Table 1.

Some properties of the compounds 6a–q

Compounda,b	R	R1	R2	Time (hours)	Yield (%)c	Melting point (°C)	Molecular formula	Molecular weight	Rfd
6a	H	H	H	4	74	240	C22H23N3O4	393.44	0.7
6b	H	H	CH3	6	72	237	C23H25N3O4	407.46	0.7
6c	H	5-Cl	H	6	87	255	C22H22N3O4Cl	427.88	0.6
6d	H	5-Br	H	6	56	260	C22H22N3O4Br	472.33	0.4
6e	H	6-Cl	H	5	57	290	C22H22N3O4Cl	427.88	0.5
6f	H	5-F	H	4	51	290	C22H22N3O4F	411.43	0.4
6g	H	5-Cl	CH3	5	59	257	C23H24N3O4Cl	441.91	0.5
6h	CH3	H	H	3	58	256	C23H25N3O4	407.46	0.6
6i	CH3	5-Br	H	5	51	290	C23H24N3O4Br	486.36	0.6
6j	CH3	5-F	H	5	66	<300	C23H24N3O4F	425.45	0.5
6k	CH3	6-Cl	H	5	52	270	C23H24N3O4Cl	441.91	0.5
6l	C6H5	H	H	12	74	258	C29H29N3O4	483.56	0.7
6m	C6H5	H	CH3	12	92	170	C31H33N3O4	511.61	0.6
6n	C6H5	5-Br	H	12	68	270	C29H28N3O4Br	562.45	0.6
6o	C6H5	5-F	H	12	85	<300	C29H28N3O4F	501.55	0.6
6p	C6H5	5-Cl	CH3	12	81	220	C30H30N3O4Cl	532.03	0.7
6q	C6H5	5-Cl	H	12	94	280	C29H28N3O4Cl	518.00	0.6

Notes:

^aReagents and conditions: 5a–q (0.001 mol), 4a–c (0.001 mol), and acetic acid (10 mL).

^bRatio of the product was determined by the analysis of crude FTIR, ¹H-NMR, ¹³C-NMR, and mass spectra.

^cYield refers to pure products after recrystallization.

^dRf studied in EtOAc/hexane (40:60). R = hydrogen, methyl, and benzyl; R¹ = hydrogen and halogen; and R² = hydrogen and methyl.

Abbreviations: EtOAc, ethyl acetate; FTIR, Fourier transform infrared spectroscopy; NMR, nuclear magnetic resonance; Rf, retention factor.