Hydrochloric Acid → HCID 13854087, compound

Participants

Reaction Steps

319 ml of a 4N solution of hydrogen chloride in dioxane were added to 102 g of 6(R)-t-butoxycarbonylamino-5-oxo-2-(2-thienyl)perhydro-1,4-thiazepine [prepared as described in step (c) above], and the mixture was stirred for 1 hour, with ice-cooling. 500 ml of diethyl ether were then added and the resulting crystals (a yield of 82.3 g) were collected. These crystals were suspended in a mixture of 2 liters of methylene chloride and 0.1 liter of methanol, and a solution of 70 g of potassium carbonate in 200 ml of water was added to the suspension, and the mixture was then stirred for 2 hours. The resulting precipitate was filtered off, and the organic layer was separated from the aqueous layer. The precipitate was dissolved in 200 ml of water, and this solution was combined with the aqueous layer; the mixture was extracted twice, each time with 220 ml of 10% v/v methanol in methylene chloride. The organic layer and the extracts were combined and dried over anhydrous magnesium sulfate, after which sufficient solvent was evaporated off to reduce the volume to about 300 ml. 500 ml of ethyl acetate were added to the residue, and then sufficient of the solvent was evaporated off to reduce the volume to about 400 ml. The residue was left standing at room temperature overnight, and then the precipitated crystals were collected by filtration, to give 19.1 of the title compound, melting at 157° C.

Provenance & Evidence