Trifluoroacetic acid → HCID 57979480, compound

Participants

Reaction Steps

2-Amino-6-(methoxycarbonyl) benzoic acid (1) was made from 3-nitrophthalic acid using the procedure first reported by Rogers and Averill (Rodgers, M. E. and Averill, B. A., J. Org. Chem., 1986, 51, 3308) and then used immediately to make Diels Alder cycloadduct 2 via the 3-(methoxhycarbonyl)dehydrobenzene intermediate that is generated under aprotic diazotization reaction conditions (based on modified conditions first reported by Giles, R. G. F., Sargent, M. V., and Sianipar, H., J. Chem. Soc. Perkin Trans I, 1991, 1571). Treatment of cycloadduct 2 with TFA in refluxing methanol yielded a 1:2 mixture of regioisomeric naphthols 3a and 3b which were separated by column chromatography on silica gel. The 1,5-naphthol regioisomer (3a) was then reduced with LAH to produce 5-hydroxymethyl naphthol 4, which was then coupled to carbapenem intermediate 5 (CPI 5) with catalytic palladium to produce the 1-carbon naphthol coupled CPI 6.

Provenance & Evidence