Table 2.

Synthesis of imidazole derivatives 5a–k from three-component condensation of benzoin (2), aldehyde derivatives 3a–k, and ammonium acetate (4) in the presence of LDH–APS–PEI–DTPA nanocomposite (1).

Entry	Product	Aldehyde	Time (min)	Yield (%)	Melting point (°C)
					Observed	Reported
1			50	97	273–271	272–27348
2			60	98	261–263	260–26249
3			65	95	198–200	197–19950
4			65	95	176–178	177–17850
5			75	70	300–297	301–30250
6			90	70	200–201	200–20251
7			55	85	233–235	232–23550
8			55	90	227–229	227–22850
9			75	80	255–258	256–25751
10			60	90	250–252	250–25151
11			60	85	255–258	256–25848

Reaction conditions: Benzoin (2, 1 mmol), benzaldehyde (3a–k, 1 mmol), and ammonium acetate (4, 2.5 mmol) in the presence of 5 mg LDH–APS–PEI–DTPA nanocomposite (1) in EtOH under reflux conditions.