Efficient and Convenient Synthesis of 1,8-Dioxodecahydroacridine Derivatives Using Cu-Doped ZnO Nanocrystalline Powder as a Catalyst under Solvent-Free Conditions

Table 3

Synthesis of N-substituted decahydroacridine-1,8-diones using Cu-doped ZnO nanocrystalline powder (10 mol%) as a catalyst in solvent-free condition^a.

Entry	Amines	Aldehydes	Product^b	Time (h)	Yields (%)^c	References
1			4a	1.5	90	[18]
2			4b	2	85	[44]
3			4c	1.5	95	[45]
4			4d	1.5	90	[46]
5			4e	1.5	89	[47]
6			4f	1.5	91	[48]
7			4g	1.5	94	[49]
8			4h	2	90	[18]
9			4i	1.5	93	[18]
10			4j	1.5	95	[49]
11			4k	1.5	92	[48]
12			4l	1.5	85	[50]
13			4m	2	80	[51]
14			4n	2	87	[52]
15			4o	2	83	[19]
16			4p	1.5	88	[44]
17			4q	1.5	90	[52]
18			4r	1.5	89	[53]

^aReactions were carried out with dimedone, amine, and benzaldehyde in 2 : 1 : 1 molar ratio.
^bproducts were characterized with ¹H, ¹³C-NMR, mp.
^cYields refer to isolated pure products.