Triethylamine → 2,2-Dioxo-6-(1,1-dimethylethyl)-8-iodo-1,2,3-benzoxathiazine

Participants

Reaction Conditions

Reaction Steps

To a solution of sulfamoyl chloride (13.8 g, 0.12 mole) in anhydrous methylene chloride (75 ml) is added a solution of 3-iodo-5-(1,1-dimethylethyl)salicylaldehyde (6 g., 0.02 mole) and triethylamine (12.1 g, 0.12 mole) in anhydrous methylene chloride (100 ml.) dropwise with stirring at 20° C. Upon completing the addition, the resulting reaction mixture is stirred at 20° C. for 3 days. Removal of the solvent in vacuo leaves a tacky residue which is partitioned between ether and 2 N hydrochloric acid. After separating the phases, the organic phase is washed with water and saturated bromine, dried over sodium sulfate and filtered. Evaporation of the filtrate leaves an oily residue (6 g.) which is chromatographed on silica gel (300 g.) with benzene. Elution with benzene (840 ml.) gives recovered 3-iodo-5-(1,1-dimethylethyl)salicylaldehyde (2.2 g., 37% recovery), m.p. 76°-78° C. Continued elution with benzene (500 ml.) provides an impure solid (2.4 g.) which is triturated with hexane (20 ml.) and filtered to afford the title compound as a pale yellow solid (1.0 g, 14%), m.p. 130°-134° C. Crystallization from hexane-benzene (9.1; viv) gives an analytical sample of 2,2-dioxo-6-(1,1-dimethylethyl)-8-iodo-1,2,3-benzoxathiazine, m.p. 135°-136° C.

Provenance & Evidence