| preparation | 2-piperazine ethanol dihydrochloride was prepared as follows: to an ice-bath cooled mixture of ethyl 3-oxo-piperazin-2-yl acetate (2.0g,10.74mmol) in 50ml of anhydrous THF under N2 was added, under stirring, Dropwise, in THF, 20.0mL,20.0mmol). When the dropwise addition was complete (c.10 min), the reaction mixture was refluxed for 31/2 H and then cooled in an ice bath. Water (5ml) was carefully added with stirring. After stirring for 1/2 hour, the mixture was filtered with a frit® funnel and the collected salts were washed with hot EtOH. The filtrates were combined, dried over MgSO4, filtered and the solvent removed in vacuo. The residue was treated with hot CHCl3, filtered and removed by evaporation to give 2-piperazineethanol dihydrochloride as a pale yellow oil. The product was obtained in quantitative yield and was used without further purification. |
