Bromine → 5-(Benzyloxy)-7-bromobenzo[d]thiazol-2-amine

Participants

Reaction Conditions

Reaction Steps

To an ice-cold suspension of (3-benzyloxy-5-bromo-phenyl)thiourea (372 g, 1.10 mol) in acetonitrile (6 L) was added dropwise a solution of bromine (65 mL 1.26 mol in 50 mL acetonitrile) over a period of 30 min. The reaction mixture was stirred for 30 min at 0-5° C. then slowly allowed to come to rt, whereby a solid precipitated out. The resulting mixture was stirred at rt for 1 h. After completion of reaction (by TLC), the solid was filtered off and washed extensively with hexane (2×3 L). The solid residue was taken up in ice water, basified with aq. NH3 (pH 10-12) and stirred for 30 min at 5-10° C. The resulting solid was filtered off washed with water and dried under high vacuum to obtain the desired product (216 g, 59%). 1H-NMR (DMSO-d6): δ 5.12 (s, 2H), 6.92 (d, J=2.40 Hz, 1H), 6.98 (d, J=2.0 Hz, 1H), 7.30-7.45 (m, 5H) and 7.69 (br s, 2H). LCMS: 334.79 [M+H]+.

Provenance & Evidence