Generation of allenic samarium complexes from propargylic ethers and (C5Me5)2Sm(thf)2, and their electrophilic trapping

Article abstract of DOI:10.1016/0040-4039(95)01260-O

Allenic samarium complexes 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 the complexes, generated from the primary ethers, with cyclohexanone.