초록 |
Cr(VI)-heterocyclic complex[Cr(VI)-6-methylquinoline, Cr(VI)-pyrazine] was synthesized by the reaction of heterocyclic compound(6-methylquinoline, pyrazine) with chromium(VI)trioxide. The structure was characterized by IR and ICP analysis. In the presence of H2SO4 solution, Cr(VI)-6-methyl- quinoline, Cr(VI)-pyrazine effectively oxidized benzyl alcohols(H) and its derivatives(p-OCH3, m-CH3, m-OCH3, m-Cl, m-NO2) in N,N'-dimethylformamide. Electron-donating substituents accelerated the reaction, whereas electron acceptor groups retarded the reaction. The Hammett reaction constant(ρ) was Cr(VI)-6-methylquinoline=-0.69(308K), Cr(VI)-pyrazine=-0.70(308K). The obse- rved experimental data was used to rationalized the hydride ion transfer in the rate-determining step. |