A simple and convenient method for the synthesis of cyclobutenediones from alkynes using new Fe(CO)5/NaH/MeI reagent system

Iron carbonyl complexes prepared in situ using the Fe(CO)5/NaH/MeI reagent combination and alkynes at 25 °C give the corresponding cyclobutenediones in 50–65% yields after CuCl2 · 2H2O oxidation.

Reactive iron carbonyl species prepared using the readily accessible Fe(CO)5, NaH and MeI reagent combination upon reaction with alkynes followed by CuCl2 oxidation gives the corresponding cyclobutenediones in 50–65% yields.Figure optionsDownload as PowerPoint slide