Bis-porphyrin arrays. Part 2.† The synthesis of asymmetrically substituted bis-porphyrins
作者:Richard Beavington、Paul L. Burn
DOI:10.1039/a907059a
日期:——
A strategy for the synthesis of asymmetrically substituted tetraazaanthracene linked bis-porphyrins in which the two porphyrin rings contain differences in their peripheral substituents has been developed. The method is illustrated by the preparation of bis-porphyrins with a single meso-halophenyl and seven meso-3,5-di-tert-butylphenyl substituents. The bis-porphyrins were prepared by condensation of a porphyrin-α-dione with benzene-1,2,4,5-tetraamine to form a porphyrin diaminoquinoxaline intermediate which was subsequently condensed with a second different porphyrin-α-dione. The key issue in the synthesis was the separation of the desired asymmetrically substituted bis-porphyrin from the symmetric bis-porphyrin by-products of similar polarities. Enhanced separation of the bis-porphyrin products was achieved by chelation of a metal into one of the porphyrin rings, the metal being introduced at the porphyrin-α-dione stage. Copper was successfully used when chelated into the less polar porphyrin-α-dione but the use of zinc in the more polar porphyrin-α-dione to enhance bis-porphyrin separation was unsuccessful as the pyridinium hydrochloride produced in the reaction was found to demetallate the porphyrins.
Tetrathiafulvalene-Fused Porphyrins via Quinoxaline Linkers: Symmetric and Asymmetric Donor-Acceptor Systems
作者:Hongpeng Jia、Belinda Schmid、Shi-Xia Liu、Michael Jaggi、Philippe Monbaron、Sheshanath V. Bhosale、Shadi Rivadehi、Steven J. Langford、Lionel Sanguinet、Eric Levillain、Mohamed E. El-Khouly、Ysushi Morita、Shunichi Fukuzumi、Silvio Decurtins
DOI:10.1002/cphc.201200350
日期:2012.10.8
calculations elucidate the nature of the electronically excited states. The compounds are electrochemicallyamphoteric and primarily exhibit low oxidation potentials. Cyclic voltammetric and spectroelectrochemical studies allow differentiation between the TTF and porphyrin sites with respect to the multiple redox processes occurring within these molecular assemblies. Transient absorption measurements give
Beavington, Richard; Rees, Philip A.; Burn, Paul L., Journal of the Chemical Society. Perkin transactions I, 1998, # 17, p. 2847 - 2851
作者:Beavington, Richard、Rees, Philip A.、Burn, Paul L.
DOI:——
日期:——
A new synthetic approach to porphyrin-α-diones and a -2,3,12,13-tetraone: building blocks for laterally conjugated porphyrin arrays
作者:Vinich Promarak、Paul L. Burn
DOI:10.1039/b007389j
日期:——
We report the first use of the Dess–Martin periodinane (DMP) for the oxidation of an arylamine to an α-dione. The methodology is illustrated by the preparation of free-base and metal chelated porphyrin-α-diones in up to 52% yield by oxidation of 2-aminoporphyrins with the DMP. We also found that DMP could be used to oxidise a 2,3-diaminoporphyrin to a porphyrin-α-dione in good yield with other free-base
Construction of building blocks for extended porphyrin arrays by nitration of porphyrin-2,3-diones and quinoxalino[2,3-b]porphyrins
作者:Maxwell J. Crossley、Craig S. Sheehan、Tony Khoury、Jeffery R. Reimers、Paul J. Sintic
DOI:10.1039/b712643c
日期:——
difficult to separate, allows for highly selective remetalation of the 7-isomer and its very easy separation from the unmetalated 12-nitro-porphyrin-dione. These nitrated compounds are useful buildingblocks for more elaborate systems.