SYNTHESIS OF NEW MANNICH BASES DERIVED FROM 5-PHENYL-1,3,4-OXADIAZOLE-2-THIONE AND INVESTIGATION OF THE CONFORMATIONAL ISOMERS OF DIMETHYL 5-(5-PHENYL-2- THIOXO-1,3,4-OXADIAZOLE-3-METHYLAMINO)ISOPHTHALATE

摘要

A series of new N-aminomethylation compounds has been obtained from 5-phenyl-1,3,4-oxadiazole-2-thione through reaction with formaldehyde and less common aliphatic and aromatic amines. The conformational isomers of 5-(5-phenyl-2-thioxo-1,3,4-oxadiazole-3-methylamino)isophthalate have been investigated using the STO-2G basis set. Four minimum energy structures have been found on the electronic potential energy surface. The relative stability of conformational isomers and the barrier height for conformational interconversion are presented.