反应详情

A solution of 4-[4-(4-fluorophenoxy)benzenesulfonylamino]tetrahydropyran-4-carboxylic acid N-benzyloxyamide(11.28 grams, 0.0225 mole) in ethyl acetate (600 mL) was treated with 5% palladium on barium sulfate (5.0 grams) and hydrogenated in a Parr™ shaker at 3 atmospheres pressure for 18 hours. After filtration through nylon (pore size 0.45 mm) to remove the catalyst, the filter pad was rinsed with methanol. Combined filtrate and rinse were evaporated and the residue taken up in hot methanol. Cooling afforded crude 4-[4-(4-fluorophenoxy)benzenesulfonylamino]-tetrahydropyran-4-carboxylic acid hydroxyamide (5.941 grams, 64%, mp 176-177° C.) as a white crystalline solid. The mother liquor was evaporated and the residue crystallized from 50% methanoldichloromethane to give additional 4-[4-(4-fluorophenoxy)benzenesulfonylamino]-tetrahydropyran-4-carboxylic acid hydroxyamide (0.660 grams, mp 184-185° C.) as white needles. The mother liquor was again evaporated and the residue crystallized from methanol/dichloromethane to give additional product (1.861 grams, mp 176-177° C.). Recrystallization of the first lot from methanol/dichloromethane provided analytically pure 4-[4-(4-fluorophenoxy)benzenesulfonylamino]tetrahydropyran-4-carboxylic acid hydroxyamide (3.091 grams, mp 184-185° C.).

1. filtrationAfter filtration through nylon (pore size 0.45 mm)
2. customto remove the catalyst
3. washthe filter pad was rinsed with methanol
4. washCombined filtrate and rinse
5. customwere evaporated
6. temperatureCooling
7. customafforded crude 4-[4-(4-fluorophenoxy)benzenesulfonylamino]-tetrahydropyran-4-carboxylic acid hydroxyamide (5.941 grams, 64%, mp 176-177° C.) as a white crystalline solid
8. customThe mother liquor was evaporated
9. customthe residue crystallized from 50% methanoldichloromethane