4-Hydroxy-3-nitrobenzoic acid → 2-Nitrophenol

In a 50 mL polystyrene cartridge, to an amino polystyrene resin (1 g, 1.2 mmol) in DMF (15 mL) were added 4-hydroxy-3-nitrobenzoic acid (1a) (1 g, 5.46 mmol), HOBt (1 g, 7.4 mmol), and DIC (1,3-diisopropylcarbodiimide, 1 mL, 6.4 mmol). After overnight shaking, the reaction mixture was washed with DMF (20 mL, 5 times), methylene chloride, and methanol (20 mL, 5 times each). To remove any undesirable side product, DMF (5 mL) and piperidine (0.5 mL) were added to the cartridge and allowed to shake for 1.5 h. The resin was filtered and washed with DMF. The resulting piperidine salt was removed via the addition of a 10% HCl solution (in DMF, 20 mL) to the resin that was allowed to shake for 1.5 h. The mixture was then filtered, washed with DMF (20 mL, 5 times), methanol, and methylene chloride (20 mL, 5 times each) and dried by nitrogen gas flow.

1. washthe reaction mixture was washed with DMF (20 mL, 5 times), methylene chloride, and methanol (20 mL, 5 times each)
2. customTo remove any undesirable side product, DMF (5 mL) and piperidine (0.5 mL)
3. additionwere added to the cartridge
4. waitto shake for 1.5 h
5. filtrationThe resin was filtered
6. washwashed with DMF
7. customThe resulting piperidine salt was removed via the addition of a 10% HCl solution (in DMF, 20 mL) to the resin that
8. waitto shake for 1.5 h
9. filtrationThe mixture was then filtered
10. washwashed with DMF (20 mL, 5 times), methanol, and methylene chloride (20 mL, 5 times each) and
11. customdried by nitrogen gas flow

ORD record

ord-5efb9304032a4831994f4990288679ff

Source dataset

uspto-grants-2006_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07060752B2