Table 1.

Optimisation of the reaction conditions^a.

Entry	1:2:Oxidant	Oxidant	Solvent	T (°C)	Yieldb
1c	20:1:2	TBHP	–	rt	N.D.
2	2:1:2	TBHP	H2O	rt	N.D.
3c	20:1:2	PhI(OCOCF3)2	–	rt	trace
4c	20:1:2	H2O2	–	rt	N.D.
5c	20:1:2	PhI(OAc)2	–	rt	40
6	2:1:2	PhI(OAc)2	CHCl3	rt	39
7	2:1:2	PhI(OAc)2	H2O	rt	16
8	2:1:2	PhI(OAc)2	DMA	rt	N.D.
9	2:1:2	PhI(OAc)2	DCE	rt	43
10	2:1:2	PhI(OAc)2	MeCN	rt	46
11	2:1:2	PhI(OAc)2	EA	rt	32
12	2:1:2	PhI(OAc)2	C6H5Cl	rt	42
13	2:1:2	PhI(OAc)2	DCM	rt	61
14	2:1:2	PhI(OAc)2	PhH	rt	66
15	2:1:2	PhI(OCOCF3)2	DCM	rt	42
16	2:1:2	PhI(OCOCF3)2	PhH	rt	49
17	2:1:2	PhI(OAc)2	DCM	0	25
18d	2:1:2	PhI(OAc)2	DCM	60	54

^aGeneral procedure: the reaction was carried out with NHPI (1 mmol), cyclohexane (2 mmol), oxidant (2 mmol), and solvent (2 mL) at room temperature for 2 h.

^bIsolated yield.

^cCyclohexane (20 mmol) was used as the substrate and solvent.

^dThe reaction was conducted in reflux.