Crystal structure of (±)-2-imidazol-1-ylsuccinic acid, C7H8N2O4

Abstract

C 7 H 8 N 2 O 4 ,monoclinic, P12 1 /c1(no. 14), a =7.649(2) Å, b =7.493(2) Å, c =13.770(2) Å, b =96.73(2)°, V =783.8 Å 3 , Source of materialThe title compound was synthesized acoording to the reported method [1]. The neat reaction of imidazole (5 g, 73.53 mmol) and diethyl fumarate (12.65 g, 73.53 mmol) at 373 Kfor 24 hgives diethyl(±)-2-imidazol-1-ylsuccinate (I,1 3.30 . g, 75 . %). Then I (0.5 .g, 2.08 mmol) was dissolved in 1Ma queous hydrochloric acid (20 ml) and heated at 373 Kfor 6h.1MNaOH was dropwise added to the resulting solution until white solid was afforded. Then the white solid was filtrated and dissolved in aqueous solution, which was kept undisturbed at room temperature. After 2 weeks, colorless crystals suitable for X-ray diffraction were obtained (35.7 %yield, based on I). DiscussionThe title compound exists in zwitterion form in the solid state. It is as imilar behavior to the discovered for 1-substituted imidazol carboxylic ramifications where the proton from carboxylic O atom migrates to the Natom belonging to imidazole ring [2]. The five-membered imidazole ring is essentially planar with the maximal deviation of 0.003 Å of the plane (C2, C3, N1, C1, N2