Аннотация:Cyclopentadienes readily undergo fast and selective Diels-Alder reactions which can be used for conjugation of biomolecules and polymers. Herein we present a new method for the photochemical generation of cyclopentadienes by the visible light irradiation of the iron complexes [(C5H4R)Fe(arene)]+. This reaction proceeds at room temperature, in water, and in the presence of potentially interfering amino acids. Free cyclopentadiene is trapped by dienophiles to give the corresponding Diels-Alder adducts in 72-95% yields
