Table 1. Effects of Different Catalysts on the Tandem Oxidative Cyclization of Amines and 1,3-Dicarbonyls^a.

entry	catalyst	conv. %b	TONc	TOFd
1	no catalyst	5
2	Fe3O4	10	39	13
3	SiO2@Fe3O4	12	47	16
4	Am-SiO2@Fe3O4	8	31	10
5	Cu@Am-SiO2-Fe3O4	45	177	59
6	Cu-BPy@Am-SiO2@Fe3O4	100	393	131

^aReaction conditions: methylacetoacetate (1 mmol), benzylamine (2 mmol), catalyst (30 mg), H₂O₂ (3 equiv), I₂ (1.2 equiv), dimethylformamide (DMF, 3 mL), r.t., 3 h.

^bConversion percentages were determined via gas chromatography–mass spectrometry (GC–MS).

^cTON is the number of moles of product per mole of catalyst.

^dTOF = TON/h.