Formaldehyde → HCID 11303722, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 1-{2-piperazin-1-yl-1-[3-(trifluoromethoxy)phenyl]ethyl}cyclohexanol (590 mg, 1.59 mmol) (see Example 23), in formic acid (3.1 mL) at 50° C., was treated with an aqueous solution of formaldehyde (37% in water, 1.3 mL, 1.94 mmol). The reaction was heated at 70° C. for 1.5 h, after which time the reaction was poured into water (50 mL) and basified to pH=10 with the addition of a 2 N aqueous solution of sodium hydroxide. The product was then extracted with ethyl acetate (3×20 mL), and the combined organic extracts were dried over magnesium sulfate and concentrated to yield 442 mg (72%) 1-{2-(4-methylpiperazin-1-yl)-1-[3-(trifluoromethoxy)phenyl]ethyl}cyclohexanol as a colorless oil. The product was dissolved in methanol (0.5 mL) and the resulting solution was treated with a saturated methanolic solution of hydrochloric acid (0.5 mL) followed by diethyl ether (2 mL). The solution was stored in the refrigerator for 16 h. The resulting precipitate was filtered and washed with diethyl ether to yield 299 mg (57%) 1-{2-(4-methylpiperazin-1-yl)-1-[3-(trifluoromethoxy)phenyl]ethyl}cyclohexanol dihydrochloride as a white solid. HRMS: calcd for C20H29F3N2O2.2.00 HCl, 458.1715; found (ESI), 387.2263.

Provenance & Evidence