74864-45-2

Upstream product

• 117940-82-6 Cp*2Zr(SiHMes₂)Me 
• 2923-28-6 silver trifluoromethanesulfonate 
• 5806-59-7 mesityllithium 
• 80785-72-4 tetramesityldisilene 
• 50490-74-9 chloro-di-(2,4,6-trimethylphenyl)silane 

Downstream Products

• 84537-17-7 C₃₆H₄₄Cl₂Si₂^(1-) 
• 80785-72-4 1,1,2,2-Tetramesityldisilenyl-Radikalanion 
• 84537-17-7 1,2-dichloro-1,1,2,2-tetramesityldisilane 

Relevant academic research and scientific papers

Dimesitylsilyl derivatives of zirconium

The preparation and characterization of (THF)2LiSiHMes2 (1, Mes = mesitvl) are reported. Compound 1 reacts with Cp2Zr(Me)Cl (Cp = η5-C5H5) to afford thermally unstable Cp2Zr(SiHMes2)Me (2), characterized by NMR spectroscopy. Similarly, the reaction of 1 with Cp*2Zr(Me)Br (Cp* = η5-C5Me5) provides the mixed alkyl silyl Cp*2Zr(SiHMes2)Me (3), which is stable for prolonged periods at room temperature. Compound 3 reacts cleanly with 1 equiv of HCl to give the chloro derivative Cp*2Zr(SiHMes2)Cl (4) and methane. Whereas carbon monoxide inserts cleanly into the Zr-C bond of 2, preferential CO insertion into the Zr-Si bond of 3 is observed. These reactions give Cp2Zr(η2-COMe)SiHMes2 (5) and Cp*2Zr-(η2-COSiHMes2)Me (6), respectively. Compound 6 is not stable in solution and slowly isomerizes to the enolate hydride Cp*2Zr[OC(=CH2)SiHMes2]H (7). The mechanism of the latter conversion is discussed. Hydrogen is shown to cleave the Zr-Si bond of 3 faster than the Zr-C bond. Reaction of 3 with AgOSO2CF3 results in oxidative cleavage of the Zr-Si bond giving MeS2HSiSiHMes2, Mes2SiH(OSO2CF3), MeS2SiH(Me), and Cp*2Zr(Me)OSO2CF3 (9), which was independently prepared from Cp*2ZrMe2 and AgOSO2CF3. Reaction of Cp*2ZrCl2 with 2 equiv of 1 does not give a bis(silyl) complex but instead results in dehydrohalogenation to MeS2SiH2 and the metallacycle Cp*2ZrCH2CCHCMeCHCMeCSiHMes (10).

SILICIUM-VERBINDUNGEN MIT STARKEN INTRAMOLEKULAREN STERISCHEN WECHSELWIRKUNGEN X. NEUE WEGE ZU 1,3,2,4-DITHIADISILETANEN

2,2,4,4-Tetraorganyl-1,3,2,4-dithiadisiletanes containing bulky organyl groups are obtained by copyrolysis of the disilanes R3Si-SiR3 with sulfur or sulfur hexafluoride, or better by reaction of the disilanes R2HSi-SiHR2 (R=CH3, i-C3H7, cyclo-C6H11, t-C4H9) with sulfur.In the case of R=t-C4H9 a considerable amount of the t-butyl groups is isomerized to the less crowded isobutyl groups.Monomeric silathiones R2Si=S are not available by this route.The sulfur insertion reaction into 1,1-di-t-butyl-1-silacyclobutane yields 2,4-di-t-butyl-2,4-dipropyl-1,3,2,4-dithiadisiletane instead of the expected 1,1-di-t-butyl-1-sila-2-thiacyclopentane.The latter compound, however, results from the crown ether catalyzed cyclisation reaction of 3-bromopropyltrichlorosilane with Na2S followed by transalkylation with t-butyllithium.The iodosilanes R3SiI (R=i-C3H7, cyclo-C6H11) react with Na2S to give the corresponding hexaorganyldisilathianes in high yields.