N‐Derivatives of peri‐Substituted Dichalcogenide [FeFe]‐Hydrogenase Mimics: Towards Photocatalytic Dyads for Hydrogen Production

Abstract

AbstractSynthetic strategies towards molecular dyads based on peri‐substituted dichalcogenide (S,Se) [FeFe]‐hydrogenase synthetic mimics covalently linked to a ZnTPP photosensitizer are described. Dithiolate and diselenolate model systems 2–5 are prepared through condensation of 2‐naphthaldehydes with p‐methoxyaniline, reduction of the resulting Schiff base and oxidative insertion of Fe2(CO)6 into the dichalcogen bond of the imine or amine. Diselenolate‐based [FeFe] complexes (imine 3 and amine 5) are more efficient in electrocatalysis of proton reduction than their sulfur analogues 2 and 4 with increasing concentrations of pTsOH. Molecular dyad 1 containing a peri‐substituted naphthalene dithiolate Fe2(CO)6 cluster covalently linked via an amine to ZnTPP is prepared through sequential zinc insertion into the porphyrin followed by iron insertion into the disulfide bond.