p-Toluenesulfonic acid → HCID 18403976, compound

Participants

Reaction Conditions

Reaction Steps

A solution of crude compound 4 (6.5 g, 20 mmol) and p-toluenesulfonic acid (6.0 g, 30 mmol) in THF (150 mL) was heated under reflux for 4 h and then cooled to 0° C., the precipitate of 6 was filtered off and crystallized from methanol: yield 8.0 g (93%); mp 223-225° C.; 1H NMR (DMSO-d6) δ2.28 (s, 3), 7.10 (d, J=8 Hz, 2 H), 7.28 (s, 1 H), 7.50 (d, J=8 Hz, 2 H), 7.71 (m, 3 H), 8.0-8.215 (m, 6 H), 8.33 (d, J=8 Hz, 1 H), 8.61 (s, 1 H). Anal. Calcd for C26H21NO4S: C, 70.40; H, 4.77; N, 3.16. Found: C, 70.38; H, 4.73; N, 3.11.

Provenance & Evidence