Fullerene derivatives have been the dominant electron acceptors in organic photovoltaics, but have limitations, including poor absorption in the visible to near-IR and limited tuning of the energy levels. There is strong interest in discovering new electron acceptors that may overcome these limitations. Our latest research in developing non-fullerene acceptors based on core-substituted naphthalene diimides and on azadipyrromethenes is presented. 2,6-dialkylamino core-substituted naphthalene diimides are good candidates for OPVs due to their strong absorption in the visible range and their high electron affinity. Efforts to further tune their properties through imide substitutions will be presented. Azadipyrromethenes are also promising building blocks for n-type optoelectronic materials because they are ligands with strong absorption in the visible to near-IR, high electron affinity, and tunable energy levels through substitutions and chelation with BF2+ or transition metals. New azadipyrromethenes with arylethynyl substituents were synthesized, characterized and coordinated with BF2+ and d10 transition metals. Testing in organic solar cells revealed that homoleptic zinc(II) complexes of azadipyrromethenes are promising non-planar electron accepting materials for organic photovoltaics.