Detailed Update of Ditechnetium and Dirhenium Chemistry

Dirhenium Compounds. In the case of dirhenium chemistry, the most striking advances have been encountered in the case of the so-called electron-rich Re-Re triple bonds (c2jt4526 2 electronic configuration) where a variety of new reactivity patterns have been established. Studies on such species constitute one of the most rapidly developing areas of multiple bond chemistry. 

An interesting facet of the photochemistry of [Re2Cl8]2- involves the electron-transfer chemistry of the luminescent excited state [Re2Clg]2-, which is an 88 singlet30,31.  

A variety of dirhenium(III) carboxylates of the types Re2(02CCH3)4Br2, trans-Re2(02CCH3)2X4 (X = Cl or Br), cis-Re OjCCH Lj (L = py, DMSO, etc.), Re2(02CH)2Cl4L2 (L = DMF or DMSO), and (NH4)2[Re2(02CH)2Cl6] have been 

Chemical reactions are as follows (a) reaction with PR3 at room temperature (b) reaction with PR3 under reflux (c) reaction with NO+PFj in CH2CI2 at room temperature (d) reaction with NO+PF in CH3CN at room temperature (e) reaction with Cp2Co in acetone at room temperature (f) reaction with one-equivalent of Cl- (g) reaction with one equivalent of PR3. 

Another product from the same reaction that affords Re2Cl3(Ph2Ppy)2-[(QHj)(C6H4)Ppy] is the dirhenium(II) salt [Re2Cl2(Ph2Ppy)4]Cl2. It can be metathesized 

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