环戊烯基甲基,环己烯基甲基和α-pin烯基钴肟与芳烃磺酰卤的光刺激反应导致相应的外亚甲基环烷基砜的形成,分离产率为82-98%。通过自由基链机理使产物形成合理化,所述自由基链机理涉及通过磺酰基从有机钴肟中置换出钴肟(II)的S H 2'。然而,在热条件下的反应提供了exo-亚甲基环烷基砜及其内异构体的混合物。独立实验证实,内源异构体是由外源异构体的1,3-烯丙基容易重排产生的。从力学和理论研究,提出了重排涉及磺酰基的[1,3]-σ迁移。
thermodynamically-stable isomers is negligible. On the other hand, the palladium-catalyzed sulfonylation of allylic acetates with sodium benzenesulfinate is accompanied by the isomerization to give the thermodynamically-controlled products selectively. These results can be explained by assuming that allylic nitro compounds are more reactive to the palladium catalyst than allylic acetates and sulfones.
Regioselective synthesis of allylic sulfones by palladium-catalyzed denitro-sulfonylation of allylic nitro compounds
作者:Rui Tamura、Koji Hayashi、Masato Kakihana、Masanori Tsuji、Daihei Oda
DOI:10.1016/s0040-4039(00)61946-9
日期:1985.1
Allylicnitrocompounds undergo denitro-sulfonylation catalyzed by Pd(PPh3)4 or Pd(PPh3)4 +NaNO2 with PhSO2Na·2H2O to afford allylic sulfones regioselectively.
Palladium-catalyzed substitutions of allylic nitro compounds. Regiochemistry
作者:Rui Tamura、Yoshiki Kai、Masato Kakihana、Koji Hayashi、Masanori Tsuji、Tsunehiro Nakamura、Daihei Oda
DOI:10.1021/jo00373a008
日期:1986.11
Controlled endocyclic and exocyclic γ-metalations of β-substituted cyclohexenyl sulfones. Regiospecific syntheses of γ-oxygenated cyclohexenyl sulfones.
作者:S.W Lee、P.L Fuchs
DOI:10.1016/0040-4039(91)80632-g
日期:1991.6
Beta-Substituted cyclohexenyl sulfones may be regiospecifically isomerized to either endocyclic or exocyclic allyl sulfones. Epoxidation of these materials followed by a second metalation yields gamma-hydroxy cyclohexenyl sulfones 6 and 7. Subjection of either of these materials to a second oxidation/isomerization sequence smoothly provides the bis gamma-hydroxylated cyclohexenyl sulfone 10 in excellent overall yield.