Tandem chain extension–iodomethylation reactions: formation of α-functionalized γ-keto carbonyls

Sequential exposure of a zinc-organometallic intermediate, generated through a zinc carbenoid-mediated chain extension reaction of a β-keto carbonyl, to trimethylsilylchloride and iodine provided regioselective formation of an α-iodomethyl-γ-keto carbonyl. The iodomethyl functionality can be further manipulated to provide side chains that are potential mimics of α-amino acid side chains.