Donor-photosensitizer-acceptor triad

The construction of intramolecular molecular system whose photo active molecule linked with conducting molecular wire is an important subject in realization of. molecular electronic or photonic devices. For such objectives, systematization of donor-photosensitizer-acceptor triad molecules into large molecular systems is one of the feasible approaches because the exquisite incorporation of the photosensitizer and a suitable electron donor and/or acceptor into a conducting polymeric chain is useful for various molecular systems based on the photoinduced electron transfer. With this in mind, we synthesized symmetrical donor-acceptor-donor triad molecules which can be polymerized by the normal electrochemical oxidation. By the polymerization, one-dimensional donor-acceptor polymers with porphyrin moieties separated by ordered oligothienyl molecular wire which is considered as a proto-type molecular device was obtained. 

Sauvage J-P et al (1991) Photoinduced processes in dyads and triads containing a ruthe-nium(II) bis(terpyridine) photosensitizer covalently linked to electron-donor and acceptor groups. Inorg Chem 30 4230-4238... 

Molecular assembly 2, composed of a porphyrin chromophore covalently linked to a benzoquinone electron acceptor and a carotenoid polyene as electron donor provides an electron donor/photosensitizer/electron acceptor (D-S-A) configuration [34]. The sequential ET reactions occurring in the triad upon photoexcitation of the porphyrin center are outlined as follows (where C, P, and Q stand for the carotenoid polyene, porphyrin, and quinone components, respectively) ... 

VII. PHOTOINDUCED ELECTRON TRANSFER IN TRIAD CHROMOPHORE SEQUENCES OF (DONOR)-(POSSIBLE MEDIATOR)-(PHOTOSENSITIZER) AND (PHOTOSENSITIZER)-(POSSIBLE MEDIATOR)-(ACCEPTOR) LINKED TO A SINGLE a-HELICAL POLYPEPTIDE CHAIN... 

Mihara and co-workers have synthesized some interesting donor-acceptor maquettes that could be incorporated into bilayer membranes [105,106]. The first such system (88) consisted of a molecular triad in which a mthenium polypyridyl photosensitizer, an anthraquinone primary oxidant, and a propylviologen terminal acceptor were placed along the lengths of two amphiphilic 21-residue polypeptides that were covalently attached to the ruthenium template. Circular dichroism... 

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