CO-Preserving Photoinduced Transfer of Cymantrenyl Moiety: a Tandem Experimental and Computational Investigation.

Cyclopentadienyl manganese tricarbonyl (cymantrene) is known to undergo photochemical reactions by releasing one of its CO ligands. Here we present the first example of a photorearrangement of a cymantrenylmethyl fragment, where it retains all its three CO ligands. A tandem experimental and DFT (density functional theory)-based computational investigation allows us to explain this unexpected behavior: the rearrangement, indeed, begins with the release of one CO ligand, but cage effect of the solvent captures this CO molecule, allowing it to rapidly reattach once the rearrangement takes place. [ABSTRACT FROM AUTHOR]