Abstract
The catalytic activity of potassium salts of phthalimide (PPI) and succinimide (PSI), as organonucleophilic catalysts, has been investigated for the cyclotrimerization of isocyanates under solvent-free conditions. PPI showed better catalytic activity in comparison with PSI. Diverse and challenging isocyanates afforded the respective symmetrical isocyanurates in good to quantitative yields in an atom economic reaction without any phase transfer catalyst.
Keywords: Isocyanate cyclotrimerization, heterocycles, green chemistry, potassium phthalimide, potassium succinimide, organonucleophilic catalyst