Patent ID: 7479563
Filing Date: 2009-01-20
Classification: A61P,C07D

Abstract:
1. A method of producing a crystalline form (III) of donepezil hydrochloride (chemical name: 1-benzyl-4-[(5,6-dimethoxy-1-indanon)-2-yl]methylpiperidine•monohydrochioride) represented by the following structural formula 1: by the steps of: dissolving donepezil (chemical name: 1-benzyl-4-[(5,6-dimethoxy-1-indanon)-2-yl]methylpiperidine) in ethanol; adding hydrochloric acid or hydrogen chloride thereto; stirring while keeping the internal temperature at 10 to 40° C.; and then collecting by filtration and drying the resulting crystals; wherein the crystalline form (III) of donepezil hydrochloride is a crystalline form having peaks at the following diffraction angles (2θ) in its powder X-ray diffraction patterns; with absorption at the following wave numbers in its infrared absorption spectrum in potassium bromide: 559, 641, 648, 702, 749, 765, 786, 807, 851, 872, 927, 949, 966, 975, 982, 1007, 1034, 1071, 1080, 1111, 1119, 1131, 1177, 1190, 1205, 1217, 1230, 1250, 1265, 1292, 1313, 1367, 1389, 1420, 1438, 1453, 1461, 1470, 1500, 1589, 1605, 1697, 2407,2419, 2461, 2624, 2641, 2651, 2667, 2837, 2848, 2873, 2924, 2954, 2961, 2993, 3007, 3377, 3433 cm −1 ; or a crystalline form having peaks at the following diffraction angles (2θ) in its powder X-ray diffraction patterns; with absorption at the following wave numbers in its infrared absorption spectrum in potassium bromide: 558.3, 641.1, 702.4, 748.5, 765.0, 786.1, 807.3, 850.8, 872.0, 926.8, 974.9, 1034.1, 1071.5, 1111.6, 1190.1, 1216.6, 1265.4, 1291.9, 1312.9, 1364.4, 1420.2, 1438.1, 1458.8, 1499.1, 1522.2, 1542.6, 1560.1, 1570.2, 1589.1, 1638.8, 1647.8, 1654.3, 1697.3, 1718.1, 1734.5, 1751.4, 1773.7, 1793.5, 1845.8, 2345.3, 2461.6, 2924.2, 3447.9 cm −1 .