Synthesis and reactivity of silicon transition metal complexes. 38. Metallo-silanols and siloxanes. 12. C5R5(OC)2(Me3P)M-Substituted silanetriols of molybdenum and tungsten (R = H, Me). Synthesis via oxofunctionalization of metallotrihydridosilanes and transformation into the multifunctionalized metallotetrasiloxane C5Me5(OC)2(Me3P)WSi(OSiMe2H)3

Abstract

Hydrolysis of organotrichlorosilanes RS1CI3 leads to organosilanetriols RSi(OH)3, which usually undergo rapid condensation to siloxanes.2 When bulky ligands are attached to the silicon, it is possible to isolate and characterize organosilanetriols.3 Recently, the first silanetriols attached to transition metals L"M-Si(OH)3 [L"M = (OC)(Cl)(Ph3P)2Os4 and Cp(OC)2-Fe5] have been obtained from hydrolysis of the corresponding trichlorosilyl complexes, indicating that metal fragments can stabilize silanetriols. The stabilization is derived not only from steric effects of the metal group but also from its electron donation to the silicon. The hydrolysis route is limited by the fact that electron-rich metal fragments reduce substitution rates at silicon, a situation observed for the metallotrichlorosilanes C5R5(OC)2(Me3P)M-

Recent Developments in the Synthesis and Structure of Organosilanols

“…N-Bonded silanediols can also be prepared by derivatizing the corresponding silanetriols. Thus, one of the hydroxyl groups of the silanetriol can be engaged in reaction of ArN(SiMe 3 )Si(OH) 3 [Ar ) 2,4,6-Me 3 -C 6 H 2 (178), 2,6,Me 2 -C 6 H 3 (179), 2,6-i-Pr 2 -C 6 H 3 (65)] with trimethylsilyl chloride to afford the corresponding silanediols ArN(SiMe 3 )Si(OH) 2 (OSiMe 3 ) [Ar ) 2,4,6-Me 3 -C 6 H 2 (180), 2,6,Me 2 -C 6 H 3 (181), 2,6-i-Pr 2 -C 6 H 3 (182)] (eq 2, Scheme 45). 158 An unusual rearrangement reaction of the silanetriol 2,4,6-Me 3 -C 6 H 2 -N(SiMe 3 )Si(OH) 3 (178) affords the silanediol 183 (Scheme 46).…”

Ruthenium Silyl Complexes Containing the Cp(PMe3)2Ru Moiety: Preparation, Substituent Effects, and Silylene Character in the Ru−Si Bond

“…Malisch and co-workers successfully prepared a wide variety of late transition metal silyl complexes of the type L n MSiX 3 (ML n = CpCr(CO) 3 , CpMo(CO) 3 , Cp*Mo(CO) 3 , CpMo(CO) 2 (PMe 3 ), Cp*Mo(CO) 2 (PMe 3 ), CpW(CO) 3 , Cp*W(CO) 3 , CpW(CO) 2 (PMe 3 ), Cp*W(CO) 2 (PMe 3 ), CpFe(CO) 2 , Cp*Fe(CO) 2 , CpRu(CO) 2 , Cp*Ru(CO) 2 ; SiX 3 = SiHCl 2 , SiHMeCl, SiHMe 2 , SiPhHCl, SiPh 2 H, etc.) by reacting metal anions with the corresponding chlorosilane in hydrocarbon solvent. − Controlled exchange reactions at silicon afforded a variety of metallohydrosilanes, − -fluorosilanes, -aminosilanes, , -silanols, ,− and -alkoxysilanes…”

Solid-state structure and condensation reaction of (triphenylmethyl)silanetriol

“…Especially silanetriols, which are unstable compounds, can be useful precursors for the synthesis of silsesquioxanes, ladder polymers, and metallosilsesquioxanes [2a,3-5]. Since stable c-hexylsilanetriol was first isolated and characterized by single crystal X-ray structure analysis in 1982 [6], some stable silanetriols bearing a bulky substituent have been isolated and studied for their structures and properties [7][8][9][10][11][12][13][14][15][16][17][18]. A bulky substituent on the silicon of silanetriol makes OH groups on the silicon stabilized for self-condensation reaction.…”