Iodoethane → 3-Ethylhexahydro-3-(3-methoxyphenyl)-1-methyl-2H-azepin-2-one

Participants

Reaction Steps

a solution of butyl lithium (0.05 mole) in hexane (31.25 ml) was treated with 2,2,6,6-tetramethylpiperidine (8.5 ml), followed by dry tetrahydrofuran ("THF"; 100 ml) under an inert atmosphere at 0° C. The mixture was treated with a solution of N-methylcaprolactam (6.25 ml, 50 mM) in THF (20 ml) and stirred for 30 minutes. A solution of butyl lithium (0.05 mole) in hexane (31.25 ml), was added and the mixture stirred for 15 minutes. A solution of o-chloroanisole (6.2 ml) in THF (20 ml) was added slowly, the mixture stirred for 1.5 hours and treated with ethyl iodide (5.15 ml). After one hour, the reaction was quenched with water (100 ml) and the solvents removed under reduced pressure. The residue was partitioned between 2 N HCl (200 ml) and toluene (250 ml). The organic layer was washed with brine, dried and the solvents removed under reduced pressure, to give 3-ethylhexahydro-3-(3 -methoxyphenyl)-1-methyl-2H-azepin-2-one (5.5 g) b.p. 140°/0.1 mm. Recrystallisation from diisopropyl ether gave pure title compound (5.0 g) m.p. 68°-69° C., identical with authentic material.

Provenance & Evidence