Stereoselective Synthesis of Medium-sized Carbocyclic Compounds by Tandem Reactions of Cyclic Sulfur Ylides

五元氧基磺酰化物与Baylis - Hillman加合物的乙酸酯反应，通过Michael - Corey - chaykovsky串联反应得到立体选择性高的环氧环庚烯衍生物，产率为19- 74%。所得化合物的立体化学性质通过x射线分析得到了证实。从立体化学的结果来看，分子内的Corey反应是通过含有椅子型硫环己烷环的刚性双环中间体进行的。此外，还研究了相应的六元硫醚的相同反应。因此，环氧环烯衍生物的产率为7- 46%，与硫原子构型相关的非对映体的混合物为4:1。此外，还尝试了环硫醚与醛类和烯酮的反应，以评价其反应活性。所有的反应都能以优异的收率生成Corey反应产物（环丙烷或氧烷衍生物）。另一方面，六元氧磺基吡啶与4-己烯-2- 1在两个等摩尔碱的存在下反应，得到了一种新型的具有高立体选择性的八元碳环化合物（吡啶与烯酮的1:1加合物）。

The reaction of a five-membered oxosulfonium ylide with acetates of Baylis - Hillman adducts afforded cycloheptene oxide derivatives with high stereoselectivity in 19-74 % yields via tandem Michael - intramolecular Corey -Chaykovsky reactions. The stereochemistry of resulting compounds was elucidated by an X-ray analysis. From the results of the stereochemistry, an intramolecular Corey reaction was implied to proceed via a rigid bicyclic intermediate containing a chair-form thiacyclohexane ring. In addition, the same reaction of the corresponding sixmembered sulfur ylide was investigated. Consequently, cyclooctene oxide derivatives were obtained in 7-46 % yields as a 4 : 1 mixture of diastereomers relevant to the configuration of sulfur atom. Moreover, the reactions of the cyclic sulfur ylides with aldehydes and enones were attempted in order to evaluate the reactivity of cyclic sulfur ylides. All of the reactions provided the Corey reaction products ( cyclopropane or oxirane derivatives ) in excellent yields. On the other hand, the reaction of the six-membered oxosulfonium ylide with 4-hexen-2-one in the presence of two equimolar amount of base gave a novel eight-membered carbocyclic compound ( 1 : 2 adduct of ylide and enone ) with high stereoselectivity.