Table 1.

Optimization of the formation of indole 3aa.

Entry	1a:2a Ratio	Base	Additivesc	3aa, yield (%)a	4a, yield (%)a
1b	1:1.5	K2CO3	–	8	10
2c	1:1.5	K2CO3	1 mol% [Ir]	38	18
3	1:1.5	K2CO3	10 mol% PhCOPh	61	16
4	1:1.5	K2CO3	–	64	16
5	1:1.1	K2CO3	–	62	10
6	1:1.1	Na2CO3	–	4	10
7	1:1.1	Cs2CO3	–	10	6
8	1:1.1	CaCO3	–	0	0
9	1:1.1	K2CO3	1 equiv 18-C-6	14	16

^aNMR yield using 1,3,5-trimethoxybenzene as internal standard; all reactions run on a 0.1 mmol except for entries 3 and 4 (0.3 mmol).

^b5 mol% PPh₃AuCl was used instead of 5 mol% [AuCF₃].

^c[Ir] = [Ir[dF(CF₃)ppy]₂(dtbbpy)PF₆].