Orange juice-HCl catalyzed efficient green route for Biginelli reaction under solvent free condition by grinding method

Biginelli reaction is one pot multicomponent reaction. A green approach grinding is applied for this multicomponent reaction containing aromatic aldehydes 1, ethyl aceto acetate 2 and urea / thiourea 3 catalyzed by few drops of natural Orange juice and C. HCl as catalyst under solvent free condition at room temperature. The catalyst used is simple, ecofriendly and provides good result. Grinding process is economical, time and energy efficient. Resulted products 3, 4-dihyropyrimidin-2(1H)-ones or thiones 4A-Kwere confirmed by spectral and analytical analysis