Sodium Iodide → 1-Benzyl-2-[(3,4-dichlorophenyl)dimethylaminomethyl]cyclohexanol, hydrochloride

Participants

Reaction Conditions

Reaction Steps

2-[(3,4-dichlorophenyl)dimethylaminomethyl]cyclohexanone 7.92 g (97.1 mmole) of freshly dried dimethylamine hydrochloride were added while stirring to 214 ml (214 mmole) of sodium iodide solution (1 M in acetonitrile) cooled to 0° C. with an ice bath, followed by the dropwise addition of 27 ml (194 mmole) of triethylamine and 27 ml (214 mmole) of chlorotrimethylsilane, and the whole was stirred for a further hour at RT. 17.0 g (97.1 mmole) of 3,4-dichlorobenzaldehyde were added while cooling with ice, and the whole was stirred for a further hour at RT. The reaction mixture was cooled again to 0° C. with an ice bath, following which 14.7 g (97.1 mmole) of 1-(pyrrolidino)-1-cyclohexene were added, and the whole was stirred for a further two hours at RT. The reaction mixture was worked up by adding 130 ml of semi-concentrated hydrochloric acid, stirred for 10 minutes, washed twice with in each case 125 ml of ether, and adjusted in the alkaline range (pH ca. 9) with 300 ml of dilute ammonia solution (5 vol. %). The reaction mixture was extracted three times with 125 ml of ether each time, and the combined organic extracts were dried over sodium sulfate, filtered, and concentrated by evaporation on a rotary evaporator (500 to 10 mbar) without heating. 26.6 g of crude base (91% of theory) were obtained in this way. 26.7 g of the hydrochloride of 2-[(3,4-dichlorophenyl)dimethylaminomethyl]cyclohexanone (81.8% of theory) were obtained from the crude base according to the procedure described in Example 1 (2nd stage) with chlorotrimethylsilane/water in 2-butanone.

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