Triethylamine → 4-[4-(Hydroxyaminocarbonyl)methoxy-3,5-dimethyphenyl]-2-methyl-1(2H)phthalazinone

A solution of example 108 (1.15 g) in dichloromethane (30 ml) at 0° C. was treated with triethylamine (0.52 g) followed by isopropenyl chloroformate (0.41 g), and the mixture was stirred for 1 h. O-tert-butyldimethylsilylhydroxylamine (0.50 g) was then added and the mixture was stirred for a further 18 h. The reaction mixture was washed with 10% citric acid (20 ml), saturated sodium bicarbonate (20 ml) and the concentrated to dryness in vacuo. A solution of the residual solid in tetrahydrofuran (30 ml) and water (5 ml) was then treated with a 1.0 M solution of tetrabutylammonium fluoride in tetrahydrofuran (1 ml) and stirred 1 h. the resultant crude mixture was concentrated on to silica and purified by chromatography, eluting with 5% methanol in dichloromethane, to provide the title compound as a white solid (0.10 g).

1. stirringthe mixture was stirred for a further 18 h
2. washThe reaction mixture was washed with 10% citric acid (20 ml), saturated sodium bicarbonate (20 ml)
3. concentrationthe concentrated to dryness in vacuo
4. additionA solution of the residual solid in tetrahydrofuran (30 ml) and water (5 ml) was then treated with a 1.0 M solution of tetrabutylammonium fluoride in tetrahydrofuran (1 ml)
5. stirringstirred 1 h. the resultant crude mixture
6. concentrationwas concentrated on to silica
7. custompurified by chromatography
8. washeluting with 5% methanol in dichloromethane

ORD record

ord-9426c33c39d645d5912c2f442d801282

Source dataset

uspto-grants-2003_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06566384B1