5-(benzyloxyMethyl)-1H-pyrazol-3-aMine synthesis

Yield:393590-62-0 70.4 g

Reaction Conditions:

with hydrazine hydrate monohydrate in ethanol; for 16 h;Reflux;

Steps:

Intermediate XIII-1: 3-(benzyloxymethyl)-1H-pyrazol-5-amine.

To Intermediate XII-1 (about 75.7 g, 0.4 mol) obtained above 500 ml of ethanol and 100 ml (2.1 mol) of hydrazine monohydrate were added. The mixture was refluxed for 16 h. After evaporation of the solvent to dryness under reduced pressure, the residue was added with chloroform and dried over anhydrous sodium sulphate. Drying agent was filtered off and the solvent was evaporated, and the mixture was separated on a chromatographic column using ethyl acetate/methanol from 100/0 to 95/5 as an eluent. After separation, 70.4 g (87%) of Intermediate XIII-1 were obtained as a brown oil. 1H NMR (300 MHz; CDCl3) δ: 7.39 - 7.28 (m; 5H); 5.59 (s; 1H); 4.53 (s; 2H); 4.50 (s; 2H). MS-ESI: (m/z) calculated for C11H13N3O [M+H]⁺: 204.25; determined 204.1.

References:

WO2016/157091,2016,A1 Location in patent:Page/Page column 21