Reaction #502092

Reaction equation

4-(3-chlorobenzyl)-4-dimethylaminocyclohexanone

hydroxylamine

→

1-(3-chlorobenzyl)-N,N-dimethylcyclohexane-1,4-diamine

Conditions

Procedure

1.0 g 1-(3-chlorobenzyl)-N,N-dimethylcyclohexane-1,4-diamine, obtained as a cis/trans-mixture from 4-(3-chlorobenzyl)-4-dimethylaminocyclohexanone by reaction with hydroxylamine and reduction of the oxime obtained with lithium aluminium hydride (WO 02090317), dissolved in 5 ml DMF, was added to 0.74 g N-furan-2-yl-methylsuccinic acid at 0° C. and 0.59 ml N,N-diisopropylcarbodiimide followed by 0.5 g 1-hydroxybenzotriazole (HOBt) were added while stirring. After 3 hours in an ice bath, the mixture was stirred overnight at room temperature. For working up, one-molar sodium carbonate solution was added (pH>10) and the crude product (1.75 g) was isolated by extraction with ethyl acetate/THF (V:V=1:1), with subsequent drying over sodium sulphate and evaporation. The main fraction, obtained after column chromatography on silica gel (3.0×20 cm) with 250 ml diethyl ether, diethyl ether/methanol (V:V=4:1) and diethyl ether/methanol (V:V=1:1), of 718 mg was dissolved in 50 ml 2-butanone, 50 ml ethyl acetate and 2 ml methanol and, by adding 29 μl water and 200 μl chlorotrimethylsilane, converted into the corresponding hydrochloride of the N-[4-(3-chlorobenzyl)-4-dimethylaminocyclohexyl]-N′-furan-2-yl-methylsuccinic acid amide (648 mg of white solid, mp. 233-234.5° C.).

Source