tert-butyl N-(3-oxo-3-pyrrolidin-1-ylpropyl)carbamate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2-(7-Aza-1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate (5.9 g, 15.4 mmol), pyrrolidine (3.2 g, 16.8 mmol) and diisopropylethylamine (5.4 mL, 42.2 mmol) was added to a suspension of 3-((tert-butoxycarbonyl)amino)propanoic acid (1.0 g, 14.0 mmol) in dichloromethane (20 mL) and the resulting mixture was stirred at ambient temperature for 6 hours. TLC analysis showed no acid remaining so the mixture was diluted with dichloromethane and washed with water and brine. The organic layer was separated, dried (Na2SO4), filtered and the solvent was removed to afford a solid. The crude material was purified by silica gel chromatography using a 70:30 mixture of hexane and ethyl acetate as eluent to afford the title product as a solid (3.0 g, 88% yield). MS m/z: 243.26 [M+H]+. washed with water and brine The organic layer was separated dried (Na2SO4) filtered the solvent was removed to afford a solid The crude material was purified by silica gel chromatography a 70:30 mixture of hexane and ethyl acetate as eluent