Syntheses and Electrochemical Studies of Bis(eta5-Cyclopentadienyl)-(2,3-Quinoxalinedithiolato)Titanium(IV) Derivatives: Comparison with the Electrochemical Properties of Similar Complexes

Abstract

Neste trabalho descreve-se a síntese de novos derivados bis(η 5 -ciclopentadienil)(2,3-quinoxalina-ditiolato)titanio(IV) e bis(η 5 -ciclopentadienil)(1-fenil)(2-metil)(1,2-etenoditiolato)titanio(IV). As propriedades redox destes compostos juntamente com as propriedades de bis(η 5 -ciclopentadienil)(ene-1,2-ditiolato)titanio(IV) similares foram medidas em soluções neutras. Todos os compostos exibiram uma redução reversível envolvendo um elétron, sendo que o potencial de redução é dependente da natureza do ligante ditiolato. Um segundo processo de redução é observado para os derivados de 2,3-quinoxalina. As propriedades destes últimos também foram estudadas em meio ácido e a presença de H + tem um pequeno efeito em ambos os processos, sugerindo que o mesmo tipo de evento ocorre sob as duas condições.In this work the syntheses of novel bis(η 5 -cyclopentadienyl)(2,3-quinoxaline-dithiolato)titanium(IV) derivatives and bis(η 5 -cyclopentadienyl)(1-phenyl)(2-methyl)(1,2-ethenedithiolato)titanium(IV) is described. The redox properties of these compounds along with the properties of similar bis(η 5 -cyclopentadienyl)(ene-1,2-dithiolato)titanium(IV) complexes are assessed in neutral solutions. All the compounds exhibited a reversible one electron reduction process, the potential at which the reduction occurs being dependent on the nature of the dithiolato ligand. A second reduction process is observed on the 2,3-quinoxaline derivatives. The properties of the latter are also assessed in acidic solution and the presence of H + has a small effect on both processes, suggesting that the same type of event occurs under both conditions.

Synthesis and coordination behaviour of 1H-1,2,3-triazole-4,5-dithiolates

“…S30†) falls between that of [Cp 2 Ti{S 2 C 2 (CO 2 Me) 2 }] and [Cp 2 Ti(bdt)]. 37,41 In addition, this trend is reflected by the folding angle and the inversion barrier of those complexes (Table 2). 37,42…”

“…S30 †) falls between that of [Cp 2 Ti{S 2 C 2 (CO 2 Me) 2 }] and [Cp 2 Ti(bdt)]. 37,41 In addition, this trend is reflected by the folding angle and the inversion barrier of those complexes (Table 2). 37,42 Consequently, the new ligand tazdt 2− is somewhat less electron-rich and a slightly weaker donor than benzene dithiolate.…”