Table 1. Summary of the effects of reaction parameters on the reaction efficiency^a .

Entry	Variants	Yield (%)	e.e. (%)b
1	none	72 (69)c	92
2	L1	73	52
3	L2	76	42
4	L3	31	36d
5	L4	47	60
6	L5	37	58
7	NiBr2	52	80
8	NiBr2.diglyme	51	84
9	Ni(COD)2	31	80
10e	CsF	70	68
11	PMHS	57	91
12	DMF as solvent	73	66
13	DCE as solvent	n.d.	n.d.

^aSee the Supporting Information for section 2 experimental details; all reactions were carried out in a 0.1 mmol scale with respect to 2a; corrected GC yields using n-dodecane as an internal standard were reported.

^bThe enantiomeric excesses (e.e.s) were determined using HPLC analysis of the corresponding alcohol after stereospecific oxidation of the boronic ester (see Supplementary Information section 2 for full details).

^cIsolated yield is shown in the parenthesis.

^dThe opposite enantiomer was enriched.

^eReaction time = 12h. DMF = Dimethylformamide; DCE = 1,2-Dichloroethane; RT = room temperature; h = hour. n.d. = not detected; PMHS = Polymethylhydrosiloxane; DEMS = Diethoxy-methylsilane.