Table 1.

Reaction conditions screening^a,b

Entry	Reaction conditions varies from standard	Yield of 3
1	None	95%
2	PPh3Au(TA-Me)OTf	6%
3	(ArO)3PAu(TA-Me)OTf	n.r.
4	XPhosAu(TA-Me)OTf	85%
5	JohnPhosAuNTf2, no Zn(OTf)2	30%
6	JohnPhosAuNTf2	60%
7	JohnPhosAuCl	40%
8	No Zn(OTf)2	39%
9	Cu(OTf)2 as Lewis acid	60%
10	Ga(OTf)3, Yb(OTf)3, or In(OTf)3 as Lewis acid	40–42%
11	Zn(NTf2)2 instead of Zn(OTf)2	70%
12	Zn(OAc)2 instead of Zn(OTf)2	45%
13	Dioxane as solvent	85%
14	0.5 M	85%
15	at 100 °C	87%
16	No gold	n.r

^aGeneral reaction conditions: 1 (0.2 mmol, 1.0 equiv.), 2 (0.4 mmol, 2.0 equiv.), [Au] catal. (0.01 mmol, 5 mol%), Lewis Acid (0.02 mmol, 10 mol%) in dry solvent (0.2 mL) under Ar at 110 °C.

^bYield was determined by ¹H NMR using 1,3,5-trimethoxybenzene as an internal standard.