Formaldehyde → Benzyl 7-methoxy-2,3-dihydrobenzo[f][1,4]thiazepine-4(5H)-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of compound 2 (7.3 g, 23 mmol), paraformaldehyde (6.9 g 0.23 mol) and p-toluenesulfonic acid (1.45 g, 7.6 mmol) in 250 mL of toluene was stirred at 70° C. overnight. After cooling to r.t., the solid was filtered off. The solution was extracted with sat. sodium carbonate (100 mL), and the organic layer was dried over anhydrous sodium sulfate. The target product (7.4 g) was obtained as a liquid after removal of the solvent in 97% yield.

Provenance & Evidence