{{Chembox | ImageFile = NaSilox2.png | ImageSize = 220 | ImageName = Stereo structural formula of tetrameric sodium silox | IUPACName = Sodium silox | SystematicName = Sodium tri-''tert''-butylsilanolate |Section1={{Chembox Identifiers | CASNo = 461703-02-6 | CASNo_Ref = {{cascite|correct|chemspider}} | ChemSpiderID = 35766904 | PubChem = 23701721 | SMILES = [Na+].CC(C)(C)[Si]([O-])(C(C)(C)C)C(C)(C)C | StdInChI = 1S/C12H27OSi.Na/c1-10(2,3)14(13,11(4,5)6)12(7,8)9;/h1-9H3;/q-1;+1 | StdInChIKey = QAGFKHQOLBYGIF-UHFFFAOYSA-N}} |Section2={{Chembox Properties | C=12 | H=27 | Na=1 | O=1 | Si=1 | Appearance = colourless solid}} |Section3={{Chembox Hazards | ExternalSDS = | FlashPt= | AutoignitionPt = | HPhrases = | PPhrases = | GHS_ref = }} }} '''Sodium silox''' is the name for an organosilicon compound that serves as a source of the siloxide anion [(CH<sub>3</sub>)<sub>3</sub>C]<sub>3</sub>SiO<sup>−</sup>. Complexes of this bulky anionic ligand often adopt with low coordination numbers. Examples include Ti(silox)<sub>3</sub>, Nb(silox)<sub>3</sub>(PMe<sub>3</sub>), and [Cr(silox)<sub>3</sub>]<sup>−</sup>.
==Properties of silox and related complexes== The sodium derivative, which has salt-like properties, is a cubane-type cluster.<ref>Lerner, Hans-Wolfram; Scholz, Stefan; Bolte, Michael "The Sodium Siloxides (tBu<sub>3</sub>SiONa)<sub>4</sub> and (tBu<sub>2</sub>PhSiONa)<sub>4</sub>: Synthesis and X-ray Crystal Structure Analysis" Organometallics 2002, 21, 3827-3830. {{doi|10.1021/om020318v}}</ref>
Related bulky anionic ligands include C<sub>5</sub>Me<sub>5</sub><sup>−</sup>, (Me<sub>3</sub>Si)<sub>2</sub>N<sup>−</sup>, and NacNac<sup>−</sup>. Silox has a larger cone angle than C<sub>5</sub>Me<sub>5</sub><sup>−</sup> and is a poorer donor. It is also larger than silylamides. For these reasons, silox anion forms highly unsaturated complexes.
Complexes with high coordinative unsaturation display high reactivity so long as they do not undergo intramolecular reactions. Silox offers this possibility. Examples of high reactivity exhibited by metal-silox compounds include the C-O bond in carbon monoxide and the C-N bond in pyridine.<ref>Peter T. Wolczanski "Chemistry of electrophilic metal centres coordinated by silox (<sup>t</sup>Bu<sub>3</sub>SiO), tritox (<sup>t</sup>Bu<sub>3</sub>CO) and related bifunctional ligands" Polyhedron, 1995, 14, 3335-3362. {{doi|10.1016/0277-5387(95)85014-7}}.</ref>
==Preparation== Na(silox) is usually prepared by deprotonation of the silanol (t-Bu)<sub>3</sub>SiOH, which is prepared by a multistep route via the intermediacy of (t-Bu)<sub>2</sub>SiF<sub>2</sub>.<ref>Edward M. Dexheimer and Leornard Spialter, Lee D. Smithson "Tri-t-butylsilane: synthesis, physical properties, derivatives, and reactivity towards ozonolysis, chlorination, fluorination, and hydrolysis" Journal of Organometallic Chemistry 102, 1975, 21-27.{{doi|10.1016/S0022-328X(00)90256-0}}.</ref> It is also obtained by treatment of <sup>t</sup>Bu<sub>3</sub>SiNa with nitrous oxide.
==Related compounds== *Sodium trimethylsiloxide
==References== {{Reflist}}
Category:Organosilicon compounds Category:Sodium compounds