1,3-Migration of triorganosilyl groups from carbon to oxygen in highly crowded organosilanols
作者:Abdulrahman I. Al-Mansour、Mohammed A.M.R. Al-Gurashi、Colin Eaborn、Faraedon A. Fattah、Paul D. Lickiss
DOI:10.1016/0022-328x(90)87196-k
日期:1990.8
at room temperature in 0.10 M NaOMe/MeOH. The reactions involve 1,3-migration from carbon to oxygen within a silanolate ion to give a carbanion, which rapidly acquires a proton from the solvent. The migration is facilitated by relief of steric strain and stabilization of the forming carbanionic centre by the three attached silyl groups. The relative reactivities of the various silanols may be determined
硅烷醇(Me 3 Si)CSiMe 2 OH已显示异构化为0.5的(Me 3 Si)2 CH(SiMe 2 OSiMe 3)(其进一步反应生成(Me 3 Si)2 CH(SiMe 2 OMe))M NaOMe / MeOH,异构化为约。在回流下6小时后90%完成。(PhMe 2 Si)3 CSiMe 2 OH(得到(PhMe 2 Si)2 CH(SiMe 2 OSiMe 2 Ph)),(Me 3 Si)2 C(SiMePh 2SiMe 2 OH(得到(Me 3 Si)2 CH(SiMe 2 OSiMePh 2))和(Me 3 Si)3 CSiPh 2 OH(得到(Me 3 Si)2 CH(SiPh 2 OSiMe 3))采取放置要容易得多,并且在大约10分钟内完成。室温在0.10 M下2分钟NaOMe / MeOH。反应涉及硅烷醇离子中碳从1,3迁移到氧以生成碳负离子,碳负离子可快速从溶剂