Table 2. Comparative Study of I₂ and HI Mode of Catalysis^a.

entry	catalyst	yield (%)b
1	I2	85
2	I2 + H2Ob	82
3	I2 + KI	43
4	I2 + MS	86
5	HI	26
6	HI + KIc	26

^aReaction conditions: 1-methylindole (1.2 equiv), diphenylmethanol (1 equiv), catalyst (5 mol %), solvent (2 mL), temperature (40 °C), time (5 h), in air.

^b28 mol % water.

^c1 equiv of KI.