Hydrochloric Acid → 1-(2-Fluoro-4-chloro-5-hydroxyphenyl)-3,4,5-trimethylpyrazole

HRID 580257Notes

Reaction equation

[F:1][C:2]1[CH:7]=[C:6]([Cl:8])[C:5]([O:9]S(C)(=O)=O)=[CH:4][C:3]=1[N:14]1[C:18]([CH3:19])=[C:17]([CH3:20])[C:16]([CH3:21])=[N:15]1.[OH-].[Na+].Cl>C(O)C>[F:1][C:2]1[CH:7]=[C:6]([Cl:8])[C:5]([OH:9])=[CH:4][C:3]=1[N:14]1[C:18]([CH3:19])=[C:17]([CH3:20])[C:16]([CH3:21])=[N:15]1

Participants

Conditions

Temperature: 40 °C

Procedure

A mixture of 1-(2-fluoro-4-chloro-5-methylsulfonyloxyphenyl)- 3,4,5-trimethylpyrazole (33.3 g), 2N aqueous sodium hydroxide (100 ml) and ethanol (50 ml) was stirred at 40° C. for 30 minutes. After cooling, the reaction mixture was acidified with aqueous hydrochloric acid and then extracted wth toluene. The toluene layer thus obtained was washed with water and dried over anhydrous sodium sulfate. Removal of the solvent by distillation in vacuo gave the titled compound (24.2 g) as a pale yellow crystalline solid. Recrystallization of this solid from a mixture of n-hexane/ethyl acetate yielded a white crystalline solid. m.p. 158°-160° C.

Workup

temperatureAfter cooling
extractionextracted wth toluene
customThe toluene layer thus obtained
washwas washed with water
dry with materialdried over anhydrous sodium sulfate
customRemoval of the solvent
distillationby distillation in vacuo

Sources & evidence

ORD record: ord-f5fb9f8a334f4c218a4fce06a16ca2ff
Source dataset: uspto-grants-1988_06
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US04752326

Reaction notes

Loading…