Iron-Catalyzed [2+2+2] Cycloaddition Reactions of Diynes with Oxyphosphaethynes To Construct 2-Phosphaphenol Derivatives

Iron-catalyzed [2 + 2 + 2] cycloaddition reactions of diynes with siloxyphosphaethynes have been developed to give 2-phosphaphenol derivatives. The use of electronically neutral siloxyphosphaethynes generated in situ by the reaction of anionic phosphaethynolate with silyl triflates is key to achieving the reactions.