Acetic Anhydride → 5-[2-(Dimethylamino)ethyl]-2-(4-methoxyphenyl)-4-oxo-2,3,4,5-tetrahydronaphtho[1,2-b][1,4]thiazepin-3-yl acetate

Participants

Reaction Steps

A mixture of 1.1 g of (±)-cis-5-[2-(dimethylamino)ethyl]-2,3-dihydro-3-hydroxy-2-(4-methoxyphenyl)naphtho[1,2-b]-1,4-thiazepin-4(5H)-one hydrochloride and 20 mL of acetic anhydride was heated at 100° for 17 hours. The excess reagent was removed under reduced pressure and the residue was partitioned between dilute sodium hydroxide and ethyl acetate. The ethyl acetate solution was washed with brine, then dried (magnesium sulfate) and removal of the solvent gave 1.1 g (99%) of (±)-cis-3-(acetyloxy)-2,3-dihydro-2-(4-methoxyphenyl)-5-[2-(dimethylamino)ethyl]-naphtho[1,2-b]-1,4-thiazepin-4(5H)-one. A sample was crystallized from ether, mp 122°-124°.

Provenance & Evidence