Reaction #1929073

Reaction equation

triethylamine

compound

Methyl 1-amino-4,4-difluorocyclohexanecarboxylate hydrochloride

thionyl chloride

(5-bromo-2-methylphenyl)acetic acid

→

Methyl 1-{[(5-bromo-2-methylphenyl)acetyl]amino}-4,4-difluorocyclohexanecarboxylate

Solvents

THF

solution A

tetrahydrofuran

Conditions

Workup

1. 1
   Concentrationconcentrated
2. 2
   workup.DISSOLUTIONThe residue was dissolved in 100 ml of tetrahydrofuran (THF) (solution A)
3. 3
   Temperaturewith cooling
4. 4
   workup.STIRRINGthe mixture was stirred at room temperature until the reaction
5. 5
   FiltrationThe precipitate is filtered off with suction
6. 6
   Washwashed with THF
7. 7
   Concentrationthe filtrate is concentrated under reduced pressure
8. 8
   Otherthe residue is recrystallized from methyl tert-butyl ether

Procedure

36.5 ml (500 mmol) of thionyl chloride were added to 22.91 g (100 mmol) of (5-bromo-2-methylphenyl)acetic acid (EP 1791816 A1 and WO 2006/29799 A1), and the mixture was stirred at 80° C. until the evolution of gas was complete and then concentrated. The residue was dissolved in 100 ml of tetrahydrofuran (THF) (solution A). 25.3 g (110 mmol) of the compound from Example 4A were initially charged in 308 ml of THF, 21.3 ml of triethylamine were added dropwise at 20° C., solution A was then added dropwise with cooling and the mixture was stirred at room temperature until the reaction had gone to completion. The precipitate is filtered off with suction and washed with THF, the filtrate is concentrated under reduced pressure and the residue is recrystallized from methyl tert-butyl ether. This gave 33.6 g (83% of theory) of the title compound.

Source