γ-seleno-α,β-ethylenic esters, when treated with sulfuryl chloride and ethyl vinyl ether in hexanes, produced α-chloro-β,γ-ethylenic esters in 65−75% yields, with ee values of 95−97%, and with 1,3-syn transfer of chirality. Reaction of these allylic chloride electrophiles with methylcuprate and with sodium azide nucleophiles afforded exclusively γ-substituted-α,β-ethylenic esters with faithful anti-transfer
                                    手性非外消旋的γ-
硒代-α,β-烯键式酯,在己烷中用
硫酰氯和乙基
乙烯基醚处理后,以65-75%的产率产生α-
氯-β,γ-烯键式酯,ee值为95-97 %,并具有1,3-syn手性转移。这些烯丙基
氯亲电试剂与甲基
铜酸酯和
叠氮化
钠亲核试剂反应,仅得到γ-取代的-α,β-烯键式酯,在毫克数级上具有可靠的手性抗转移性。