反应详情

Methyl 7-bromo-3-oxo-3,4-dihydro-2H-pyrido[3,2-b][1,4]thiazine-6-carboxylate (Example 304b) (2.00 g, 6.6 mmol), tetraethyltin (3.17 mL, 16 mmol) and bis(triphenylphosphine)palladium(II) chloride (1.12 g, 1.6 mmol) in dimethylformamide (40 mL) were heated at 120° C. for 24 h. The mixture was filtered through Kieselguhr, washed through with ethyl acetate and evaporated. Chromatography on silica gel (20-50% ethyl acetate/petroleum ether) gave a mixture of the 7-ethyl and 7-vinyl compounds (0.29 g). This mixture was hydrogenated in methanol/ethyl acetate (2:1, 60 mL) over 10% palladium on carbon (60 mg) (1 atmosphere, room temperature) for 24 h. Filtration and evaporation of solvent gave the product (0.28 g).

1. filtrationThe mixture was filtered through Kieselguhr
2. washwashed through with ethyl acetate
3. customevaporated
4. customChromatography on silica gel (20-50% ethyl acetate/petroleum ether) gave
5. filtrationFiltration and evaporation of solvent