Table 2.

Synthesis of 1-aryl 1H- tetrazole derivatives in the presence Fe₃O₄@SiO₂-Im[Br]-SB-Cu (II) catalyst^a.

Entry	R	Product	Time (min)	Yield (%)b	MP found (Lit.) (°C)43
1	H	4a	20	97	64–66 (64–65)
2	2-Cl	4b	30	86	127–130 (127–131)
3	4-Cl	4c	30	95	156–158 (157–158)
4	4-CH3	4d	15	92	92–94 (94–95)
5	4-OCH3	4e	10	92	115–117 (114–115)
6	4-NO2	4f	60	92	200–204 (201–202)
7	2-OH	4g	45	90	205–207 (-)
8	4-OH	4h	15	95	215–218 (-)
9	4-Br	4i	30	90	181–184 (183–185)

^aReaction conditions: Aniline (1.0 mmol), Triethyl orthoformate (1.2 mmol), Sodium azide (1.0 mmol) and Fe₃O₄@SiO₂-Im[Br]-SB-Cu (II) (0.6 mol %) in the water at 40 °C.

^bIsolated yield.