Observation of Direct Sulfenium and Selenenium Group Transfer from Thiiranium and Seleniranium Ions to Alkenes
Observation of Direct Sulfenium and Selenenium Group Transfer from Thiiranium and Seleniranium Ions to Alkenes
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DOI：
10.1021/ja900187y
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发表时间：
2009-03-18
影响因子：
15
通讯作者：
Cullen, Matthew D.
中科院分区：
文献类型：
--
作者：
Denmark, Scott E.;Collins, William R.;Cullen, Matthew D.
硫和硒离子从相应的三元环物种（“-铀离子”）进行立体定向转移到不同设施的未活化烯烃上。用六氟锑酸银处理相应的氯化物或硒化物，然后通过过滤去除氯化银，可以生成六氟锑酸硫铵和六氟锑酸硒铵。这些物质的(1)H、（13）C和（77）Se核磁共振谱均可记录。用烯烃处理s -苯基硫代铵离子会导致硫基在0℃时的缓慢转移。然而，s -甲基硫代铵离子即使在室温下也不会转移硫基。另一方面，硒-苯基硒和硒-丁基硒在-70℃时都瞬间转移了硒部分，通过从两个方向测量这些转移的平衡位置，可以建立1-苯基硒离子的相对稳定性：顺式四亚甲基<反式-2,3-二丙基，类似于反式-2,3-二异丙基<顺式六亚乙烯。
Sulfenium and selenenium ions undergo a stereospecific transfer from the corresponding three-membered ring species ("-iranium ions") to unactivated alkenes with varying facility. The thiiranium and seleniranium hexafluoroantimonates could be generated by treatment of the corresponding chloro sulfides or selenides with silver hexafluoroantimonate, followed by removal of the silver chloride by filtration. Clean (1)H, (13)C, and (77)Se NMR spectra could be recorded for these species. Treatment of the S-phenylthiiranium ion with an alkene leads to a stow transfer of the sulfenium group at 0 degrees C. However, the S-methylthiiranium ion did not transfer the sulfenium group, even at room temperature. On the other hand, both the Se-phenyl- and Se-butylseleniranium ions transferred the selenenium moiety instantaneously at -70 degrees C. By measuring the equilibrium position for these transfers from both directions, the relative stability of the 1-phenylseleniranium ions could be established: cis-tetramethylene < trans-2,3-dipropyl similar to trans-2,3-diisopropyl < cis-hexamethylene.