[BH4-].[Li+].[CH2:3]([C:5]1[C:6]([O:20][CH3:21])=[N:7][C:8]2[N:9]([CH:12]=[C:13]([C:15](OCC)=[O:16])[N:14]=2)[C:10]=1[CH3:11])[CH3:4].[BH4-]>O1CCCC1>[CH2:3]([C:5]1[C:6]([O:20][CH3:21])=[N:7][C:8]2[N:9]([CH:12]=[C:13]([CH2:15][OH:16])[N:14]=2)[C:10]=1[CH3:11])[CH3:4]11.55 g (0.525 mol) of lithium borohydride were added portionwise over 1 hour to a stirred solution of 19.7 g (75 mmol) of ethyl 6-ethyl-7-methoxy-5-methylimidazo[1,2-a]pyrimidine-2-carboxylate in 300 ml of dry tetrahydrofuran and after stirring at room temperature for 18 hours the excess borohydride was destroyed by dropwise addition of 300 ml of saturated sodium chloride solution. Then, the mixture was stirred for 30 minutes before separating the organic layer. The aqueous layer was extracted with chloroform and the combined extracts were dried over anhydrous magnesium sulfate and evaporated to dryness under reduced pressure to obtain 15.4 g (6-ethyl-7-methoxy-5-methylimidazo[1,2-a]pyrimidin-2-yl)methanol (93% yield as a white crystalline solid melting at 186-188° C. (decomp.).
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