Phthalonitrile was selected as the initial substrate for C-H alkylation as cyano-aryl species are a useful synthon in various electrochemical and photochemical transformations. , Cyanoarenes can also effectively stabilise aryl radicals/anions and thus are also common motifs in photocatalytic organic dyes. The visible-light absorbing EDA complex was constructed from redox active phthalimide esters and the electron rich tertiary amine donor DABCO, which has been selected as our donor (D) due to its known but under-utilised activation of redox active esters (RAEs). The RAEs were synthesised from a range of carboxylic acids, with the phthalimide redox auxiliary (RA) serving as the electron deficient component in the EDA complex. Upon complexation and photo-induced fragmentation, the irreversible loss of CO2 drives the reaction forward entropically, generating a phthalimide anion and a neutral alkyl radical (S • ). This alkyl radial can then selectively alkylate the C4 site of the electron deficient aromatic acceptor.