Reaction #80046

Reaction equation

1-(4-bromophenyl)-cyclopropanecarboxylic acid

Intermediate 114

1-(4-bromophenyl)-cyclopropanecarboxylic acid

diphenylphosphoryl azide

triethylamine

tert-BuOH

→

title compound

Yield 67.0%

Tert-butyl [1-(4-bromophenyl)-cyclopropyl]-carbamate

Yield 67.0%

Conditions

Workup

1. 1
   Temperatureto reflux for 17 h
2. 2
   ConcentrationThe solution was concentrated under reduced pressure
3. 3
   workup.DISSOLUTIONthe residue dissolved in EtOAc
4. 4
   Washwashed with 5% aqueous HCl, H2O, saturated aqueous NaHCO3, and saturated aqueous NaCl
5. 5
   Dryingbefore being dried over MgSO4

Procedure

A solution of 1-(4-bromophenyl)-cyclopropanecarboxylic acid (Intermediate 114, 2.32 g, 9.62 mmols), diphenylphosphoryl azide (2.65 g, 9.62 mmols), triethylamine (973.0 mg, 9.62 mmols) in 40 mL tert-BuOH (distilled from Na°) was heated to reflux for 17 h. The solution was concentrated under reduced pressure and the residue dissolved in EtOAc and washed with 5% aqueous HCl, H2O, saturated aqueous NaHCO3, and saturated aqueous NaCl before being dried over MgSO4. Concentration of the dry solution under reduced pressure and column chromatography (5-10% EtOAc-hexanes) afforded 2.01 g (67%) of the title compound as a colorless solid.

Source