Piano-stool complex

BMIM]C1/A1C13 have been used for the synthesis of the piano stool complexes [Mn(CO)3(r -arene)] (Scheme 6.1-7) [12]. 

Scheme 6.1-7 The synthesis of [Mn(CO)3(ri -arene)]-F piano stool complexes in [BMIMJCI/AICIj.

Of course, commercially available transition metal complexes are stable at room temperature because they have achieved an 18-electron noble gas-like electronic configuration. Thus, molecules like iron pentacarbonyl [Fe(CO)s], ferrocene [Fe(C5H5)2], as well as piano-stool complexes such as C5H5Co(CO)2 are chemically quite inert. In order to study bimolecular reactions, it is necessary to first prepare unsaturated complexes. For studies using molecular beams, one approach is through photolysis of a stable volatile precursor in a supersonic nozzle. 

There are very few examples of MOFs that have organometallic complexes as metalloligands, or so-called organometalloligands . However, Sweigart and co-workers (139-144) studied a number of such compounds. Their organo-metalloligand of choice was the piano stool complex [(Tj -benzoquinone)Mn (CO)3] , or /i-QMTC (Fig. 33). The C=0 moieties of the quinones can associate to secondary metal centers to form supramolecular networks with a rich diversity of... 

An important contribution of photoelectron spectroscopy to inorganic chemistry has been the use of this technique to understand the bonding capabilities of different ligands to metal centers. If the bonding for a series of ligands is to be compared, the metal fragment to which those ligands are bound must be similar. The d piano-stool complexes... 

Nazarov, A.A., Hartinger, C.G., Dyson, P.J. Opening the lid on piano-stool complexes an account of ruthenium(II)-arene complexes with medicinal applications. J. Organomet. Chem. 751, 251-260 (2014)... 

Similarly, the LiAlH4 reduction of the piano-stool complex [FeCp (// -dppe)-(CO)][PFe] in THF was also reported to proceed by single-electron transfer, leading to the isostructural 19-electron species [FeCp ( / -dppe)(CO)] which rapidly decoordinates to the 17-electron radical [FeCp ( / -dppe)(CO)] [88]. Finally, H-atom transfer onto the Fe center of this 17-electron species occurs to give the hydride [FeCp ( 7 -dppe)(CO)(H)] (Scheme 5) [88, 89]. 

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