Table 1.

Aza-Friedel–Crafts Alkyl Imine Optimization^a

entry	solvent	ligand	phenol (equiv)	yield (%)	ee (%)
1	CH2Cl2	(R)-Bn-Box	5	19	−43
2	CH2Cl2	(S)-i-Pr-Box	5	23	69
3	CH2Cl2	(S)-t-Bu-Box	5	5	37
4	CH2Cl2	(S)-Ph-Box	5	54	84
5	CH2Cl2		5	28	<5
6	CH2Cl2		5	5	−5
7	CH2Cl2	(4R,5S)-bis-Ph-Box	5	7	91
8	DCE	(S)-i-Pr-Quinox	1.5	57	<5
9	CH2Cl2	(S)-Ph-Box	1.5	38	84
10	xylenes	(S)-Ph-Box	1.5	24	66
11	THF	(S)-Ph-Box	1.5	11	94
12	toluene	(S)-Ph-Box	1.5	16	75
13	DCE	(S)-Ph-Box	1.5	53	94
14	PhCF3	(S)-Ph-Box	1.5	6	63
15	EtOAc	(S)-Ph-Box	1.5	36	94
16b	DCE	(S)-Ph-Box	1.5	66	76
17c	DCE	(S)-Ph-Box	1.5	49	92
18d	DCE	(S)-Ph-Box	1.5	26	83
19e	DCE	(S)-Ph-Box	1.5	39	87
20f	DCE	(S)-Ph-Box	1.5	0	—

^aReaction conditions: imine 2a (0.20 mmol) and phenol 1a (0.30 mmol) and flame-dried 4 Å mol. sieves were added to a solution of Cu(OTf)₂ (0.020 mmol) and ligand (0.030 mmol) in 1 mL of solvent, and the mixture was stirred at rt for 72 h unless otherwise noted.

^bReaction run at 40 °C.

^cReaction performed at 0.3 M with respect to imine.

^dReaction performed for 24 h.

^eReaction performed for 48 h.

^fReaction performed without Cu(OTf)₂.