Pre-formed phenyliodonium ylides of cyclic and acyclic βdiketones, β-keto esters and β-diesters were reacted with (dichloroiodo)benzene, resulting in transfer of both chloride ligands onto the ylidic carbon. These two hypervalent iodine(III) compounds exhibit high reactivity towards each other under mild reaction conditions and typically afford the gem-dichloride products in good yield. Upon comparison of these chlorination reactions with those of the analogous diazocarbonyl compounds, reactions of iodonium ylides were unilaterally faster, and often gave the products in higher yield.

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