69082-94-6Relevant academic research and scientific papers
Influence of meso-linker attachment on the formation of coreπ interactions in urea-functionalized porphyrins
Flanagan, Keith J.,Ryan, Aoife A.,Twamley, Brendan,Senge, Mathias O.
, p. 755 - 764 (2020)
The ability to cover the face of a porphyrin macrocycle selectively is an attractive feature for concepts such as catalysis and anion binding that is reliant on porphyrin core interactions. Herein, we have synthesized a family of mono-urea functionalized porphyrin complexes with intent to investigate their potential to form coreπ interactions selectively to one face of the porphyrin macrocycle. By altering the distance between the urea moiety and the porphyrin through direct linkage or introducing a linker group we can control the formation of the core interactions. This is clearly seen in the crystal structure of 1-phenyl-3-(2-([10,15,20-triphenylporphyrinato]zinc(II)-5-yl)phenyl)urea where a unique face capping effect is demonstrated. In the crystal of this complex, there is a hydrogen-bonding network between the urea group and the axial methanol ligand forming head-to-tail aggregates with the Zn-O axis all molecules pointing in one direction.
The NMR Spectra of the Porphyrins. 24 - The NMR Spectra of some Tetraarylchlorins
Abraham, Raymond J.,Plant, James E.
, p. 745 - 756 (1983)
The synthesis and complete assignment of the 1H NMR spectra of 5-(o-pivaloylaminophenyl)-10,15,20-triphenylporphyrin (PIVTTP) and its two chiral dihydro adducts 3,4-dihydro-(PIVPTPC-I)- and 7,8-dihydro-(PIVPTPC-II)-porphyrins are reported.The use of the zinc complexes of the chlorins as chiral shift reagents with optically active bases is discussed.Comparison of the observed shift differences between the chlorins and the parent porphyrin with those calculated by a ring current model shows that a decrease in the ring current occurs on chlorin formation, and also specific effects occur at the reduced pyrrole ring, presumably reflecting different steric constraints.
Through-Space Electrostatic Interactions Surpass Classical Through-Bond Electronic Effects in Enhancing CO2 Reduction Performance of Iron Porphyrins
Khadhraoui, Asma,Gotico, Philipp,Leibl, Winfried,Halime, Zakaria,Aukauloo, Ally
, p. 1308 - 1315 (2021/02/05)
In his pioneering work to unravel the catalytic power of enzymes, Warshel has pertinently validated that electrostatic interactions play a major role in the activation of substrates. Implementing such chemical artifice in molecular catalysts may help impr
Positional effects of second-sphere amide pendants on electrochemical CO2 reduction catalyzed by iron porphyrins
Nichols, Eva M.,Derrick, Jeffrey S.,Nistanaki, Sepand K.,Smith, Peter T.,Chang, Christopher J.
, p. 2952 - 2960 (2018/03/23)
The development of catalysts for electrochemical reduction of carbon dioxide offers an attractive approach to transforming this greenhouse gas into value-added carbon products with sustainable energy input. Inspired by natural bioinorganic systems that fe
A mild, facile, one-pot synthesis of zinc azido porphyrins as substrates for use in click chemistry
Bryden, Francesca,Boyle, Ross W.
supporting information, p. 1978 - 1982 (2013/09/24)
The conversion of porphyrins bearing primary amines into zinc-protected azido porphyrins utilising a diazo-transfer reagent is reported. This method allows the mild, facile, and one-pot synthesis of zinc azido porphyrins bearing a range of meso functionalities, producing the required porphyrin in high yield. Reactivity of the azide functionality is demonstrated by subsequent model click reactions to produce triazole derivatives. Georg Thieme Verlag Stuttgart New York.
L-nipecotic acid-porphyrin derivative: A chiral host with introverted functionality for chiral recognition
Wu, Xiaowen,Starnes, Stephen D.
body text, p. 3652 - 3655 (2012/09/08)
The synthesis and chiral recognition properties of a porphyrin host with introverted functionality is reported. The host is a hybrid of tetraphenyl zinc porphyrin and the N-phenylamide derivative of (S)-nipecotic acid. The chiral recognition properties of
Enhanced shape-selective recognition of anion guests through complexation-induced organization of porphyrin hosts
Wienkers, Marijo,Ramos, Josmalen,Jemal, Hikma,Cardenas, Chaz,Wiget, Paul,Nelson, Alfreda,Free, Shiloh,Wu, Jun,Roach, Rebecca,Vulcan, Marius,Waynant, Kristopher,Fort, Kyle,Vladimirova, Anna,Sun, Jeffery,Hunt, Samuel Eli,Rudkevich, Dmitry M.,Starnes, Stephen D.
body text, p. 1370 - 1373 (2012/05/20)
We present a fortuitous discovery of enhanced shape-selective recognition of anion guests that stems from a complexation-induced conformational change in porphyrin hosts upon anion binding. Porphyrin hosts reported here exist in a conformation that is not
A glycyl-substituted porphyrin as a starting compound for the synthesis of a π-π-stacked porphyrin-fullerene dyad with a frozen geometry
Lembo, Angelo,Tagliatesta, Pietro,Cicero, Daniel,Leoni, Alessandro,Salvatori, Alisa
supporting information; experimental part, p. 1093 - 1096 (2009/05/30)
A synthetic route for obtaining a porphyrin-fullerene dyad with a constrained geometry forcing the [60]fullerene sphere to lie on the porphyrin plane is reported, revealing a strong interaction in the ground state between the two chromophores. The Royal S
Simple heme dimers with strongly cooperative ligand binding
Khvostichenko, Daria,Yang, Qing-Zheng,Boulatov, Roman
, p. 8368 - 8370 (2008/09/19)
(Graph Presented) Two is better than one: FeII complexes of new porphyrins exist as dinners that bind small ligands cooperatively, as illustrated by the sigmoidal binding curve (fractional occupancy of binding sites, a, versus free-ligand conce
Synthesis and Characterization of Novel Flavin-Linked Porphyrins. Mechanism for Flavin-Catalyzed Inter- and Intramolecular 2e/1e Electron-Transfer Reactions
Takeda, Jun,Ohta, Shigeru,Hirobe, Masaaki
, p. 7677 - 7688 (2007/10/02)
The synthesis of several flavin-linked porphyrins is described.The two moieties (FloxCn(TPP)M, M=H2 and MnIIICl) are covalently linked by an amide linkage with a methylene spacer group n, n=1-3> between the ortho position of (o-aminophenyl)triphenylporphyrin and the N3 or N10 positions of the flavin.The FloxCn(TPP)M (1a-e) were characterized by UV-visible, 1H NMR, and IR spectra.The proximity conformation of the flavin and porphyrin ring was demonstrated by 1H NMR studies of FloxCnTPPH2.The electrochemistry of FloxCn(TPP)M was investigated by cyclic voltammetry and differential-pulse polarography.Cyclic voltammetry demonstrated that the flavin reduction potentials, Flox + e- = Fl.- and Fl.- + e- = Fl2-, were positively shifted by the proximity of the linked porphyrin moiety.Flavin-catalyzed 2e/1e electron-transfer reactions from dihydropyridines to (TPP)MnIIICl have been investigated kinetically in intermolecular systems (PyH2 + Flox + (TPP)MnIIICl) as well as in intramolecular systems (PyH2 + FloxCn(TPP)MnIIICl) in ethanol solution.In intermolecular systems, the presence of flavin enhances the apparent rates of electron transfer significantly.The kinetic behavior of the intermolecular system is zero order with respect to the (TPP)MnIIICl concentration and first order with respect to the PyH2 and Flox concentrations, when PyH2 is in excess and Flox is used in 0.25-1.5-fold to (TPP)MnIIICl.These observations indicate that the flavin acts as 2e/1e catalyst.In intramolecular systems, the kinetic behavior differs for the various FloxCn(TPP)MnIIICl systems.Whereas FloxC1(TPP)MnIIICl shows clean first order, FloxC2(TPP)MnIIICl and FloxC3(TPP)MnIIICl exhibit a mixed-order behavior.The apparent second-order rate constants are increased for the intramolecular systems.The rate enhancements by the intramolecular effect are as follows: kintra/kinter = 8.0 (1a), 3.9 (1b), 2.1 (1c), 1.7 (1d), and 1.8 (1e).These results show that the kintra/kinter values are affected by the methylene spacer length and the linking position.Possible reasons for the rate enhancement are discussed by using electrochemical data, conformational data, and kinetic isotope effects.The proposed reaction mechanism for the intramolecular system, especially for FloxC1(TPP)MnIIICl, involves a ternary complex such as ox...(TPP)MnIIICl>.The described systems are relavant models for biological electron-transfer processes requiring flavin 2e/1e catalysis and for flavin-heme interaction as in flavohemoproteins.
