200 ml), and adjusted to pH 2 with orthophosphoric acid. The organic layer was combined with the ethyl acetate wash (200 ml) of the aqueous layer, dried, and evaporated to a brown foam. Chromatography on three 40 × 20 cm. preparative-layer plates in chloroform-methanol-formic acid (90:16:2) provided a sample of the title compound as a pale-yellow foam containing ca 21/2 mole-equivalents water (i.r. and microanalysis) (137 mg, 0.283 mmole, 29%) paper chromatography Rf 0.26, Rf/Rf cephaloram 0.58, λmax (pH 6 buffer) 272.5 nm (ε 16,400).

Provenance & Evidence