A two component coupling of an allene and an activated olefin to form 1, 3-dienes has been developed. The requisite allenes are synthesized either from terminal alkynes by a one carbon homologation using copper (I) iodide, paraformaldehyde, and diisopropylamine, via an ortho ester-Claisen rearrangement from a propargylic alcohol, or via a Wittig type reaction on a ketene generated in situ from an acid chloride. Mono-through ...
