Site Isolation Leads to Stable Photocatalytic Reduction of CO 2 over a Rhenium‐Based Catalyst

A porous organic polymer incorporating [(α‐diimine)Re(CO) 3 Cl] moieties was produced and tested in the photocatalytic reduction of CO 2 , with NEt 3 as a sacrificial donor. The catalyst generated both H 2 and CO, although the Re moiety was not required for H 2 generation. After an induction period, the Re‐containing porous organic polymer produced CO at a stable rate, unless soluble [(bpy)Re(CO) 3 Cl] (bpy=2,2′‐bipyridine) was added. This provides the strongest evidence to date that [(α‐diimine)Re(CO) 3 Cl] catalysts for photocatalytic CO 2 reduction decompose through a bimetallic pathway.