Cyclopentadienyl complex triple-decker sandwich

The only complex containing a complete cyclopentadienyl ring sandwiched between 2 metal atoms that has been the subject of an X-ray crystallographic study is the triple-decker sandwich compound... 

Scheme 6.11 Triple-decker sandwich complexes 31-35 with bridging P5 and Pg ring ligands (the substituents at the cyclopentadienyl rings are alkyl groups)...

E. Dubler, M. Textor, H. R. Oswald, and A. Salzer, X-Ray Structure Analysis of the Triple-Decker Sandwich Complex Tris(j -cyclopentadienyl)dinickel Tetrafluoroborate,... 

Cationic cyclopentadienyl iron fragments have been generated by photolysis of [(C5H5)Fe(C6H6)] [PF6] and shown to form transient cationic triple-decker sandwich complexes with [(t-Bu3C3P2)Fe(r-Bu2P3)]. Similar photolytic removal of cyclopentadienyliron moieties has been utilized as a key step in the synthesis of ether and thioether building blocks for polymer synthesis. ... 

Four possible general structural types are illustrated in Fig. 3. Structure types A and B are represented by the mono- and bis(tricarbonyl-chromium) complexes (ML = Cr(CO)3) and double decker and triple decker sandwich complexes (e.g. MLx = FeCp RufCgHg) CoCp ). The benzene rings of the cyclophane ligands can be replaced by cyclopentadienyl- or cyclobutadienyl-ligands. 

Most closely analogous to cyclopentadienyls are borollides, the dianions of boroles. Borol-lide complexes are often prepared by a procedure like that in Scheme 3.3, beginning with the dehydrogenation of a borolene. This reaction with a rhodium(I) species formed a "triple-decker sandwich." - ... 

Dubler E, Textor M, Oswald H-R, Salzer A (1974) X-ray structure-analysis of triple-decker sandwich complex tris (ti-cyclopentadienyl)dinickel tetrafluoroborate. Angew Chem 86 135-... 

This section describes the organovanadium compounds containing jj -cyclopentadienyl (Cp) or substituted (Cp ) ligands, which are classified into half-sandwich (see Halfsandwich Complexes), sandwich (see Sandwich Compound), bent sandwich (see Bent Metallocenes), and pseudo-triple decker derivatives. Cyclopentadienyl vanadium compounds are nsed for the synthesis of varions vanadium compounds as mentioned above. Generally, the oxidation state of the cyclopentadienyl vanadium complexes is Irom — 1 to -1-5. 

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