Siloxide

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Siloxides are chemical compounds with the formula R3SiOM, where R is usually an organic group and M is usually a metal cation. Also called silanoates, they are derived by deprotonation of silanols. They also arise by the degradation of siloxanes by base: [1]

R3SiOSiR3 + 2 NaOH → 2 R3SiONa + H2O

Cleavage of cyclic siloxanes affords siloxides:

(Me2SiO)3 + MeLi → Me3SiOSiMe2OSiMe2OLi

These anions function as ligands for metal ions, forming complexes similar to metal alkoxides. Sodium trimethylsiloxide is useful for generating metal complexes by salt metathesis reactions. A very bulky siloxide is tert-butyl 3SiO, sometimes called silox.

Siloxides are weaker net donors than alkoxides because pπ-d donation has to compete with backbonding from the oxygen atom into the low-lying Si-C σ* orbitals. [1]

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Metal–ligand multiple bond

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Silsesquioxane

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Silylation is the introduction of a (usually) substituted silyl group (R3Si) to a molecule. The process is the basis of organosilicon chemistry.

Disiloxane Chemical compound

Disiloxane has the chemical formula Si
2
H
6
O
. It is the simplest known siloxane with hydrogen only R groups. The molecule contains six equivalent Si-H bonds and two equivalent Si-O bonds. Disiloxane exists as a colorless, pungent gas under standard conditions. However, it is generally safe for human use as evidence in its widespread use in cosmetics. It is also commonly known as disilyl ether, disilyl oxide, and perhydrodisiloxane

Phosphinimide ligands

Phosphinimide ligands, also known as phosphorane iminato ligands, are any of a class of organic compounds of the general formula NPR3. The R groups represent organic substituents or, in rare cases, halides or NR2 groups. NPR3 is isoelectronic with phosphine oxides (OPR3) and siloxides ([OSiR3]), but far more basic. By varying the R groups on P, a variety of ligands with different electronic and steric properties can be produced, and due to the high oxidation state of phosphorus, these ligands have good thermal stability. Many transition metal phosphinimide complexes have been well-developed as have main group phosphinimide complexes.

Tantalum(V) ethoxide Chemical compound

Tantalum(V) ethoxide is a metalorganic compound with formula Ta2(OC2H5)10, often abbreviated as Ta2(OEt)10. It is a colorless solid that dissolves in some organic solvents but hydrolyzes readily. It is used to prepare films of tantalum(V) oxide.

Sodium trimethylsiloxide Chemical compound

Sodium trimethylsiloxide is an organosilicon compound with the formula NaOSi(CH3)3. It is the sodium salt of the conjugate base derived from trimethylsilanol. A white solid, its molecular structure consists of a cluster with Na-O-Na linkages on the basis of closely related compounds.

References

  1. 1 2 Krempner, Clemens (2011). "Role of Siloxides in Transition Metal Chemistry and Homogeneous Catalysis". Eur. J. Inorg. Chem. 2011 (11): 1689. doi:10.1002/ejic.201100044.