Hypervalent Tellurium Research Articles

Preparation and X-ray Structure Analysis of 1,1,5,5,9,9-Hexachloro-1,5,9-tritelluracyclododecane (Cl6([12]aneTe3)) and Its Redox Behavior

The first synthesis and structure determination of 1,1,5,5,9,9-hexachlorotritelluracyclododecane (1), a monocyclic multitellurium moiety which is composed of three hypervalent tellurium(IV) atoms, along with redox studies were presented. The pyrolysis of ditellurane (2) in dimethylformamide at 160 °C afforded the ring-expansion products 1, Cl6([12]aneTe3), in 44% yield. The structure of 1 was determined by X-ray diffraction analysis. Each tellurium atom is involved in four bonding contacts, and with the lone pair of electrons the central atoms exhibit a trigonal bipyramidal geometry (TBP). The more electronegative chloride atoms are located in the apical positions, while the lone pair and the two alkyl carbons are in the equatorial position. Compound 1 (1 equiv) reacted with thiophenol (6 equiv) in the presence of triethylamine in dimethyl sulfoxide (DMSO) under an Ar atmosphere at 50 °C for 10 min to give neutral 1,5,9-tritelluradodecane (3), [12]aneTe3, in 90% yield. Compound 3 reacted with Cl2 in CH2Cl2 at room temperature to afford the tris(tellurane) 1 in quantitative yield. The results described herein show a new type of chlorine adduct of a telluromacrocycle, as organotellurium compounds consisting of three hypervalent telluriums are hitherto unknown.

Low‐temperature 1H, 13C, 77Se, and 125Te NMR studies on the apical‐apical ligand exchange via the hypervalent tellurium and selenium ate complexes [10‐M‐3(C3); M = Se, Te] in the reactions of diaryl tellurides and selenides with aryllithium reagents

AbstractPentafluorophenyl phenyl telluride (1) and 3,5‐dichloro‐2,4,6‐trifluorophenyl phenyl telluride (2) react with pentafluorophenyllithium or 3,5‐dichloro‐2,4,6‐trifluorophenyllithium in THF at low temperatures to form the corresponding tellurium ate complexes (A) and (B) as sole intermediates in the ligand exchange on the hypervalent tellurium atom. The corresponding selenides (3) and (4) also react with identical aryllithium reagents in THF to form the discrete intermediates, selenium ate complexes (C) and (D), in the exchange reactions. In these ligand exchange reactions of tellurides and selenides, electron‐withdrawing ligands occupy the apical positions and the exchange takes place between these apical‐oriented groups. The low‐temperature 1H, 13C, 77Se, and 125Te NMR spectroscopic techniques are effective methods for detection of unstable tellurium and selenium ate complexes.

First Crucial Evidence for Apical-Apical Exchange via a Hypervalent Tellurium Ate Complex in the Reactions of Diaryl Tellurides with Aryllithium Reagents

Abstract Pentafluorophenyl phenyl telluride and 3,5-dichloro-2,4,6-trifluorophenyl phenyl telluride reacted with pentafluorophenyllithium or 3,5-dichloro-2,4,6-trifluorophenyllithium at low temperature to form the corresponding tellurium ate complexes as sole intermediates of the ligand exchange on the hypervalent tellurium centers. In these tellurium ate complexes electron-withdrawing aryl ligands were arranged at apical positions and the ligand exchanges took place between the apical-directing groups.

Generation and Reactions of Hypervalent Organic Selenium and Tellurium Compounds Having Aryl Ligands

Abstract The evidence for the formation of tetraaryl selenuranes as intermediates was presented in the ligand coupling reaction of triaryl-selenonium or diaryl selenoxide with phenyllithium (PhLi) by NMR studies. Triaryl telluranes were also formed as intermediates in the ligand exchange and disproportionation reactions of diaryl tellurides with PhLi.

ChemInform Abstract: Hypervalent Tellurium in One‐Dimensional Extended Structures Containing Te5n‐ Units

Chemischer InformationsdienstVolume 17, Issue 9 Physical Inorganic Chemistry ChemInform Abstract: Hypervalent Tellurium in One-Dimensional Extended Structures Containing Te5n- Units J. BERNSTEIN, J. BERNSTEINSearch for more papers by this authorR. HOFFMANN, R. HOFFMANNSearch for more papers by this author J. BERNSTEIN, J. BERNSTEINSearch for more papers by this authorR. HOFFMANN, R. HOFFMANNSearch for more papers by this author First published: March 4, 1986 https://doi.org/10.1002/chin.198609002AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume17, Issue9March 4, 1986 RelatedInformation

Hypervalent tellurium in one-dimensional extended structures containing Te5n- units

Hypervalent tellurium in one-dimensional extended structures containing Te5n- units