Methyl 2-(4-chloro-2-nitrophenyl)acetate → Methyl (4-chloro-2-[N-hydroxyamino] phenyl)acetate

Methyl (2-nitro-4-chlorophenyl)acetate (5.0 g, 21.7 mmol) was dissolved in 250 ml of tetrahydrofuran and 15 ml of dimethyl sulfoxide. To this was added 900 mg of 10% Pd/C. A solution of 5.38 g of sodium hypophosphite in 18 ml of water was added dropwise over a 40 minute period. After stirring for 4 hours another 2.68 g of sodium hypophosphite (in 8 ml of water) was added over a 10 minute period. After stirring for one hour the reaction mixture was filtered through Celite and the filtrate diluted with 500 ml of CH2Cl2. The filtrate was washed with saturated aqueous NaHCO3 then brine and dried with Na2SO4. The solvents were evaporated under reduced pressure leaving 5.16 g of a yellow oil (110% of theory). NMR (300 MHz, CDCl3): 3.51 (2 H, s), 3.69 (3 H, s), 5.50 (1 H, br s), 6.88 (1 H, dd, J=1,8), 7.01 (1 H, d, J=8), 7.34 (1 H, d, J=1), 7.56 (1 H, br s).

1. additionwas added over a 10 minute period
2. filtrationwas filtered through Celite
3. additionthe filtrate diluted with 500 ml of CH2Cl2
4. washThe filtrate was washed with saturated aqueous NaHCO3
5. dry with materialbrine and dried with Na2SO4
6. customThe solvents were evaporated under reduced pressure

ORD record

ord-f0610779bfc942a68ac197df9e39b9f1

Source dataset

uspto-grants-1992_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05166401