Abstract
When 4,4a-dihydro-3,3-dimethyl-1-phenyl-4,4-bis(trimethylsilyl)-3H-2-oxa-3-sila-naphthaline (silaoxine C22H34OSi3 (3); orthorhombic, space group Pna21, Z=4) was thermolized in a CO2 atmosphere, the corresponding oxasilacyclobutane (silaoxetane) 5 was quantitatively formed. The [2+2] cycloreversion of the silaoxetane 5 occurred at temperatures higher than 120°C to give exclusively Ph2C=C(SiMe3)2 and (Me2SiO)
n
. Single crystals of Ph2C=C(SiMe3)2 (6; monoclinic, space group C2/c, Z=8) were isolated from this reaction. When the azasilacyclobutane (silaazetidine) C25H43NSi4 (4; monoclinic, space group P21/n, Z=4) was reacted with an excess of CO2 at 100°C an unknown intermediate was formed along with the benzophenonimine Ph2C=N(SiMe3). The NMR resonances of this intermediate indicates the formation of the β-silalactone (silaoxetanone) C10H24O2Si3 (7). At temperatures higher than 120°C the silaoxetanone 7 decomposed to give (Me3Si)2C=C=O and (Me2SiO)
n
, respectively.
摘要:当4,4a-二氢-3,3-二甲基-1-苯基-4,4-双(三甲基硅基)-3H-2-氧-3-硅-萘(硅氧烷C22H34OSi3(3);正交晶系,空间群Pna21,Z=4)在CO2气氛下热解时,定量形成了相应的氧硅环丁烷(硅氧环氧烷)5。硅氧环氧烷5的[2+2]环反应发生在高于120℃的温度下,仅给出Ph2C=C(SiMe3)2和(Me2SiO)n。从该反应中分离出了Ph2C=C(SiMe3)2(6;单斜晶系,空间群C2/c,Z=8)的单晶。当氮硅环丁烷(硅氮环氧烷)C25H43NSi4(4;单斜晶系,空间群P21/n,Z=4)与过量的CO2在100℃反应时,除苯基酮亚胺Ph2C=N(SiMe3)外,还形成了一个未知的中间体。该中间体的NMR共振指示了β-硅内酯(硅氧环氧酮)C10H24O2Si3(7)的形成。在高于120℃的温度下,硅氧环氧酮7分解为(Me3Si)2C=C=O和(Me2SiO)n。