Bis(2-Methoxyethyl)amine → 3-[[Bis(2-methoxyethyl)amino]methyl]-2-(4-methoxyphenylmethyl)-2H-thieno[3,2-e]-1,2-thiazine 1,1-dioxide

Participants

Reaction Steps

To a solution of the product from Step C (1.60 g, 4.75 mmol) and triethylamine (1.44 g, 14.2 mmol) in anhydrous THF (100 mL) at ambient temperature was added methanesulfonic anhydride (1.24 g, 7.13 mmol). After 1 h, the reaction mixture was divided into two equal portions; to one of these portions was added bis(2-methoxyethyl)amine (6 mL). The mixture was stirred for 72 h, evaporated to dryness and the residue extracted with ethyl acetate (2×100 mL). The combined extracts were dried (MgSO4), filtered and evaporated to a residue which was purified by column chromatography (silica, 20-30% ethyl acetate/hexane) to give an oil (0.71 g) which solidified upon standing: mp 75°-77° C.

Provenance & Evidence