A mechanistic investigation of Biginelli reaction under base catalysis

The mechanism of the three component base mediated Biginelli dihydropyrimidines synthesis was investigated using Accurate Mass TOF LC-MS-ESI and Tandem TOF LC-MS-ESI. We suggest hemiaminal as a possible intermediate leading to the formation of Biginelli product. Under our current experimental conditions we did not observe any bis-ureide as reported by ji et al.