1248635-79-1

Upstream product

• 1248635-29-1 1,6-dimethyl-5-ethoxycarbonyl-4-(2-(triphenylphosphoranylideneamino)phenyl)-3,4-dihydropyrimidin-2(1H)-one 
• 98-88-4 benzoyl chloride 

Relevant academic research and scientific papers

New efficient synthesis of pyrimido[1,6-c]quinazolin-4-ones by a Biginelli 3CC/Staudinger/aza-Wittig sequence

Dihydropyrimidinone azides 1, obtained from trimethylsilyl chloride-catalyzed Biginelli reaction of 2-azidobenzaldehyde, ethyl acetoacetate, and urea (or thiourea) at room temperature, reacted with triphenylphosphine to give iminophosphorane 2. A tandem aza-Wittig reaction of iminophosphorane 2 with isocyanate, acyl chloride or CS2 in the presence of K2CO3 or NEt3 generated pyrimido[1,6-c]quinazolin-4-ones 4, 6 or 8 in moderate to good yield.