Alkenyl 1.1-dimetallic reagent

Allylzinc bromide is able to add to a variety of alkenyl Grignard reagents in THF at 35 °C123. The structure of the hydrocarbons 184, obtained in moderate yields after hydrolysis (due to their volatility), suggested that 1,1-dimetallic species tentatively formulated as 185 were regioselectively formed (equation 89). Additional examples were subsequently reported but the scope of this intriguing reaction remained rather unexplored and the reactivity of 185 towards various electrophiles was not investigated124,125. 

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