Reactions and characterization of allylic and related zirconium reagents (allenic and γ-alkoxyallylic zirconiums) generated by treatment of allylic and/or propargylic ethers with a zirconocene-butene complex (“Cp2Zr”) are described.
Allenic samariumcomplexes are readily generated in high yields by the reaction of propargylic benzyl ethers with (C5Me5)2Sm(thf)2. Electrophilic trapping of the complexes derived from the secondary and tertiary ethers with cyclohexanone and dimethylphenylsilyl chloride gives the corresponding propargylic products selectively, whereas α-allenic alcohols are predominantly obtained in the reaction of
通过炔丙基苄基醚与(C 5 Me 5)2 Sm(thf)2的反应,可以容易地高收率生成烯丙基sa络合物。仲和叔醚衍生的配合物与环己酮和二甲基苯基甲硅烷基氯的亲电捕集选择性地产生相应的炔丙基产物,而α-烯丙醇主要是由伯醚生成的配合物与环己酮反应而获得的。
Preparation and reactions of allenic zirconium species from propargylic ether derivatives
The generation of allenic zirconium intermediates by treating propargylic ether derivatives with ''Cp2Zr'' and their reactions with aldehydes in the presence of borontrifluoride etherate yield anti-beta-acetylenic alcohols along with alpha-allenic alcohols.