4-bromo-1,3-dihydro-2-benzothiophene 2,2-dioxide

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 4-Bromo-1,3-dihydrobenzo[c]thiophene 2,2-dioxide (0.1 m) is dissolved in dry quinoline. To the quinoline solution is added (0.1 M) of cuprous cyanide. The temperature of the mixture is maintained between 100°-160° C. for about 6 to 12 hours. At the end of this time the mixture is poured into water and concentrated ammonium hydroxide. Benzene is added and the mixture is stirred until the solids are dissolved. Ethyl ether is added and the mixture is filtered to remove undissolved solids. The organic and aqueous phases are separated and the aqueous phase is discarded. The organic phase is then washed with 6 N ammonium hydroxide, 6 N hydrochloric acid and saturated sodium chloride. Removal of the benzene-ethyl ether gives the title compound which is used without further purification. The temperature of the mixture is maintained between 100°-160° C. for about 6 to 12 hours are dissolved the mixture is filtered to remove undissolved solids The organic and aqueous phases are separated The organic phase is then washed with 6 N ammonium hydroxide, 6 N hydrochloric acid and saturated sodium chloride Removal of the benzene-ethyl ether

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 1,3-Dihydrobenzo[c]thiophene 2,2-dioxide [Chem. & Ind., 1024 (1965)] is brominated according to the method described in Khim. Tadzh., 107 (1973), [C.A., 84, 89,930 (1976)], using bromine (1.1 equivalents) in refluxing carbon tetrachloride which contains iron until the bromine color is dissipated. Removal of the carbon tetrachloride and recrystallization from ethanol gives 4-bromo-1,3-dihydrobenzo[c]thiophene 2,2-dioxide. Removal of the carbon tetrachloride and recrystallization from ethanol

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 1,3-Dihydrobenzo[c]thiophene 2,2-dioxide, previously described, is brominated with 1 equivalent of bromine in carbon tetrachloride solution in the presence of iron [CA 84, 89930 (1976)] at reflux until the bromine color disappears to give 4-bromo-1,3-dihydrobenzo[c]thiophene 2,2-dioxide.