反应详情

To a suspension of (Z)-5-fluoro-2-methyl-1-(4-methylthiobenzylidene) inden-3-ylacetic acid (U.S. Pat. No. 3,647,858; U.S. Pat. No. 3,654,349; J.O.C. Vol. 42, 1914-1919 (1977) (130 mg, 0.38 mmol) in methylene chloride (3 mL) at room temperature there was added oxalyl chloride (96.5 mg, 0.76 mmol) and one drop of N, N-dimethylformamide (DMF). When gassing had subsided another drop of DMF was added and stirring was continued for 30 minutes. This solution was added, at 0° C., to a mixture of N-methyl hydroxylamine hydrochloride (125 mg, 1.5 mmol) and triethylamine (253 mg, 2.5 mmol) in tetrahydrofuran (THF) (5 mL). After 30 minutes at 0° C., the mixture was diluted with water and ethyl acetate and acidified with iN aqueous HCl. The crude product from the organic extract was crystallized from a mixture of ethyl acetate and hexane to afford the title product as yellow-orange crystals, mp: slow decomp. from 118° C.

1. additionwas added
2. waitAfter 30 minutes at 0° C.
3. extractionThe crude product from the organic extract
4. customwas crystallized from a mixture of ethyl acetate and hexane