Benzyl Chloride → HCID 19020637, compound

Participants

Reaction Steps

To a stirred mixture of 15.8 parts of a sodium hydride dispersion 50% and 660 parts of dimethyl sulfoxide were added portionwise 78.4 parts of 1-acetyl-4-(6-fluoro-2H-indazol-3-yl)piperidine under nitrogen atmosphere. Upon complete addition, stirring was continued for 1 hour at room temperature. 42 Parts of chloromethylbenzene were added dropwise during 45 minutes. Upon completion, stirring was continued overnight at room temperature. The reaction mixture was poured into crushed ice and the product was extracted with dichloromethane. The extract was dried, filtered and evaporated. The residue was purified by column chromatography (HPLC) over silica gel using a mixture of methylbenzene and methanol (90:10 by volume) as eluent. The first fraction was collected and the eluent was evaporated, yielding 91 parts (86.3%) of 1-acetyl-4-[6-fluoro-2-(phenylmethyl)-2H-indazol-3-yl]piperidine as a residue (int. 1). b) A mixture of 8 parts of 1-acetyl-4-[6-fluoro-2-(phenylmethyl)-2H-indazol-3-yl] piperdine and 70 parts of a hydrochloric acid solution 6N was stirred for 6 hours at reflux temperature. The reaction mixture was evaporated and the oily residue was crystallized from 2-propanol. The product was filtered off and dried, yielding 2 parts (25.1%) of 6-fluoro-2-(phenylmethyl)-3-(4-piperidinyl)-2H-indazole monohydrochloride; mp.>300° C. (int. 2).

Provenance & Evidence