26799-07-5

Upstream product

• 4142-85-2 1,1,1,3,3,3-hexachloro-1,3-disilapropane 
• 558-13-4 carbon tetrabromide 
• 4206-75-1 phenylchlorosilane 
• 694-53-1 phenylsilane 
• 1631-90-9 bromo-phenyl-silane 
• 74-95-3 1,1-dibromomethane 
• 124462-66-4 tetrakis(phenylsilyl)methane 

Downstream Products

• 26799-08-6 Si,Si,Si',Si'-tetrachloro-Si,Si'-diphenyl-Si,Si'-methanediyl-bis-silane 
• 26883-94-3 1,3,5,7,9,11-hexaphenyl-2,4,6,8,10,12-hexaoxa-1,3,5,7,9,11-hexasila-tetracyclo[5.5.1.1^3,11.1^5,9]pentadecane 

Relevant academic research and scientific papers

Synthetic Pathways to Disilylmethane, H3SiCH2SiH3 and Methyldisilane, CH3SiH2SiH3

Disilylmethane is available in a four-step synthesis starting with phenylsilane.This is converted into chlorophenylsilane by HCl/AlCl3.The reaction of PhSiH2Cl and bibromomethane with magnesium in tetrahydrofuran affords bis(phenylsilyl)methane, which yields bis(bromosilyl)methane by treatment with anhydrous hydrogen bromide. (BrH2Si)2CH2 is converted into disilylmethane by reduction with LiAlH4 in a two-phase system using a phase-transfer catalyst. - Methyldisilane is available by alkylation of monohalodisilane, XSi2H5 (X=Cr, Br), with methyllithium in a high-boiling ether or by silylation of bromomethylsilane with silylpotassium.Due to secondary silylation reactions the overall yields of methyldisilane are low in all cases.

A Synthetic Route to Poly(silyl)methanes via Poly(phenylsilyl)methanes and Poly(bromosilyl)methanes

A three-step synthesis is presented for di- and tri(silyl)methane, two feedstock gases for the chemical vapour deposition of amorphous hydrogenated silicon/carbon alloys (a-SiC:H).Chloro(phenyl)silane and di-or trihalomethanes react with magnesium in tetrahydrofuran to give high yields of bis- and tris(phenylsilyl)methane, respectively.The two products can be converted into bis- and tris(bromosilyl)methane by treatment with anhydrous hydrogen bromide.Bromide/hydride substitution in these precursors is accomplished with lithium aluminum hydride in a two phase system using a phase-transfer catalyst.The compounds CH2(SiH2Ph)2, CH(SiH2Ph)3, CH2(SiH2Br)2, CH(SiH2Br)3, CH2(SiH3)2, and CH(SiH3)3 have been characterized by standard spectroscopic methods, and the crystal and molecular structure of CH(SiH2Ph)3 has been determined by single-crystal X-ray diffraction.The molecule adopts a conformation with crystallographic C3 symmetry.This result is discussed with regard to the structure of related molecules with three substituents of potential Cs symmetry at a tetrahedral center. - Key Words: CVD feedstock gases / Poly(bromosilyl)methanes / Poly(phenylsilyl)methanes / Poly(silyl)methanes / Silanes