Homophthalic acid → 3-(4-Methoxybenzyl)isocoumarin

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A well-stirred mixture of homophthalic acid (10 g; 56 mmol) and 2-(4-methoxyphenyl)acetyl chloride (10 g, 230 mmol) was heated at 200° C. for 3 hours under nitrogen then cooled to 50° C. and dissolved in toluene (100 ml), The solvent was removed in vacuo and the residue was dissolved in methanol (100 ml). Silica (30 g) was added and the solvent was removed in vacuo. The crude product, thereby adsorbed onto silica, was applied to the top of a column of silica and purified by chromatography using 10-50% mixtures of ethyl acetate and hexane as eluant. Appropriate fractions were combined and the solvents removed in vacuo to give 3-(4-methoxybenzyl)isocoumarin (0.9 g, 26%) as an oil; δH 3.75 (3H, s), 3.80 (2H, s), 6.50 (1H, s), 6.95 (2H, d, J=8.9 Hz), 7.30 (2H, d, J=8.9 Hz), 7.40-7.90 (3H, m), 8.10 (1H, d); m/z (M+H)+. 267.

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