Ditelluride complex

Steigerwald has described the preparation of [Fe2(CO)2(PEt3)2(C5H5)2-(ji-Ten)] (174, n = 1 175, n = 2) (163), which are useful precursors for FeTe and FeTe2, from reactions between [Fe2(CO)4(C5H5)2] and one or two equivalents of Et3PTe. Similarities exist between 174 and 154 and between 175 and 172, with 175 being a further example of a dimetalla-ditelluride complex. 

The ditelluride complex is a centrosymmetric dimer [177] and the Yb is tetrahedrally bonded to two Cp ligands and to the Te - ion. The structure of Se complex [178] has a linear Se-Yb-Se bridge (170.1°) with two Cp Yb units mutually staggered and the compound is seven coordinate. The structure of Ce complex [180] shows a rare example of Ce-S dative bond with Ce-S distances of 3.058 and 3.072 A. 

The complexes UCljPh2X2 (X = Se or Te) are precipitated when a solution of the diselenide or ditelluride in benzene is added to a solution of the trichloroacryloyl chloride complex, UCls-GjCUO, in the same solvent. 

It is also relevant to record that several iron-carbonyl complexes with bridging, and in one case terminal, aryltellurol ligands have been prepared by reaction of Fe(CO)5, Fe(CO)12 or [ji-CpFe(CO)2]2 with diaryl ditellurides and which, together with complexes containing other transition metal carbonyls, e.g, ruthenium, osmium and manganese, provide a substantial number of interesting compounds.2... 

Tellurolysis of [(Me3Si)2N]2M with (Me3Si)3SiTeH in the presence of base gives the 4-coordinate ditellurides, while the structures of the dmpe complexes of Mn(II) and Fe(II) show Si—Te bond lengths of 250 -252 pm, shorter than those in Fe(II) complexes (with values 253.7 -254.6 pm), while that in the Co(I) derivative was shorter than both at 249.4 pm. 

Ditantalacyclobutadiene, preparation, 5, 155 Ditellurides, addition to alkynes, 10, 754 Dithiagermastannacyclobutane, preparation, 3, 741—742 Dithiocarbamate carbonyl complexes... 

Although upon complex formation, ditellurides generally undergo cleavage of the Te-Te bond with formation of... 

Other Elements - Irradiation ((>300 nm) of the allene (366) in the presence of diphenyl diselenide affords a high yield of the adduct (367) as an El Z mixture (28 72). Diphenyl disulfide affords a complex mixture of products with the same allene while diphenyl ditelluride does not react. The difference between the sulfide and the selenide is due to the lower ability of diphenyl disulfide to react with carbon radicals. When a mixed system is used [(PhS)2 (PhSe)2 as a 1 1 mixture] mixed addition occurs. Thus with the allene (366) an almost quantitative yield of (368) is produced and other allenes (369) are also reactive imder these conditions, affording (370). The use of diphenyl selenide as a catalyst for the photochemical isomerism of some carotenoids has been described. ... 

The electronic spectrum of (14) and its isomer (20) which both form highly conductive complexes with TCNQ and analogous acceptors have been reported <90BCJ244l>. The solvatochromic behavior of the ditellurides (1), (21), and (22) has also been discussed <93JA885>. 

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