(2,5-dioxopyrrolidin-1-yl) 5-azidopentanoate

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

Procedure: To a suspension of 5-azidovaleric acid (715 mg; 5 mmol; Example 2.2) and N-hydroxysuccinimide (632 mg; 5.5 mmol; Aldrich) in 30 ml dichloromethane, was added 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (1.05 g; 5.5 mmol; Aldrich), and the reaction was stirred 12 h at room temperature. To the reaction mixture, was added water (50 ml), and the separated organic phase was washed with water (100 ml) and brine (100 ml), dried over sodium sulfate, dried in vacuo. The product was purified via flash chromatography on silica gel (240-400 mesh) in 3:1 (v/v) hexane:ethyl acetate. Yield: 843 mg (3.5 mmol, 70% yield). M+H+: expected, 241.09.7; found, 241.03. the separated organic phase was washed with water (100 ml) and brine (100 ml) dried over sodium sulfate dried in vacuo The product was purified via flash chromatography on silica gel (240-400 mesh) in 3:1 (v/v) hexane

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

Procedure: To a suspension of 5-azidovaleric acid (715 mg; 5 mmol; Example 2.2) and N-hydroxysuccinimide (632 mg; 5.5 mmol; Aldrich) in 30 ml dichloromethane, was added 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (1.05 g; 5.5 mmol; Aldrich), and the reaction was stirred 12 h at room temperature. To the reaction mixture, was added water (50 ml), and the separated organic phase was washed with water (100 ml) and brine (100 ml), dried over sodium sulfate, dried in vacuo. The product was purified via flash chromatography on silica gel (240-400 mesh) in 3:1 (v/v) hexane:ethyl acetate. Yield: 843 mg (3.5 mmol, 70% yield). M+H+: expected, 241.09.7; found, 241.03. the separated organic phase was washed with water (100 ml) and brine (100 ml) dried over sodium sulfate dried in vacuo The product was purified via flash chromatography on silica gel (240-400 mesh) in 3:1 (v/v) hexane

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

Procedure: To a suspension of 5-azidovaleric acid (715 mg; 5 mmol; Example 2.2) and N-hydroxysuccinimide (632 mg; 5.5 mmol; Aldrich) in 30 ml dichloromethane, was added 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (1.05 g; 5.5 mmol; Aldrich), and the reaction was stirred 12 h at room temperature. To the reaction mixture, was added water (50 ml), and the separated organic phase was washed with water (100 ml) and brine (100 ml), dried over sodium sulfate, dried in vacuo. The product was purified via flash chromatography on silica gel (240-400 mesh) in 3:1 (v/v) hexane:ethyl acetate. Yield: 843 mg (3.5 mmol, 70% yield). M+H+: expected, 241.09.7; found, 241.03. the separated organic phase was washed with water (100 ml) and brine (100 ml) dried over sodium sulfate dried in vacuo The product was purified via flash chromatography on silica gel (240-400 mesh) in 3:1 (v/v) hexane