反应详情

An alternative but less satisfactory synthesis was conducted as follows: A mixture of 7-bromo-9,9-diethylfluorene-2-carboxaldehyde (3.29 g, 10.0 mmol), hydroxylamine hydrochloride (0.9 g, 10.0 mmol), and formic acid (15 mL), was held at reflux for 2 hr, cooled and filtered. The filtrate was worked up by extraction into toluene, washing the extract with water, and bicarbonate solution, drying and concentration. The residue was combined with the formic acid-insoluble solids and chromatographed over silica gel. There were obtained, the desired aldehyde product, 1.58 g (49%), m.p. 85-87° C., mass spectrum (m/z): 325, 327 (M+); the amide by-product, 0.42 g (12%), m.p. 179-184° C., mass spectrum (m/z): 343,345 (M+); and the oxime by-product, m.p. 104-107° C., 0.17 g (5%), mass spectrum (m/z): 343 (M+)

1. customAn alternative but less satisfactory synthesis
2. temperatureat reflux for 2 hr
3. temperaturecooled
4. filtrationfiltered
5. extractionThe filtrate was worked up by extraction into toluene
6. washwashing the
7. extractionextract with water, and bicarbonate solution
8. customdrying
9. concentrationconcentration
10. customchromatographed over silica gel
11. customThere were obtained