Synthesis of Ladder and Cage Silsesquioxanes from 1,2,3,4-Tetrahydroxycyclotetrasiloxane
作者:Masafumi Unno、Akiko Suto、Keisuke Takada、Hideyuki Matsumoto
DOI:10.1246/bcsj.73.215
日期:2000.1
The versatility of cis,cis,cis-1,3,5,7-tetrahydroxy-1,3,5,7-tetraisopropylcyclotetrasiloxane (1) as a precursor of cage and ladder siloxanes is presented. Compound 1 reacted with 1,3-dichloro-1,1,3,3-tetraisopropyldisiloxane in pyridine to give 1,3,5,5,7,7,9,11,13,13,15,15-cis-cisoid-cis-dodecaisopropyltricyclo[9.5.1.13,9]octasiloxane (2) in 20% yield. The reaction proceeded with retention of the configuration of the silicon atoms, and only syn-type isomer was obtained. The reaction of 1 with 1,1,3,3-tetrachloro-1,3-diisopropyldisiloxane in pyridine produced hexakis(isopropylsilsesquioxane) (T6) (3) in 25% yield. Treatment of 1 with dicyclohexylcarbodiimide (DCC) as dehydrating reagent led to the formation of octakis(isopropylsilsesquioxane) (T8) (4) in 45% yield. The crystal structures of 2, 3, and 4 are reported.
介绍了顺式、顺式、顺式-1,3,5,7-四羟基-1,3,5,7-四异丙基环四硅氧烷(1)作为笼状和阶梯状硅氧烷前体的多功能性。化合物 1 与 1,3-二氯-1,1,3,3-四异丙基二硅氧烷在吡啶中反应,得到 1,3,5,5,7,7,9,11,13,13,15,15-顺式-顺式-十二异丙基三环[9.5.1.13,9]八硅氧烷(2),收率为 20%。反应过程中保留了硅原子的构型,只得到了同分异构体。1 与 1,1,3,3-四氯-1,3-二异丙基二硅氧烷在吡啶中反应生成六(异丙基硅倍半氧烷)(T6)(3),收率为 25%。用二环己基碳二亚胺(DCC)作为脱水试剂处理 1,可生成八(异丙基硅倍半氧烷) (T8) (4),产率为 45%。报告了 2、3 和 4 的晶体结构。