Hydrochloric Acid → alpha-methyl-N,N-diethyl-1-phenyl-2,5-cyclohexadien-1-ethylamine hydrochloride

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Reaction Steps

To 27.5 ml. (about 6 equivalents) of diethylamine and 10 g. of molecular sieve 3A in 200 ml. of methanol are added at 0° C. 17.6 ml. of 5 N methanolic hydrochloric acid (2 equivalents) and then 9.4 g. of (1-phenyl-2,5-cyclohexadien-1-yl)-2-propanone in a small amount of methanol and finally 1.95 g. (0.7 equivalents) of sodium cyanoborohydride. The mixture is stirred at room temperature for 5 days and then worked-up in exactly the same manner as described in Example 16. There is obtained an oily residue which is chromatographed on a silica gel thick-layer plate with ethyl acetate/triethylamine (15:1). Two products are scratched off and eluted with methylene chloride/methanol (4:1). The product of RF 0.32 is α-methyl-N-ethyl-1-phenyl-2,5-cyclohexadien-1-ethylamine. The other product (RF 0.54) is the desired product, namely, α-methyl-N,N-diethyl-1-phenyl-2,5-cyclohexadien-1-ethylamine. This is converted as usual into the hydrochloride and recrystallized from methylene chloride/ether. According to melting point and mixed melting point, the product is identical with that obtained in accordance with Example 18.

Provenance & Evidence