Table 3. Comparison of catalysts in C–H insertion and aromatic cycloaddition reactions of 1c and 6c ^a .

Entry	Catalyst	Reactant	t (hours)	2c : 3c	Yield d (%) 2c + 3c	ee e (%) 3c
1 b	AgSbF6	1c	12	>95 : 5	87	—
2 b	Cu(MeCN)4PF6	1c	12	85 : 15	85	—
3 c	Cu(MeCN)4PF6/(S)-t-BuBox	1c	48	<5 : 95	10	28
4 b	Cu(MeCN)4PF6	6c	12	75 : 25	87	—
5 c	Cu(MeCN)4PF6/(S)-t-BuBox	6c	12	<5 : 95	89	30
6 b	AgSbF6	6c	12	85 : 15	82	—
7 c	AgSbF6/(S)-t-BuBox	6c	12	75 : 25	91	24
8	Sc(OTf)3	6c	12	—	NR f	—
9	La(OTf)3	6c	12	—	NR f	—
10	BF3·Et2O	6c	12	—	NR f	—
11 g	(—)	6c	12	—	NR f	—

^aReactions were carried out on a 0.2 mmol scale in 1.0 mL DCM.

^bReactions were carried out with 10 mol% Lewis acid catalyst.

^cReactions were carried out with 10 mol% Lewis acid catalyst and 12 mol% ligand.

^dIsolated yield.

^eThe enantioselectivity was determined by chiral HPLC analysis, see ESI for details.

^fNeither 2c nor 3c was observed, and only slowly decomposition of 6c was observed.

^gThe reaction was carried out in 70 °C.