Reaction #696727

Reaction equation

3-cyclopentene-1-carboxylic acid

triethylamine

diphenylphosphoryl azide

t-butanol

→

tert-Butyl N-(3-cyclopenten-1-yl)carbamate

Conditions

Workup

1. 1
   TemperatureThe solution was maintained at 60
2. 2
   workup.WAITcontinued at ambient temperature for 18 hours
3. 3
   OtherVolatiles were evaporated
4. 4
   workup.DISSOLUTIONthe residue was dissolved in methylene chloride (1250 mL)
5. 5
   Washwashed with 10 % aqueous sodium carbonate (2×250 mL)
6. 6
   Dryingdried (magnesium sulfate)
7. 7
   OtherVolatiles were evaporated
8. 8
   Otherthe residue was chromatographed on a silica gel column
9. 9
   WashTitle compound was eluted with chloroform as white crystals, from hexanes (22.63 g, 47%), m.p. 68-70° C.

Procedure

To a solution of 3-cyclopentene-1-carboxylic acid (J.-P. Depres and A. E. Greene, J. Org. Chem. 1984, 49:928-931; 29.71 g, 0.261 mole), triethylamine (36.4 mL) in t-butanol (1 L) was added diphenylphosphoryl azide, Aldrich, 97%, 74.0 g, 0.261 mmole). The solution was maintained at 60--C. for 4 hours. Cuprous chloride (1.3 g) was added and stirring continued at ambient temperature for 18 hours. Volatiles were evaporated and the residue was dissolved in methylene chloride (1250 mL) and washed with 10 % aqueous sodium carbonate (2×250 mL) and dried (magnesium sulfate). Volatiles were evaporated and the residue was chromatographed on a silica gel column. Title compound was eluted with chloroform as white crystals, from hexanes (22.63 g, 47%), m.p. 68-70° C.

Source