4-Fluoroaniline → HCID 86708157, compound

Temperature

0 °C

To a solution of 4-fluoroaniline (10 g, 90.0 mmol, 1.0 eq.) in DCM/HOAc (1/1, 180 mL, 0.5M) at 0° C. was added dropwise a precooled solution of sodium nitrite (9.02 g, 108 mmol, 1.2 eq.) in conc. sulfuric acid (40 mL). After stirring for 30 min at 0° C. a mixture of ethyl 4-chloroacetoacetate (14.6 mL, 17.8 g, 108 mmol, 1.2 eq.) in HOAc (60 mL) and H2O (120 mL) was added within 5 min. After further 15 min at 0° C. a solution of sodium acetate (100 g, 1.219 mol, 13.5 eq.) in H2O (210 mL) was added slowly. The mixture was stirred for 30 min at 0° C. and 1 h at RT. DCM (200 mL) was added and the organic phase was separated. The aq. phase was extracted with DCM (3×100 mL). The combined organic phase was washed with water, phosphate buffer and subsequent with brine. The organic layer was dried over Na2SO4 and concentrated under reduced pressure to give the product ethyl 4-chloro-2-(4-fluorophenyl)azo-3-oxo-butanoate as a orange solid. MS (ES) C12H12ClFN2O3 requires: 286. Found: 287 (M+H)+ and 309 (M+Na)+.

1. additionwas added within 5 min
2. stirringThe mixture was stirred for 30 min at 0° C. and 1 h at RT
3. customthe organic phase was separated
4. extractionThe aq. phase was extracted with DCM (3×100 mL)
5. washThe combined organic phase was washed with water, phosphate buffer and subsequent with brine
6. dry with materialThe organic layer was dried over Na2SO4
7. concentrationconcentrated under reduced pressure

ORD record

ord-3589ea38697e4011b8ece540ea31ec2a

Source dataset

uspto-grants-2015_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08999982B2