Table 1. Optimization of Reaction Conditions^a.

entry	solvent	Ag salt	yield (external)b
1	DCE	AgSbF6	46
2	DCE	none	tracec
3	THF	AgSbF6	46
4	HOAc	AgSbF6	64
5	dioxane	AgSbF6	81
6	dioxane	AgBF4	52
7	dioxane	AgPF6	15
8	dioxane	AgBC24F20	40
9	dioxane	none	0
10	dioxane	AgSbF6	0d

^aConditions: 1 (0.10 mmol), 2 (0.20 mmol) in 0.5 mL of solvent for 24 h.

^bDetermined by ¹H NMR relative to 2,6-dimethoxytoluene as external standard.

^cIn place of (Cp*RhCl₂)₂, Cp*Rh(CH₃CN)₃(SbF₆)₂ was used.

^dNo (Cp*RhCl₂)₂ was added.