Bimetallic alkenes have been proven to be versatile compounds for the formation of multi-functionalized valuable compounds through carbon-carbon and carbon-hetero atom bond formations by wisely choosing the coupling partners. Therefore, the transformation of bimetallic species that allow the introduction of diverse functionalities will be a highly demandable owing to the differential reactivities associated with them. In a careful consideration of these features and continuation of our recent research on temporary coordination of a neighboring sulfone group to a metal for stereoselectivity control, herein, we are presenting the results of a highly regio- and stereoselective copper-catalyzed hydroborylation of allensulfonamide with bis(pinacolato)diboron. The subsequent trapping of the intermediate by tri-n-butyltinmethoxide allowed a three-component coupling with same reactivity. Because of the equilibrium associated with this type of functionalized stannane alkenes, however, we observed the formation of only linear β-borylated allyltin under the same reaction condition. We also demonstrated the diverse transformations using these bimetallics compound to many interesting compounds.
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