2-Thiophenesulfonyl chloride → HCID 54248503, compound

Participants

Reaction Steps

A mixture of 4.24 g (26.0 mmol) of 2-amino-5,7-dimethyl-1,2,4-triazolo(1,5-a)pyrimidine, 5.08 g (27.8 mmol) of 2-thiophene sulfonyl chloride and 0.16 g (1.3 mmol) of 4-dimethylaminopyridine in 30 ml of dry pyridine was heated at reflux for 47 hours. The majority of the pyridine was removed by evaporation at reduced pressure and the residue was taken up in 1N NaOH, treated with charcoal and filtered through celite. The filtrated was treated with charcoal and filtered through celite. The yellow filtrate was cooled in an ice bath and acidified with concentrated HCl to precipitate a yellow solid. Drying in vacuo gave 0.50 g (6 percent) of the desired sulfonamide as a yellow powder, m.p. 236°-237.5° C.: IR (KBr) 3390 (broad), 1493, 1375 and 1156 cm-1 ; 'H NMR (DMSO-d6) δ12.3 (1H, broad, --SO2NH--), 7.7-8.1 (2H, m, thiophene H's at 3- and 5-positions), 6.9-7.3 (2H, m including S at 7.03, thiophene H at 4-position and pyrimidine H), 2.62 (3H, s, --CH3) and 2.49 (3H, s, --CH3).

Provenance & Evidence