Sodium Hydroxide → 3-Bromo-thiophene-2-carbaldehyde oxime

Temperature

0 °C

3-Bromothiophene-2-carbaldehyde (28.7 g, 0.15 mol) in ethanol (50 mL) was added in one portion to a solution of hydroxylamine hydrochloride (13.8 g, 0.2 mol), sodium hydroxide (8 g, 0.2 mol) in water (30 mL) and ethanol (100 mL). The mixture was stirred at 0° C. for 2 hours and was kept at 0° C. overnight when a precipitate formed. The mixture was diluted with cold water (600 ml) and the solid was collected by filtration yielding 20.5 g, (67%). The aqueous solution was further extracted with ethyl acetate. The organic solution was washed with brine, dried with magnesium sulfate, filtered and evaporated yielding 6.9 g of additional product as a light yellow solid. The total yield was 27.4 g (89%).

1. waitwas kept at 0° C. overnight
2. customwhen a precipitate formed
3. filtrationthe solid was collected by filtration
4. customyielding 20.5 g, (67%)
5. extractionThe aqueous solution was further extracted with ethyl acetate
6. washThe organic solution was washed with brine
7. dry with materialdried with magnesium sulfate
8. filtrationfiltered
9. customevaporated

ORD record

ord-6c5fdba8bbf343b288c5e9dac1bb4cde

Source dataset

uspto-grants-2009_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07521445B2