Optimization of the reaction conditions^a.

Entry	Cat	n	Ligand	X	Solvent	T/°C	Yieldb (%)	eec (%)
1	Nd-1	10	H2L1	12	THF	rt	99	31
2	Nd-1	10	H2L2	12	THF	rt	99	23
3	Nd-1	10	H2L3	12	THF	rt	86	31
4	Nd-1	10	H2L4	12	THF	rt	99	27
5	Nd-1	10	H2L5	12	THF	rt	99	30
6	Nd-1	10	H2L6	12	THF	rt	99	27
7	Nd-1	10	H2L7	12	THF	rt	86	11
8	Nd-1	10	H2L8	12	THF	rt	99	13
9	Nd-1	10	H2L9	12	THF	rt	99	23
10	Sm-2	10	H2L1	12	THF	rt	99	33
11	Eu-3	10	H2L1	12	THF	rt	89	35
12	Yb-4	10	H2L1	12	THF	rt	35	4
13	La-5	10	H2L1	12	THF	rt	99	41
14	La-5	10	H2L1	12	Tol	rt	99	5
15	La-5	10	H2L1	12	Hex	rt	87	37
16	La-5	10	H2L1	12	DME	rt	89	35
17	La-5	10	H2L1	12	CH3CN	rt	99	57
18	La-5	10	H2L1	12	CH3CN	0	99	70
19	La-5	10	H2L1	12	CH3CN	-20	99	80
20	La-5	10	H2L1	12	CH3CN	-40	82	56
21	La-5	10	H2L1	15	CH3CN	-20	99	71
22	La-5	10	H2L1	20	CH3CN	-20	99	75
23	La-5	5	H2L1	12	CH3CN	-20	99	57

^aThe reaction was performed with chalcone (0.3 mmol), TBHP (0.36 mmol) in 1 mL of solvent.

^bHPLC yield.

^cDetermined by chiral HPLC analysis.