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A reaction was carried out in acetonitrile (425 mL) with 2,4-dichlorothiazole (34 g, 0.22 mol) and morpholine (21.2 mL, 0.225 mol). Potassium carbonate (60.9 g, 0.44 mol) was first added to the reaction system, followed by slow dropwise addition of morpholine over 30 min. The reaction mixture was refluxed at 40 °C and cooled to 22 °C upon completion. The reaction solution was filtered and the filtrate was evaporated to remove the solvent. The residue was ground with isopropanol (60 mL) at 22 °C for 1 h to promote crystallization. The solid product was collected by filtration and dried under vacuum to constant weight to give the final 4-(4-chlorothiazol-2-yl)morpholine (34.5 g, 76% yield). The product was confirmed by electrospray mass spectrometry (ES/MS), m/z (35Cl) 205 (M + 1)+.

[1] Patent: WO2008/36579, 2008, A1. Location in patent: Page/Page column 37
[2] Patent: WO2008/83070, 2008, A1. Location in patent: Page/Page column 63
[3] Patent: WO2005/28444, 2005, A1. Location in patent: Page/Page column 73