Indole → 3-Phenylthioindole

Participants

Reaction Conditions

Reaction Steps

A solution of methyl phenyl sulfoxide (4.0 g, 147 mmol) in CH2Cl2 is cooled to −78° C., treated dropwise with trifluoroacetic anhydride (4.0 mL, 5.99 g, 28.5 mmol), stirred for 30 min at −78° C., treated with a solution of indole (1.82 g, 15.6 mmol) in CH2Cl2, stirred for 30 min at −78° C., treated with triethylamine (20 mL, 145 mmol), stirred for 4 days at ambient temperatures and diluted with water. The phases are separated. The organic phase is dried over MgSO4 and concentrated in vacuo. The resultant residue is chromatographed (1:99 methanol:CH2Cl2) to give the title product as a white solid, 3.08 g (88% yield), mp 149-151° C., characterized by mass spectral and HNMR analyses.

Provenance & Evidence