Homoleptic complexes rhenium

A homoleptic thioether complex can be prepared by the reaction of perrhenate with 9S3 (15b) in glacial add in the presence of SnCl2. Red-brown crystals of [Re(9S3)2][PF6]2 have been isolated and studied structurally showing a mean Re—S distance of 2.37 A. Treatment of [Re(9S3)2] PF6]2 (268) with ascorbic acid does not result in reduction of the rhenium atom but in its oxidation and the release of ethene by decomposition of the cyclic thioether. The resulting rhenium(III) complex [Re(9S3)(SCH2CH2SCH2CH2S)][PF6] has been isolated and studied by X-ray crystallography. ... 

Re(9S3)2](PF6)2-2CH3N02 First homoleptic rhenium(n) complex used in 186Re radiotherapy 1995CC161... 

By way of example, we can focus on the cyano complexes. Palladium and platinum can form homoleptic complexes with two, four, or six cyanides, depending on the metal oxidation state zero, two, and four, respectively. Rhenium forms heptacyano complexes in its - -3 and -t-4 oxidation states but forms an octacyano complex in its -t-5 state. Molybdenum and tungsten also appear commonly in octacyano complexes for +4 and - -5 oxidation states, and heptacyano analogs for the - -2 and - -3 cases, with only one occurrence of [Mo(CN)6]" anions in two oxidation states (n = 3, 4). Similar situations can be found with phosphine or carbonyl complexes. For instance, the group... 

Photochemical reactions of the homoleptic carbonyls of manganese and rhenium with donor ligands have been thoroughly studied in recent years (2-4). The nature of the primary photoproducts of the complexes M2(CO)10 (M = Mn, Re) has been investigated by different techniques (151-165). The... 

Homoleptic manganese(II) compounds are very unstable, pyrophoric, and very sensitive to water. Homoleptic rhenium complexes also readily react with oxygen, water, and alcohols. The compound Li2[Re2Meg] is also pyrophoric. Heteroleptic compounds, like compounds of elements of other groups, are less reactive. 

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