1: With diethylamine in ethanol Gewald reaction; 0.166667 h; Reflux; 2: With sulfur in ethanol Gewald reaction; 3 h; Reflux;

1: anhydrous cyanoacetic acid With 4-(N,N-dimethlyamino)pyridine; poly(ethylene glycol) 3400; dicyclohexyl-carbodiimide 0.0833333 h; microwave irradiation; 2: cyclopentanone With sulfur; N-ethyl-N,N-diisopropylamine Gewald reaction; 0.333333 h; microwave irradiation; 3: methanol With potassium cyanide T=20°C;