Hydrochloric Acid → 3-ethylhexahydro-1-methyl-3-(3-oxo-1-cyclohexen-1-yl)-2H-azepin-2-one

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Reaction Steps

A 2 molar solution of isopropylmagnesium bromide in ether (70 ml) was treated with 3-ethyl-hexahydro-1-methyl-2H-azepin-2-one (21.7 g, Aust. J. Chem. 1976, 29 2651) in THF (20 ml) and the mixture treated dropwise with diisopropylamine (19.6 ml) (exothermic). The reaction mixture was stirred for 2 hours then treated dropwise with 3-methoxy-2-cyclohexenone (12.6 g) in THF (20 ml). After stirring for 2 hours the reaction mixture was poured onto cold 2 N HCl (250 ml). After 10 minutes the mixture was extracted with dichloromethane (2×300 ml), the combined organic phases washed with saturated aqueous NaHCO3 solution and dried (MgSO4). Removal of the solvents under reduced pressure followed by distillation gave the title compound as a viscous oil (Bpt 155°-160° C./0.1 mm) (13 g). Redistillation (154°-158° C./0.07 mm) gave analytically pure material.

Provenance & Evidence