Table 1.

HAP–Cs₂CO₃ catalyzed Knoevenagel condensation between aromatic aldehydes and malononitrile or ethyl cyanoacetate at 80–100 °C with water as solvent.

Productsa	R	X	Time (h)	Yield (%)b	mp (Lit. mp) °C
3a	C6H5	CN	2.5	77	80–81 (81–82) [21]
3b	4-OCH3C6H4	CN	3	74	114–115 (115–118) [21]
3c	4-ClC6H4	CN	2	86	159–162 (160–163) [21]
3d	4-OHC6H4	CN	3.5	68	188–189 (187–188) [21]
3e	3-NO2C6H4	CN	2.5	73	102–104 (103–104) [21]
3f	3-OCH3-4-OHC6H3	CN	2	72	135–137 (135–136) [21]
3g	2-OHC6H4	CN	1.5	75	98–99 (100–101) [21]
3h		CN	2	77	102–104 (102–105) [21]
3i	–CH=CH–C6H4	CN	3	73	125–127 (126–129) [21]
3j	C6H5	COOEt	15	75	49–50 (49–52) [21]
3k	4-ClC6H4	COOEt	13	82	89–90 (90–94) [21]
3l	4-OHC6H4	COOEt	15	80	87–88 (88–90) [21]
3m	3-NO2C6H4	COOEt	17	78	128–130 (128–132) [21]
3n	4-CH3C6H4	COOEt	14	75	91–92 (90–92) [21]
3o	–CH=CH–C6H5	COOEt	17	71	112–114 (114–115) [21]

^aAll the products were characterised by ¹H NMR, IR, mass spectral data and comparison with authentic samples available commercially or prepared according to the reported methods.

^bYields refer to the isolated yields.