Synergistic meso-β regulation of porphyrins: squeezing the band gap into the near-infrared I/II region

A dual meso /β-substituent regulation strategy is reported for effective energy-gap narrowing of porphyrins. The complexes of meso -alkynyl naphthoporphyrins exhibit remarkable red-shifted near-infrared absorption/emission ranging from 800 to 1400 nm.