Table 2.

Reaction optimization by utilizing different amounts of nanocatalyst.

Entry	Reagent	Condition	R.Wa (g)	Time (h)	Yield (%)
1	TBTUb	DIPEA/dry DCM, r.t./N2	0.64	12	76
2	Fe3O4@SiO2/TABHA	P(OEt)3/DCM, r.t./N2	0.2	4	85
3	Fe3O4@SiO2/TABHA	Dry DCM, r.t./N2	0.2	4	90c
4	Fe3O4@SiO2/TABHA	Dry DCM, r.t./N2	0.2	6	88
5	Fe3O4@SiO2/TABHA	Dry DCM, r.t./N2	0.15	8	84
6	Fe3O4@SiO2/TABHA	Dry DCM, r.t./N2	0.11	10	70

^aReagent weight.

^b O-(benzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium tetrafluoroborate.

^c Optimum conditions.