Hydrochloric Acid → 5-Hydroxy-4-methoxy-2-nitrobenzaldehyde

3-Hydroxy-4-methoxybenzaldehyde (15.2 g, 0.1 mol) obtained in the same manner as in Reference Example 3 was dissolved in THF (150 ml), to which sodium nitrate (8.5 g, 0.1 mol) and lanthanum nitrate hexahydrate (8.7 g, 0.2 mol) were added, and then a mixture of concentrated hydrochloric acid and water at a ratio of 1:1 (70 ml) was added dropwise over a period of 20 minutes. The mixture was stirred for 40 minutes at room temperature, and the separated organic layer was successively washed with water (50 ml), a saturated aqueous solution of sodium hydrogencarbonate (50 ml), and a saturated aqueous solution of sodium chloride (100 ml), dried over anhydrous magnesium sulfate, filtered to remove the desiccating agent, and concentrated under reduced pressure to give a mixture of the title compounds 4a and 4b as pale red crystals (4a:4b=1:1, 13.3 g, yield 67.5%) (Table 2).

1. additionwere added
2. additionwas added dropwise over a period of 20 minutes
3. washthe separated organic layer was successively washed with water (50 ml)
4. dry with materiala saturated aqueous solution of sodium hydrogencarbonate (50 ml), and a saturated aqueous solution of sodium chloride (100 ml), dried over anhydrous magnesium sulfate
5. filtrationfiltered
6. customto remove the desiccating agent
7. concentrationconcentrated under reduced pressure
8. customto give

ORD record

ord-8bb025d810a546038724b55a806d28d2

Source dataset

uspto-grants-2004_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06806276B2