IClick cycloaddition reaction of light-triggered manganese(I) carbonyl complexes

Mono- and binuclear blue-light-induced CO-releasing molecules based on a fac-MnBr(CO)3 moiety and bearing benzimidazole ligands furnished with either a sulfonate or phosphonium group were synthesized. The effect of the ancillary ligand (Br− and NCS−) on the CO releasing properties was studied and compared with that of the triazolate complex synthesized by the free catalyst [3+2] cycloaddition iClick reaction. An extension of the iClick reaction to the binuclear complex was successful. The assignment of electronic transitions was done by TDDFT. The photoprocess of the binuclear complexes was faster than that of the mononuclear complex.