Reaction #3225

Reaction equation

water

N-(tert-butoxycarbonyl)-3-chloro-5-trifluoromethylaniline

tetrahydrofuran

t-butyllithium

Dry Ice

→

title compound

Yield 82.0%

2-(tert-Butoxycarbonyl)-6-chloro-4-trifluoromethylbenzoic acid

Yield 82.0%

Solvents

pentane

Conditions

Workup

1. 1
   TemperatureThe temperature of the reaction mixture was maintained at -103° to -98° C. during the addition and for 3.25 hr
2. 2
   workup.ADDITIONafter the addition
3. 3
   ExtractionThe resulting mixture was extracted with ethyl acetate
4. 4
   Dryingthe combined extracts were dried (MgSO4)
5. 5
   Filtrationfiltered
6. 6
   Concentrationconcentrated

Procedure

To a cold (-100° C.) stirred solution of N-(tert-butoxycarbonyl)-3-chloro-5-trifluoromethylaniline 93.4 g, 11.5 mM) in dry tetrahydrofuran (30 mL) under a nitrogen atmosphere was added dropwise t-butyllithium (14.2 mL of 1.7 M solution, 24.2 mM) in pentane. The temperature of the reaction mixture was maintained at -103° to -98° C. during the addition and for 3.25 hr after the addition was completed. Crushed Dry Ice was then added to the cold reaction mixture which, after being allowed to warm to -75° C., was poured into water. The resulting mixture was extracted with ethyl acetate and the combined extracts were dried (MgSO4), filtered and concentrated to leave (3.2 g, 82%) the title compound as a solid white foam.

Source