Method for preparing silica filled organosiloxane compositions
申请人:Dow Corning Toray Silicone Co., Ltd
公开号:US05364896A1
公开(公告)日:1994-11-15
The triorganosiloxydiphenylsilanols of the present invention are novel silicone compounds that are useful as plasticizers for silicone rubbers. The present invention also relates to a method for preparing these compounds in high yield and purity and a method for preparing filled curable organosiloxane compositions using the present compounds as plasticizers.
Reactions of trimethylsiloxychlorosilanes with lithium metal – On the mechanism of the formation of trimethylsiloxysilyllithium compounds LiSiRR’(OSiMe3)
作者:Joerg Harloff、Eckhard Popowski
DOI:10.1016/j.jorganchem.2008.01.023
日期:2008.4
The reaction pathway for the formation of the trimethylsiloxysilyllithium compounds (Me3SiO)RR′SiLi (2a: R = Et, 2b: R = iPr, 2c: R = 2,4,6-Me3C6H2 (Mes); 2a–c: R′ = Ph; 2d: R = R′ = Mes) starting from the conversion of the corresponding trimethylsiloxychlorosilanes (Me3SiO)RR′SiCl (1a–d) in the presence of excess lithium in a mixture of THF/diethyl ether/n-pentane at −110 °C was investigated.
形成三甲基甲硅烷氧基硅烷基锂化合物(Me 3 SiO)RR'SiLi(2a:R = Et,2b:R = i Pr,2c:R = 2,4,6-Me 3 C 6 H 2(Mes );2a – c:R'= Ph;2d:R = R'= Mes),是在混合物中存在过量锂的情况下,由相应的三甲基甲硅烷氧基氯硅烷(Me 3 SiO)RR'SiCl(1a – d)转化而来在-110°C下研究了THF /二乙醚/正戊烷的合成。
Reaktionen von Trimethylsiloxychlorsilanen (Me3SiO)Me2−nPhnSiCl (n=0,1,2) mit Lithium—Bildung von Trimethylsiloxy-substituierten Silyl- und Disilanyllithiumver- bindungen sowie Di- und Trisilanen
作者:Jörg Harloff、Eckhard Popowski、Hans Fuhrmann
DOI:10.1016/s0022-328x(99)00501-x
日期:1999.12
The trimethylsiloxychlorosilanes (Me3SiO)Me2-nPhnSiCl (1: n = 0; 2: n = 1; 3: n = 2) were allowed to react with lithium metal in tetrahydrofuran (THF) and in a mixture of THF-diethylether-n-pentane in volume ratio 4:1:1 (Trapp mixture). The reaction of 1 with lithium metal in TNF under refluxing leads to the home-coupling product [(Me3SiO)Me2Si](2) (4). A mixture of 1 and Me3SiCl in molar ratio 1:2 reacts with lithium metal in THF to give 4 and the cross-coupling product (Me3SiO)Me2SiSiMe3 (7). The silyllithium derivatives Me3SiO(SiMePh)(n)Li (8: n= 1; 9: n = 2; 10: n = 3) and Me3SiSiMePhLi (11) are formed in the reaction of 2 with lithium metal in THF at - 78 degrees C and in the Trapp mixture at - 110 degrees C. Main product in both cases is 9. 8-11 are trapped by Me3SiCl and HMe2SiCl. The trapping products (Me2SiO)SiMePhSiMe3 (13a), Me3SiO(SiMePh)(2)SiMe2R (14a, 14b; a: R = Me, b: R = H), Me3SiO(SiMePh)(3)SiMe2R (15a, 15b) and Me3SiSiMePhSiMe2R (16a, 16b) are obtained. The reaction of 3 with lithium metal like 2 produces the silyllithium derivatives Me3SiO(SiPh2)(n)Li (18: n = 1, 19: n = 2) and Me3SiSiPh2Li (20), wich are frapped by Me3SiCl and HMe2SiCl to give the corresponding disilanes (Me3SiO)SiPh2SiMe2R (23a, 23b) and trisilanes Me3SiO(SiPh)(2)SiMe2R (24a, 24b) as well as Me3SiSiPh2SiMe2R (25a, 25b). In addition to 18, 19 and 20 LiSiPh2SiPh2Li (21) is formed in a small amount in the reaction of 3 with lithium metal at - 78 degrees C to afford tetrasilanes [RMe2SiPh2Si](2) (26a, 26b) after trapping by Me3SiCl and HMe2SiCl. The disilane (Me3SiO)SiMeR'SiMe3 (17) (R' = 3,4,5,6-tetrakis(trimethylsilyl)cyclohex-1-enyl) is produced by reaction of a mixture of 2 and Me3SiCl in molar ratio 1:6 with 6 equivalents of lithium at - 78 degrees C in THF. The reaction of a mixture of 3 and Me3SiCl in the molar ratio 1:10 with 11 equivalents of lithium under the same conditions gives (Me3SiO)SiR'2SiMe3 (27).