Table 1 Screening of the reaction conditions.^a


Entry	Variation from standard conditions	Yield (%)^b
1	None	80
2	Me₄NI instead of Et₄NI	75
3	ⁿPr₄NI instead of Et₄NI	72
4	ⁿBu₄NI instead of Et₄NI	66
5	ⁿBu₄NBF₄ instead of Et₄NI	0
6	w/o NH₄I	62
7	w/o TFA	45
8	w/o Et₄NI	trace
9	ⁱPrOH instead of ^tBuOH	49
10	MeOH instead of ^tBuOH	0
11	TFE instead of ^tBuOH	0
12	CF (+) \| Ni (-)	78
13	CF (+) \| CF (-)	trace

Bold formatting shows that entry 1 is the optimal reaction condition.
^aReaction conditions. 1a (0.3 mmol), Et₄NI (2.0 equiv.), NH₄I (2.0 equiv.), TFA (3.0 equiv.), ^tBuOH (3.0 mL) and H₂O (1.0 mL) under 50 mA constant in an undivided cell at 50 ^oC for 12 h with carbon felt (CF) as anode and Pt plate as cathode.
^bIsolated yield. TFA = trifluoroacetic acid; TFE = 2,2,2-trifluoroethanol.

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