Table 1.

Reactivity and selectivity of 1 and 1·Mb in the sulfoxidation of thioanisole at pH= 7.^a

Entry	Cat.	Bufferb	Yieldc (%)		Sulfoxide: Sulfone
			Sulfoxide	Sulfone
1	1	Mes	21.0±1.3	1.6±0.1	13.1: 1
2	1	Hepes	18.8±2.0	1.2±0.1	15.6: 1
3	1	His	32.4±1.1	2.8±0.5	11.6: 1
4	1	KPi	39.2±1.9	4.3±0.7	9.1: 1
5	1·Mb	Mes	52.4±2.6	0d	100: 0
6	1·Mb	Hepes	49.4±1.8	0d	100: 0
7	1·Mb	His	44.7±2.9	0d	100: 0
8	1·Mb	KPi	48.6±3.2	0d	100: 0

^aReactions were performed with 5 mM substrate, 10 mM H₂O₂, and 0.5 mM catalyst in 200 μL buffer (50 mM, pH= 7, 5% MeOH) at 4°C for 10 min.

^bBuffers: Mes= 2-morpholinoethanesulfonic acid; Hepes= N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid; Tris= tris(hydroxymethyl)aminomethane; His= histidine; KPi= potassium phosphate.

^cYields were determined by GC with a chiral G-TA column with acetophenone as an internal standard and standard deviation as reported in parentheses.

^dSulfone was not detected.