Acetolysis of 4,4-disubstituted 4-silacyclohexyl tosylates: effect of remote silicon substitution on organic reactivity
作者:Stephen S. Washburne、Ram R. Chawla
DOI:10.1016/s0022-328x(00)98112-9
日期:1977.6
and phenyl-methyl-substituted 4-silacyclohexyl tosylates (IcId) were compared with isosteric 4,4-disubstituted cyclohexyl tosylates. The rates of acetolysis of the silatosylates were three to five times greater than those of the carbocyclic analogs. With the exception of Ia, which largely fragmented to di-4-pentenyltetramethyldisiloxane, the acetolysis products of compounds I were acetates and olefins
比较了4,4-二甲基-(Ia),4,4-二苯基-(Ib)和苯基-甲基取代的4-硅烷基环己基甲苯磺酸酯(IcId)与等排性4,4-二取代环己基甲苯磺酸酯。硅藻土酸酯的乙酰分解速率是碳环类似物的三到五倍。除了Ia,其大部分片段化为二-4-戊烯基四甲基二硅氧烷外,化合物I的乙酰分解产物是乙酸酯和烯烃,其比例与环己基甲苯磺酸酯的比例相似。结论是,γ-甲硅烷基取代基对甲苯磺酸酯的动力学和产物确定作用很小,尽管在通过重排可以形成稳定的β-甲硅烷基碳离子的情况下,如Ia,碎裂产物将占主导地位。