C 12 H 14 N 2 O 2 ,monoclinic, P12 1 /n1(no. 14), a =13.0062(3) Å, b =6.0105(1) Å, c =15.6960(4) Å, b =108.359(1)°, V =1164.6 Å 3 , Z =4,R gt (F) =0.043,
Source of materialThe title compound has been obtained by regioselective N3-alkylation reaction of 5,5-dimethylimidazolidine-2,4-dione with benzyl bromide (1 equiv.) in dry N,N-dimethylformamide in the presence of potassium carbonate as ab ase [1,2]. The heterogeneous solution was heated at 85°Cfor six hours and concentrated in vacuo. The residue was diluted with water and the mixture extracted with dichloromethane. The combined organic extracts were dried with sodium sulfate and evaporated to give the title compound as ac olourless oil. Colourless needle-like crystals, suitable for X-ray structure analysis were obtained after slow evaporation of the solvent (dichloromethane/petroleum ether, 1:5, v/v)overnight at 273 Kand crystallization over aperiod of several days at 268 K(mp. 381 -383 K).
DiscussionThe crystal structure contains 4symmetry-equivalent molecules per unit cell. All intramolecular bond lengths are normal. The main part of the molecule consists of an almost planar aromatic system (N1, C2, N3, C4, C5, O8, O9, C10) with an r.m.s. value of the deviations from the least squares plane of 0.018 Å.Asecond plane, which is defined by C10, C11, C12, C13, C14, C15, C16 with r.m.s. =0.009 Å,istilted by 85.83(3)°against the first. A third plane, defined by C5, C6 and C7, is tilted against the second one by 89.03 (8)