Synthesis of spirocyclosiloxanes by flash vacuum pyrolysis of 2,7-dimethyl-2,3: 7,8-diepoxy-5-silaspiro[4.4]nonane and cyclosiloxanes
作者:Clifford D. Juengst、William P. Weber、Georges Manuel
DOI:10.1016/s0022-328x(00)99534-2
日期:1986.7
Flash vacuum pyrolysis (FVP) of 2,7-dimethyl-2,3 : 7,8-diepoxy-5-silaspiro[4.4]-nonane with cyclotetra- or cyclopenta-siloxanes (D4 or D5) leads to products which apparently result from transannular insertion of [OSiO] or an equivalent synthon inti SIO single bonds of D4 or D5: 2,4,6,8,10-pentasila-1,3,5,7,9,11-hexaoxaspiro[5.5]undecane (D2QD2) and 2,4,6,8,10,12-hexasila-1,3,5,7,9,11,13-heptaoxaspiro[5
2,7-二甲基-2,3:7,8-二乙氧基-5-silaspiro [4.4]-壬烷与环四或环戊硅氧烷(D 4或D 5)的快速真空热解(FVP )导致产生明显的产物D 4或D 5的[OSiO]或等效的synthon intiSIO单键的环状插入导致的结果:2,4,6,8,10-pentasila-1,3,5,7,9 ,11-六氧六环[5.5]十一烷(D 2 QD 2)和2,4,6,8,10,12-六硅-1,3,5,7,9,11,13-七氧六环[5.7]十三烷(D 3 QD 2) 分别。已经用取代的环四硅氧烷如七甲基环四硅氧烷,乙烯基庚甲基环四硅氧烷,苯基庚甲基环四硅氧烷和氯甲基庚甲基环四硅氧烷研究了该反应的范围。在所有情况下,均获得了取代的螺环硅氧烷产物(D 2 QDD x)。已经证明29 Si NMR对于这些螺环硅氧烷的结构分配特别有用。