C10H12ClNO, monoclinic, C12/c1 (no. 15), a = 21.459(2) A, b = 5.6893(6) A, c = 17.760(2) A, ) = 105.137(2)°, V = 2093.1 A, Z = 8, Rgt(F) = 0.066, wRref(F) = 0.190, T = 298 K. Source of material All reagents and solvents were used as purchased without further purification. 5-chloro-2-hydroxybenzaldehyde (147 mg, 1 mmol), propan-2-amine (118 mg, 2 mmol) were dissolved in methanol (15 mL). The mixture was refluxd for a period of 8 h and, after cooling to room temperature, was filtered. The filtrate was kept still in air for one week. Large block-shaped crystals were precipitated. They were filtered and washed with ethanol and dried in a vacuum desiccator using anhydrous CaCl2 (yield 89 %). Experimental details All H atoms were positioned geometrically and refined as riding with d(C—H) = 0.93 0.98 A), Uiso(H) = 1.2 or 1.5 Ueq(C), respectively. The instability of isopropyl group and the poor quality of the crystals result in quite large residual values. Discussion Extended interest to the Schiff bases is caused by their use as startingmaterials in the synthesis of important drugs, such as antibiotics and antimalarial, antifungal, and antitumor substances [15], as components of rubber compounds [6], or as ligands for the complexation of metal ions [7-9]. The bond lengths and angles in the title crystal structure are in normal ranges. The C7=N1 bond length of 1.263(4) A conforms to the value of a double bond. The torsion angleN1–C7–C1–C6 is –178.94(3)°. In the crystal packing, the molecules are linked by several weak intermolecular C–H···O interactions. Z. Kristallogr. NCS 225 (2010) 567-568 / DOI 10.1524/ncrs.2010.0248 567 © by Oldenbourg Wissenschaftsverlag, Munchen Crystal: yellow block, size 0.13 × 0.21 × 0.32 mm Wavelength: Mo K* radiation (0.71073 A) -: 3.26 cm−1 Diffractometer, scan mode: Bruker SMART CCD, #/% 2+max: 53° N(hkl)measured, N(hkl)unique: 6601, 2155 Criterion for Iobs, N(hkl)gt: Iobs > 2 ((Iobs), 1755 N(param)refined: 121 Program: SHELXTL [10] Table 1. Data collection and handling. H(1) 8f 0.0753 0.3538 0.2691 0.129 H(3) 8f 0.1186 0.5580 0.1155 0.085 H(4) 8f 0.1912 0.3766 0.0593 0.083 H(6) 8f 0.2143 −0.1420 0.2160 0.068 H(7) 8f 0.1569 −0.1417 0.3181 0.067 H(8) 8f 0.1191 −0.1426 0.4202 0.081 H(9A) 8f 0.1246 0.2348 0.4733 0.151 H(9B) 8f 0.0784 0.0770 0.5069 0.151 H(9C) 8f 0.0496 0.2614 0.4415 0.151 H(10A) 8f −0.0130 −0.0494 0.3577 0.158 H(10B) 8f 0.0148 −0.2445 0.4197 0.158 H(10C) 8f 0.0227 −0.2676 0.3347 0.158 Table 2. Atomic coordinates and displacement parameters (in A). Atom Site x y z Uiso