Table 1.

Optimal condition screening.^a,b

Entry	Reaction conditionsa,b	1a convn.	2a
1	5% PPh3AuCl, 5% Phen, 2 eq. PIDA, 50 °C	100%	<10%
2	Entry 1, syringe pump addition of 1a	100%	12%
3	L[AuCl]2 (10%): L= dppm, dppp, BINAP	100%	<10%
4	10% Xantphos[Au2Cl2], cat-1	100%	15%
5	10% t-BuXantphos[Au2Cl2], cat-2	100%	75%
6	Entry 1, [Au]=5% [t-BuXantphosAu]+[BF4]−, cat-3	<5%	n.d.
7	Entry 1, [Au]=5% [(n-Bu)4N]+[Cl-Au-Cl]−; cat-4	100%	75%
8	Entry 7 without PIDA	<5%	n.d.
9	Entry 7 without Phen	<5%	n.d.
10	Glaser cond.: 100% Cu(OAc)2, MeOH/pyridine, 50 °C, 24h	50%	12%
11	Hay cond.: 20% CuCl, 40% TMEDA, iPrOH, O2, 50 °C, 24 h	20%	<10%
12	Collins’ bi-phase condition	100%	60%
13	Other metal catalysts: Rh, Ag, Pt, Ru, Fe, Ni, Pd.	<25%	<5%

^aReaction conditions: 5 mol% catalyst and 5% Phen was added to a MeCN solution (30 mL) of 1a (0.1 mmol) and PIDA (0.2 mmol), and reaction was kept under Ar at 50 °C for 24 h.

^bConversion and yield were determined by 1H NMR spectroscopy using 1,3,5-trimethoxybenzene as internal standard.