2-arylimino(diferrocenyl)- and (di-p-anisyl)dihydropyrimidines: Novel synthesis, structures, and electrochemistry

摘要

2,3-Differocenyl- and 2,3-dianisyl-1-methylsulfanylcyclopropenilium iodides react with 1,3-diphenyl- and 1,3-di-o-tolylguanidine to give 1-aryl-2-arylimino-5,6- (5a,5b) and -4,5-diferrocenyl-1,2-dihydropyrimidines (6a,6b) (～2:1) and, respectively, 5,6- and 4,5-dianisyl-3-phenyl-2- phenylimino-1,2-dihydropyrimidines (～2:1). Their structures were established based on the spectroscopic data and X-ray diffraction analysis of 5,6-diferrocenyl-1-(o-tolyl)-2-(o-tolyl)imino- and 4,5-diferrocenyl-1-phenyl-2- phenylimino-1,2-dihydropyrimidines (5b and 6a, respectively). Electrochemical behavior of compounds 5b, 6b, and 5a+6a were investigated using experiments of cyclic voltammetry and chronoamperometry. For all the compounds, two electrochemical processes (I, II), attributed to the oxidations of the ferrocenes moieties were observed. The values of ΔE ~0' (II-I) and comproportionation constant K _(com) are also reported. Additionally, an electrochemical oxidation with a fast coupled chemical reaction related to the pyrimide ring was also detected.