Reacción #159574

Ecuación de reacción

1-(4-bromophenyl)cyclopropanecarboxylic acid

N,N-diisopropylethylamine

Diphenylphosphoryl azide

tert-Butanol

→

title compound ( D4 )

tert-butyl (1-(4-bromophenyl)cyclopropyl)carbamate

Disolventes

toluene

Condiciones de reacción

Tratamiento posterior

1. 1
   TemperaturaThe resulting mixture was refluxed 5 hours
2. 2
   Otrothe solvents evaporated in vacuo
3. 3
   workup.DISSOLUTIONThe residue was dissolved in ethyl acetate (200 ml)
4. 4
   Lavadowashed with 5% citric acid (200 ml), aqueous NaHCO3 (200 ml) and brine (200 ml)
5. 5
   SecadoCollected organics after drying over Na2SO4 and solvent evaporation
6. 6
   Otroafforded a crude residue which
7. 7
   Otrowas purified by flash chromatography on silica gel eluting with a mixture petroleum ether/ethyl acetate 4:1
8. 8
   OtroCollected fractions after solvent evaporation

Procedimiento

To the solution of 1-(4-bromophenyl)cyclopropanecarboxylic acid (40 g, 165 mmol, available from Amatek Chemical #AC-0350) in toluene (800 ml), in the presence of activated molecular sieves (15 g), N,N-diisopropylethylamine (27.5 g, 497 mmol), Diphenylphosphoryl azide (54.7 g, 215 mmol) and tert-Butanol (380 ml) were added. The resulting mixture was refluxed 5 hours. The mixture was cooled to room temperature and the solvents evaporated in vacuo. The residue was dissolved in ethyl acetate (200 ml) and washed with 5% citric acid (200 ml), aqueous NaHCO3 (200 ml) and brine (200 ml). Collected organics after drying over Na2SO4 and solvent evaporation afforded a crude residue which was purified by flash chromatography on silica gel eluting with a mixture petroleum ether/ethyl acetate 4:1. Collected fractions after solvent evaporation afforded the title compound (D4) (23.0 g) as a solid.

Fuente