Table 1 Optimization of catalyst system for the cross-coupling reaction.

Entry^a	Pd catalyst	Cu catalyst	Yield [%]^b	ee [%]^c
1	L4-Pd	L1-Cu	<5	n.d.
2	L5-Pd	L1-Cu	<5	n.d.
3	L6-Pd	L1-Cu	<5	n.d.
4	L7-Pd	L1-Cu	<5	n.d.
5	L8-Pd	L1-Cu	53	96
6	L9-Pd	L1-Cu	50	98
7	L10-Pd	L1-Cu	73	99
8	L11-Pd	L1-Cu	87	96
9	L11-Pd	L2-Cu	75	98
10	L11-Pd	L3-Cu	86	99
11	ent-L11-Pd	L3-Cu	82	93
12	L11-Pd	—	n.r.	n.d.
13	—	L3-Cu	n.r.	n.d.

n.d. not determined, n.r. no reaction.
^aReaction conditions: (i) 1a (0.2 mmol), 2a (0.1 mmol), Pd catalyst (4 mol%), Cu catalyst (5 mol%), Et₃N (200 mol%), THF (0.5 mL), 30 °C, 24 h; (ii) citric acid (10 wt%, 4 mL).
^bIsolated yields are provided.
^cThe ee values were determined by HPLC using a column with a chiral stationary phase.

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