Table 2.

An initial survey of reaction conditions for reaction of indole with benzaldehyde.

Entry	Temperature (°C)	Catalytic amount (mg)	Mole ratio indole:benzaldehyde	Time (min)	Yielda (%)
1	100	10	2:1	10	30
2	120	10	2:1	10	57
3	140	10	2:1	10	62
4	160	10	2:1	3	83
5	160	1	2:1	10	68
6	160	5	2:1	10	80
7	160	10	2:1	10	98
8	160	10	3:1	10	90
9	160	10	4:1	10	90

^aIsolated yield.