4-Toluenesulfonyl chloride → 7-iodo-5-(toluene-4-sulfonyl)-2-(3,4,5-trimethoxy-phenyl)-5H-pyrrolo[2,3-b]pyrazine

Participants

Reaction Conditions

Reaction Steps

7-Iodo-2-(3,4,5-trimethoxy-phenyl)-5H-pyrrolo[2,3-b]pyrazine (371 mg, 0.9 mmol) was suspended in 5 ml of THF and cooled to 0° C. in an ice bath. Sodium hydride, 60% dispersion in mineral oil (43 mg, 1.08 mmol) was added and the suspension was stirred for 20 minutes. 4-Methyl-benzenesulfonyl chloride (189 mg, 0.99 mmol) was added, the ice bath was removed, and the reaction was stirred at room temperature for 3 hours. The solvent was evaporated on a rotary evaporator. The residue was triturated with 1M potassium hydroxide. The solid was filtered, washed with water, and dried to yield 480 mg of 7-iodo-5-(toluene-4-sulfonyl)-2-(3,4,5-trimethoxy-phenyl)-5H-pyrrolo[2,3-b]pyrazine which was used without further purification.

Provenance & Evidence