Hydrochloric Acid → Ethyl 3-(4-carboxy-2-methylphenylhydrazono)-4-oxopentanoate

A mixture of 3 g. (19.8 mmol) of 4-amino-3-methylbenzoic acid in 50 ml. of water and 50 ml. of ethanol and 3.56 ml. of concentrated hydrochloric acid was cooled in an ice bath and then 1.5 g. of NaNO2 (21.8 mmol.) in 10 ml. of water was added portionwise. The mixture was allowed to come to room temperature and then added to a solution of 4.06 g. (21.8 mmol.) of ethyl 3-acetyl-4-oxopentanoate and 8 ml. of pyridine in 25 ml. of ethanol. The reaction mixture was left for 24 hours at room temperature with stirring. The mixture was acidified with concentrated hydrochloric acid and diluted with 20 ml. of water. The resulting solid was collected and washed with water and pentane to yield 5.2 g.

1. additionA mixture of 3 g
2. customto come to room temperature
3. additionadded to a solution of 4.06 g
4. additiondiluted with 20 ml
5. customThe resulting solid was collected
6. washwashed with water and pentane
7. customto yield 5.2 g

ORD record

ord-5b68ae39fb0d454b819718511809b210

Source dataset

uspto-grants-1998_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05821243