1,3-Dibromo-2-propanol → HCID 19830860, compound

Participants

Reaction Conditions

Reaction Steps

2-(3-Bromo-2-hydroxypropylnaphtho[1,8-cd]isothiazole 1,1-dioxide may be prepared in the following manner: a solution of naphtho[18-cd]isothiazole 1,1-dioxide (41 g) in dimethylformamde (1000 cc) is added over 2 hours under a current of argon to a suspension of sodium hydride (9.6 g) in a 50% dispersion in vaseline oil in dimethylformamide (100 cc), maintaining the temperature between 20 and 35° C. The reaction medium is stirred for 30 minutes at a temperature of about 20° C., then 1,3-dibromo-2-hydroxypropane (20.5 cc) in dimethylformamide (500 cc) is added over 10 minutes. Stirring is maintained for 15 hours at a temperature of about 20° C. The reaction mixture is concentrated to dryness at 70° C under reduced pressure (0.5 mm Hg; 0.07 kPa). The residue is purified by chromatography on a silica column, under a current of argon with a mixture of dichloromethane and methanol (95-5 vol) as eluant. 2-(3-Bromo-2-hydroxypropyl)naphtho[1,8-cd]isothiazole 1, -dioxide (62.1 g) is obtained, in the form of a green oil which is used in the crude state in the subsequent synthesis.

Provenance & Evidence