Table 4.

Reaction optimization.

entry	equiv PhIO	conc.	mol % cat.a	4a : 4b	total yieldb
1	3.5	0.05 M	10%	2.7 : 1	73%
2	2	0.05 M	10%	2.8 : 1	83%
3	1	0.05 M	10%	2.8 : 1	62% (20%)
4	2	0.1 M	10%	2.9 : 1	80%
5	2 Phl(OAc)2	0.1 M	10%	2.9 : 1	54%
6	2 Phl(OPiv)2	0.1 M	10%	2.7 : 1	51%
7	2	0.2 M	10%	3.4 : 1	82%
8	2	0.4 M	10%	3.2 : 1	80%
9	2	0.2 M	5%	2.6 : 1	65% (8%)
10c	2	0.2 M	5%	3.0 : 1	80%
11c	2	0.2 M	2%	3.0 : 1	79%
12d	2	0.1 M	10%	2.9 : 1	52%
13e	2	0.1 M	10%	2.7 : 1	77%
14f	2	0.1 M	10%	3.2 : 1	75%

^aStandard condition: 10 mol % AgOTf, 12.5 mol % tpa, 3.5 equiv PhIO, 0.05 M H₂O, 40 °C, 30 min.

^bNMR yields based on mesitylene as internal standard, recovered 4 in parentheses.

^cThe reaction was run overnight.

^dpH 2.8 Na₂HPO₄:citric acid hydrate buffer.

^epH 5.0 NaOAc buffer.

^fpH 9.5 Na₂CO₃:NaHCO₃ buffer.