Researchers from Professor Harry Anderson’s group, in collaboration with Professor Fernanda Duarte and Professor Laura Herz (Oxford Physics), and scientists from the University of Nottingham, have reported the synthesis of a 24-porphyrin ring that mimics the light-harvesting arrays of chlorophyll molecules responsible for photosynthesis.
They report the synthesis of a macrocycle in which meso-meso linked porphyrin rods have been bent into a ring. Oligomers of this type are known as “photonic wires” and they have long been regarded as rod-like. This is the first demonstration that molecular templates can bend them into rings. These nanorings exhibit two types of intramolecular energy migration: (a) from the central template to the peripheral ring of porphyrins and (b) from the 24 porphyrins to a butadiyne-linked segment of the nanoring. The kinetics of both processes have been characterised using ultra-fast time-resolved fluorescence spectroscopy. The second process is extremely fast and about 30% of the energy is transferred within the time-resolution of the experiment (350 fs). This is the first synthetic light-harvesting system to exhibit such fast energy migration on this length scale without π-conjugation between the component chromophores.
Read the full paper in Nature Chemistry.
Read the highlight in Chemical and Engineering News.