Exploring the reactivity of L-tellurocystine, Te-protected tellurocysteine conjugates and diorganodiselenides towards hydrogen peroxide: synthesis and molecular structure analysis.

The oxidation reaction of L-tellurocystine, [Te2{CH2CH(NH3+)COO−}2] (4) with H2O2 in the presence of HBr resulted in the formation of cyclic, zwitterionic organotellurolate(IV) species, namely [Te−{CH2CH(NH3+)COO}(Br)3] (5). The H2O2 oxidation of Te-protected tellurocysteine derivatives [RTe{CH2CH(NH2)COOH}] [R = C6H5 (6) and 4-MeC6H4 (7)] in the presence of HCl resulted in the formation of chlorotellurane species [(C6H5)Te{CH2CH(NH3+)COOH}(Cl)2]Cl (8) and [(4-MeC6H5)Te{CH2CH(NH3+)COO}(Cl)]Cl (9), respectively. The oxidation reaction of diorganodiselenides R2Se2 [R = 4-MeC6H4 (10), R = 4-OMeC6H4 (11), R = 3,4-Me2C6H3 (12) and R = 2,4,6-Me3C6H2 (13)] with H2O2 afforded homoleptic diorganoselenones R2SeO2 [R = 4-MeC6H4 (14), R = 4-OMeC6H4 (15), R = 3,4-Me2C6H3 (16) and R = 2,4,6-Me3C6H2 (17)], respectively. The synthesized compounds were thoroughly characterized by multinuclear NMR (1H, 13C, 125Te/77Se), FT-IR spectroscopy, ESI-MS and elemental analysis. The molecular structures of the compounds were determined by single crystal X-ray diffraction studies. [ABSTRACT FROM AUTHOR]