The organoscience chemistry studies compounds in which a direct link between carbon and scandium occurs. Since scandium is a metal, organ scandal chemistry is a part of organometallic chemistry. Organoscience chemistry is especially of academic importance, although a number of groups of compounds are also used outside, for example as catalyst in polymerizations. A common source of scandium is scandium chloride.
As for the other elements of Group 3 of the Periodic Table, such as yttrium (organo-sodium compounds), and the lanthanides, the main form in which scandium occurs is that with oxidation number + III with the electron configuration [Ar] 3d4s). The members of this group have a large ion beam, for Sc, 88 μm is measured at 67 μm for Al, and unoccupied s, β and d orbital. These properties result in a behavior of hard live acid, combined with the tendency to high coordination numbers (9 to 12). The carbon-metal bond is therefore largely ionic. ligands
The body of organoscandium compounds has at least one cyclopentadienyl ligand (Cp). The general structure of these compounds is CpScX2, Cp2ScX or Cp3Sc. The mononuclear compounds have little applications because they are highly susceptible to nucleophilic addition due to the defective steric shielding of the metal, both by specific nucleophiles and by solvent.
Cp2ScCl can be prepared based on cyclopentadienyl sodium: ScCl3 + 2NaCp → ScCp2Cl + 2 NaCl
The chloride ion can be replaced by a large number of other ligands, for example by an allyl group in a reaction with allyl magnesium bromide: ScCp2Cl + C3H5MgBr → ScCp2 (n-C3H5) + MgClBr
Connections of the type Cp2ScX form dimers, the X-ligand forming the bridge between the two scandium atoms. Dimerization is prevented if the solvent itself can coordinate with scandium, such as tetrahydrofuran or acetonitrile, or when the Cp ligand is replaced by a spatially larger ligand such as the Cp * group. The compound Cp2ScCl is stable as monomer.
The compound with three Cp layers can also be prepared based on cyclopentadienyl sodium: ScCl3 + 3 NaCp → ScCp3 + 3 NaCl
The compound formed is air and moisture sensitive and forms polymeric chains with a Cp unit as a link between the different units and two η-Cp ligands. By adding an excess of coordinating solvent, the polymers are again broken. Navigation
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