Treatment of cyclotrisilane 1 with pyridinium bromide yields siliconium bromide 8a. In contrast, 1 reacts with six equivalents of AlMe3 as Lewis acid via an initial complex 13 to silane 10. Reaction of 1 with only three equivalents of AlMe3 forms 12, which is also obtained upon treatment of 10 with quinuclidine or 1. No analogous insertion reaction occurs with BH3, in which case the stable complexed
The Lewis acid B(C6F5)3 and the cyclic silane (ArN2Si)3 (1) (ArN=o‐(CH3)2NCH2C6H4) are useful precursors to access the silylene(II)–borane adduct ArN2Si‐B(C6F5)3 (2). Treatment of 2 with water led to coordination and gave the Lewispair (ArN2H2O)Si‐B(C6F5)3 (3) that exhibits a hydrogen‐bond‐stabilized silanol unit. It can be converted into the siloxane [(HArN)2SiOB(C6F5)3]2O (6) by dehydrogenation in
路易斯酸B(C 6 F 5)3和环状硅烷(Ar N 2 Si)3(1)(Ar N = o-(CH 3)2 NCH 2 C 6 H 4)是接触亚甲硅烷基的有用前体(II)-硼烷加合物Ar N 2 Si-B(C 6 F 5)3(2)。用水处理2导致配位并产生Lewis对(Ar N 2 H 2 O)Si-B(C6 F 5)3(3)具有氢键稳定的硅烷醇单元。通过在碱的存在下进行脱氢,可以将其转化为硅氧烷[(HAr N)2 SiOB(C 6 F 5)3 ] 2 O(6)。表征化合物的异核NMR光谱数据得到了量子化学计算的支持。
Synthesis of di- and trisilanes with potentially chelating substituents
Silylenes 2 or 4, generated by thermolysis of cyclotrisilanes 1 and 3, were inserted into the SiCl or SiH bonds of monosilanes to yield a variety of disilanes, which can be further functionalized subsequently. In a few cases, trisilanes are accessible by the reaction of 1 with disilanes. The reaction of a metalated silane with a chlorosilane is an alternative method for the formation of SiSi bonds
Reactions of a cyclotrisilane with styrene derivatives and diarylacetylenes—evidence for nucleophilic silylenes
作者:Johannes Belzner、Uwe Dehnert、Heiko Ihmels
DOI:10.1016/s0040-4020(00)01020-6
日期:2001.1
Silaindanes were obtained by reaction of hexakis[2-(dimethylaminomethyl)phenyl]cyclotrisilane (3) with 3 equiv. of various styrenes. Analogous treatment of 3 with p-methoxystryrene yielded a mixture of the corresponding silaindane and a 2:1 adduct between bis[2-(dimethylaminomethyl)phenyl]silylene (4) and the styrene. Competition experiments show that the addition rate of 4 to the triple bond of diarylacetylenes
通过六[2-(二甲基氨基甲基)苯基]环三硅烷(3)与3当量的反应获得硅丙二烷。各种苯乙烯。用对-甲氧基苯乙烯类似地处理3,得到相应的硅氢化茚和双[2-(二甲基氨基甲基)苯基]亚甲硅烷基(4)与苯乙烯之间的2∶1加合物的混合物。竞争实验表明,吸电子取代基可加快4向二芳基乙炔三键的加成速率。反应常数(ρ= + 0.85±0.21)表明4在这些反应中充当亲核试剂。环三硅烷3的这些反应中的速率确定步骤是形成甲硅烷基4。在60℃下,该一级过程的速率常数确定为(6.3±0.4)×10 -4 s -1。
A novel route to stable silacyclopropenes - First synthesis of silacyclopropenes bearing vinylic hydrogen
作者:Johannes Belzner、Heiko Ihmels
DOI:10.1016/0040-4039(93)88099-5
日期:1993.10
Starting from easily accessible cyclotrisilane 1, stable silacyclopropenes 3a - e are obtained in high yield. Their NMR spectroscopic data indicate appreciable charge delocalization throughout the three membered ring system.