1232365-42-2

1-(Boc-amino)-3,3-difluorocyclobutane-1-methanol is used in preparation of Amide derivatives useful in the treatment of HBV infection or HBV-induced diseases.

The general procedure for the synthesis of tert-butyl (3,3-difluoro-1-(hydroxymethyl)cyclobutyl)carbamate from compound BB2-g (CAS: 1232365-41-1, 4 g, 0.0143 mol) was as follows: a 2 M lithium borohydride solution (30 mL) was slowly added to an anhydrous THF (100 mL) solution of compound BB2-g under ice bath cooling. The reaction mixture was then gradually warmed to room temperature. The reaction mixture was stirred continuously for 3 hours at room temperature. Upon completion of the reaction, the reaction was quenched by careful addition of ice water and 5% citric acid solution and then extracted three times with dichloromethane (DCM). The organic phases were combined, dried over anhydrous sodium sulfate (Na2SO4), filtered and concentrated under reduced pressure to afford the target product tert-butyl (3,3-difluoro-1-(hydroxymethyl)cyclobutyl)carbamate (3.1 g, 91% yield).

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