C([O:3][C:4]([C:6]1[C:7]([CH3:12])=[N:8][N:9]([CH3:11])[CH:10]=1)=O)C.CC(C[AlH]CC(C)C)C>O1CCCC1>[CH3:11][N:9]1[CH:10]=[C:6]([CH2:4][OH:3])[C:7]([CH3:12])=[N:8]1To a cooled solution (0° C.) of 1,3-dimethyl-1H-pyrazole-4-carboxylic acid ethyl ester (5.0 g, 29.7 mmol) in anhydrous tetrahydrofuran (1000 ml), is added a solution of DIBAL-H (95.1 ml, 95.1 mmol). The reaction mixture is stirred at 0° C. for 2 hours and then quenched with saturated aqueous sodium potassium tartrate and stirred for 2 hours. The layers are separated and the aqueous layer is extracted with ethyl acetate. The combined organic extracts are dried over anhydrous Na2SO4, filtered, and concentrated in vacuo to give 1,3-dimethyl-1H-pyrazol-4-methanol (3.7 g, 100%) which is used without purification. 1H NMR (CDCl3): δ=7.22 (1H, s), 4.46 (2H, s), 3.74 (3H, s), 2.20 (3H, s).
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