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Here is a potential solution using old-school chemistry, though with several steps. Hydroborate the alkyne and work up with $\ce{H2O2}$ to give the aldehyde. Alkylate the aldehyde enolate with $\ce{RI}$, either directly (LDA or LiHMDS) or via enamine/silyl enol ether Reduce aldehyde to alcohol ($\ce{NaBH4/EtOH}$) Form triflate/mesylate and eliminate (DBU/...


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