Crystal structure of 2-(8a-methyl-5-oxo-hexahydroimidazo [1,2-a]pyridin-1(5H)-yl)-2-oxoethyl acetate, C₁₂H₁₈N₂O₄

Abstract

CCDC no.: 1532367The crystal structure is shown in the figure. Table 2 lists the atoms with their coordinates and displacement parameters. Source of materialsEthyl 4-acetylbutyrate (0.05 mol) and ethylenediamine (0.14 mol) were mixed with 25 mL EtOH, refluxed for 8 h, and then the solvent was removed via vacuum distillation. The intermediate 5-methyl-9-oxa-1,4-diazabicyclo[3.4.0]nonane was purified by column chromatography on silica gel eluting with CH 2 Cl 2 and EtOH (6:1). (Et) 3 N (1.72 g, 0.017 mol) was added to the intermediate (0.007 mol) in THF (30 mL) at 0-5°C. Acetoxyacetyl chloride (0.01 mol) was added dropwise to the mixture. The reaction was quenched with water. The solution was washed with sat. NH4Cl (aq), sat. Na 2 CO 3 (aq), and water. The organic phase was dried over anhydrous MgSO4. After removal of the solvent, the products were crystallized from EtOH and light petroleum as a white solid with 52.1% yield. Experimental detailsThe C-H atoms were constrained to an ideal geometry, with C-H distances of 0.96-0.97 Å. The U iso values of the hydrogen atoms of methyl groups were set to 1.5Ueq(C methyl ) and the U iso values of all other hydrogen atoms were set to 1.2Ueq(C).