Diethyl Ether → Ethylene diamine bis(pentafluorobenzoate)

Participants

Reaction Steps

Ethylene diamine (130 mg, 2.1 mmol) and triethylamine (510 mg, 5.0 mmol), together dissolved in 10 mL anhydrous ether is added to pentafluorobenzoyl chloride (1.2 g, 5.0 mmol) in 10 mL anhydrous ether. White precipitate is obtained and filtered off. The residue is washed with chloroform, then water and then filtered to recover ethylene diamine bis(pentafluorobenzoate) (III) as white needle crystals (yield, 100%). Sodium azide (270 mg, 4.2 mmol) in 1.7 mL water and 4.0 mL DMF is then reacted with III (870 mg, 2.0 mmol) in 20 mL DMF, and stirred overnight on a 60° C. hotplate. A white precipitate is obtained. The solution is reduced to half-volume by evaporation and the precipitate is filtered off (yield, 35%), dried and recrystallised from DMF to give ethylene diamine bis(4-azido-2,3,5,6-tetrafluorobenzoate) (IV) as white crystals. FTIR: 2129 (N3 asymmetric stretch), 1666 (C═O stretch), 1554, 1483, 1242 (N3 symmetric stretch), no acid OH band at 3000-3500.

Provenance & Evidence