3,3-Dichloro-1-(4-nitrophenyl)-2-piperidinone is an intermediate in the synthesis of the anticoagulant, Apixaban (Zikria and Ansell, Reference Zikria and Ansell2009; Jiang and Ji, Reference Jiang and Ji2013). The sample was prepared using 1-(4-nitrophenyl)-2-piperidinone and was recrystallized in methanol and dried. The sample was then ground into powder (HPLC ≥ 98%, ρ = 1.493 g cm⁻³, T _melt = 130–132 °C) and mounted on a flat zero background plate. X-ray powder diffraction measurement was performed at room temperature using an X'Pert PRO diffractometer (PANalytical Co., Ltd., Netherlands) with a PIXcel 1D detector and CuKα radiation (generator setting: 40 kV and 40 mA). The diffraction data were collected over the angular range from 4° to 50°2θ with a step size of 0.01313°2θ and a counting time of 70 ms step⁻¹. The software package Material Studio 8.0 (Accelrys Co., Ltd. USA) was used to process the data in the Analytical & Testing Center (Sichuan University, Chengdu, China). The X-ray powder diffraction pattern was pre-treated by subtracting the background, smoothing, and stripping off the Kα ₂ component. Automatic indexing results were obtained by DICVOL91 method (Boultif and Louër, Reference Boultif and Louër1991). The following figures of merit were achieved: F ₂₆ = 85.6 (0.0049, 62) (Smith and Snyder, Reference Smith and Snyder1979) and M ₂₆ = 27.5 (de Wolff, Reference de Wolff1968). The preliminary cell from indexing was refined using the Pawley method (Pawley, Reference Pawley1981). Pawley refinement results confirmed that the sample crystallizes in the triclinic space group P-1(2), with a = 11.088(4) Å, b = 11.594(5) Å, c = 12.689(3) Å, α = 118.456(1)°, β = 100.320(3)°, γ = 107.763(3)°, V = 1259.27 Å³, Z = 4, and ρ _x  = 1.525 g cm⁻³. Figure 1 shows the powder X-ray diffraction pattern of the compound.

Figure 1.

Powder X-ray diffraction pattern of 3,3-dichloro-1-(4-nitrophenyl)-2-piperidinone.