Reaction of isocyanates with schiff bases

Abstract

1. Electron-donor substituents in the p-positions of the aromatic rings in Schiff bases increase the overall addition rate of the benzoyl and trichloroacetyl isocyanates to Schiff bases and shift the reaction toward the formation of 4-membered rings, whereas electron-acceptor substituents shift the reaction toward the formation of oxidiazinone derivatives. 2. Highly polar solvents (dimethyl sulfoxide and SO2) promote the formation of hexahydro-S-triazine-dione derivatives. © 1973 Consultants Bureau.