Table 1 Representative reaction optimization^a


Entry	Variation from the optimal conditions	Yield of 3 (%)
1	Without 2a	1a’ decomp.
2	None	73
3	MeOH/MeCN (3:1) as solvent	60
4	MeOH/THF (3:1) as solvent	69
5	MeOH as solvent	68
6	CPME as solvent	<1
7	(+)C\|Pt(−) as electrode	58
8	(+)GF\|GF(−) as electrode	52
9	PhSO₂Li, PhSO₂K, PhSO₂Cs, or PhSO₂NⁿBu₄ instead of PhSO₂Na	55, 64, 63, 66
10	PhSO₂NHNH₂ instead of PhSO₂Na	40
11	PhSO₂H (3 equiv.) + Na₂CO₃ (1.5 equiv.) instead of PhSO₂Na	24
12	3 mA	22
13	7 mA	37
14	Under air	46
15	No electrolyte	45
16	No electricity	<1
17	BQ, K₂S₂O₈, or I₂ (2 equiv.) instead of electricity	<1, <1, 8
18	Ag₂CO₃, Cu(OAc)₂ or Mn(OAc)₃·2H₂O (2 equiv.) instead of electricity	<1, 15, 20

CPME cyclopentyl methyl ether, THF tetrahydrofuran, C graphite phate, BQ 1,4-benzoquinone.
^aConditions: 1a’ (0.15 mmol), 2a (0.45 mmol), ⁿBu₄NBF₄ (0.15 mmol), MeOH/CPME (3:1, 2 mL), undivided cell with graphite felt (GF) anode (10 mm × 20 mm × 2 mm) and platinum plate (Pt) cathode (10 mm × 20 mm × 0.3 mm), constant current of 5 mA (ca. 1.9 F^.mol⁻¹), room temperature (25 °C), 1.5 h, under N₂; then hydrolysis with 6 mol/L HCl (5 mL) in MeCN at 60 °C for 24 h. Isolated yields.

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