Table 1. Optimization of the Reaction Conditions^a.

entry	R1	R2	cat.	solvent	yieldb	e.r.c
1	Bn	Bn	A	CH2Cl2	traces	–
2	Me	Bn	A	CH2Cl2	traces	–
3	Me	Bzh	A	CH2Cl2	14%	55:45
4	Me	Bzh	B	CH2Cl2	20%	55:45
5	Me	Bzh	C	CH2Cl2	20%	75:25
6	Me	Bzh	D	CH2Cl2	45%	74:26
7	Me	Bzh	D	CHCl3	56%	67:33
8	Me	Bzh	D	1,2-DFB	47%	79:21
9	Me	Bzh	D	1,2-DCE	51%	81:19
10	Et	Bzh	D	1,2-DCE	40%	96:4
11d,e	Et	Bzh	D	1,2-DCE	93%	96:4
12	Bn	Bzh	D	1,2-DCE	>95%	96:4
13d,f	Bn	Bzh	D	1,2-DCE	98%	96:4

^aReaction conditions: 0.05 mmol of 1, 0.25 M, 10 mol% cat., stirring at 900 rpm, 24 h.

^bDetermined by ¹⁹F NMR spectroscopy with 4-fluoroanisole as an internal standard.

^cEnantiomeric ratios were determined by HPLC using a chiral stationary phase.

^dYield of isolated product.

^e72 h, 10 mol% cat.

^f48 h, 5 mol% cat.