Table 1. Optimization of Reaction Conditions^a.

entry	catalyst	cooxidant	t, time	yield of 2, %
1b	Co(OAc)2	AgNO3	80 °C, 16 h	16
2b	Co(acac)2	AgNO3	80 °C, 16 h	66
3	Co(acac)2	none	80 °C, 16 h	15
4c	Co(acac)2	Mn(OAc)2	80 °C, 16 h	41
5c	Co(acac)2	Mn(OAc)3·2H2O	80 °C, 16 h	90
6c	none	Mn(OAc)3·2H2O	80 °C, 16 h	<1
7c,d	Co(acac)2	Mn(OAc)3·2H2O	rt, 16 h	93

^aAmide (0.1 mmol), styrene (0.12 mmol), catalyst (0.02 mmol), base (0.2 mmol), CF₃CH₂OH (1 mL), under air. Yield determined by NMR of crude reaction mixtures; 1,1,2-trichloroethane internal standard.

^bAgNO₃, 2 equiv.

^cMn(OAc)₂ or Mn(OAc)₃·2H₂O, 0.5 equiv.

^dReaction open to air.