Knoevenagel Condensation of Aldehydes with Ethyl Cyanoacetate in Water Catalyzed by P4VP/Al₂O₃-SiO₂

Table 7

Knoevenagel condensation reaction of aromatic and aliphatic aldehydes and ethyl cyanoacetate catalyzed by P4VP/Al₂O₃-SiO₂^a.

Entry	SubstrateProduct	Time; (min)^b	Yield^c; (%)
1		30 (I); 75 (II)	98; 98
2		5 (I); 5 (II)	98; 98
3		60 (I); 60 (II)	98; 70
4		30 (I); 60 (II)	98; 90
5		10 (I); 20 (II)	60; 40
6		45 (I); 45 (II)	98; 60
7		5 (I); 5 (II)	98; 98
8		5 (I); 5 (II)	98; 98
9		40 (I); 65 (II)	90; 87
10		45 (I); 75 (II)	93; 93
11		30 (I); 40 (II)	92; 90

^aReaction conditions: catalyst (0.04 g), ethyl cyanoacetate (2 mmol), substrate (2 mmol), H₂O (10 mL), and reflux. ^bFor (I) the solvent was H₂O, and for (II) solvent-free condition was chosen. ^cIsolated yield.