Identical Substituents Research Articles

Pegylated Viologen Derivatives to Improve Performance of Aqueous Organic Redox Flow Battery

Renewable energy sources like wind and solar power are great alternatives for a clean way to produce electricity but have the inconvenience to fluctuate1. To address this issue and promote the implementation of renewables sources, scientists are developing new ways to store energy while production is at a maximum for a subsequent release when there is demand. Redox flow batteries (RFBs) are the most appropriate solution and are increasingly gaining attention for stationary, large scale electrochemical energy storage2,3. One variation of RFBs are aqueous organic redox flow batteries (AORFBs), where water-soluble organic molecules are use as the redox couple. Viologen type molecules are particularly well-suited as a negative potential species to develop cheaper and better AORFBs with great scalability, reversibility and long-term stability4.In this study, viologen derivatives were synthesized with various N-functional groups to explore the impact of the substituent on their solubility, viscosity and redox potential. We showed that the use of short chains of poly(ethylene glycol) improved the solubility of the viologens derivatives which could lead to batteries with higher capacity. The symmetric viologen (with two identical substituents) provided a great solubility in water and the formal potential was unaffected by the chemical nature of the substituents. We demonstrated that the 1,1’-(bisethylene glycol)-4,4’-bipyridium (PEG2-V-PEG2) showed the most promising properties with a high solubility (2.3 M in 1M KCl) and low viscosity (3.01 mPa*s at 1M). As such, this derivative was selected for further evaluation in an asymmetrical labs-scale RFB prototype cell versus bis(trimethylamoniumpropyl)ferrocene (BTMAP-Fc). The compound was studied at various concentrations to assess the maximum energy density that can be reached and the effect of concentration on cycling life by achieving a comparison to the symmetrical 1,1’-bis(3-sulfonatopropyl)-4,4’-bipyridium (SPr-V-SPr) at 0.5 M. Figure 1: Redox flow battery scheme using Viologen derivative as the negolyte and BTMAP-Fc as the posolyte Reference Shi, X., Qian, Y. and Yang, S. Fluctuation analysis of a complementary wind–solar energy system and integration for large scale hydrogen production. ACS Sustainable Chemistry & Engineering, 8(18), pp.7097-7110. (2020)Sánchez-Díez, E.; Ventosa, E.; Guarnieri, M.; Trovò, A.; Flox, C.; Marcilla, R.; Soavi, F.;Mazur, P.; Aranzabe, E.; Ferret, R., Redox flow batteries: Status and perspective towards sustainable stationary energy storage. Journal of Power Sources, 481, 1-23. (2021)Poullikkas, A., A comparative overview of large-scale battery systems for electricity storage. Renewable and Sustainable energy reviews, 27, pp.778-788. (2013)Gentil, S., Reynard, D. and Girault, H.H. Aqueous organic and redox-mediated redox flow batteries: a review. Current Opinion in Electrochemistry, 21, pp.7-13. (2020) Figure 1

Synthesis of 9-(substituted phenoxycarbonyl)-10-methylacridinium trifluoromethanesulfonates: Effects of the leaving group on chemiluminescent properties.

Various 9-(substituted phenoxycarbonyl)-10-methylacridinium trifluoromethanesulfonates possessing electron-withdrawing substituents have been synthesized. The effect of substituents on the stability of the acridinium esters (AEs) at various temperatures in different buffers and the chemiluminescent properties have been examined. There was little correlation between the chemiluminescent properties of AEs and the pKa values of their associated phenols, but the steric effects of the ortho-substituents in the phenoxy group, as well as their electron-withdrawing natures, seem to play an important role in determining the properties. In general, when two identical substituents are present in the 2- and 6-positions, the compound is significantly more stable than when only a single substituent is present, presumably because of greater steric hindrance from the second group. The exception is the 2,6-difluorophenyl ester, which is less stable than the 2-fluorophenyl ester, presumably because the fluoro group is small. Addition of a third electron-withdrawing substituent at the 4-position, where it has no steric influence, typically increases susceptibility to decomposition. The presence of a nitro group has a significant destabilizing effect on AEs. Of the AEs studied, the 4-chlorophenyl ester showed the greatest chemiluminescent yield, while the 2-iodo-6-(trifluoromethyl)phenyl ester group showed the greatest stability in low pH buffers.

Synthesis of meta-carbonyl phenols and anilines

Phenols and anilines are of extreme importance for medicinal chemistry and material science. The development of efficient approaches to prepare both compounds has thus long been a vital research topic. The utility of phenols and anilines directly reflects the identity and pattern of substituents on the benzenoid ring. Electrophilic substitutions remain among the most powerful synthetic methods to substituted phenols and anilines, yet in principle achieving ortho- and para-substituted products. Therefore, the selective preparation of meta-substituted phenols and anilines is the most significant challenge. We herein report an efficient copper-catalyzed dehydrogenation strategy to exclusively synthesize meta-carbonyl phenols and anilines from carbonyl substituted cyclohexanes. Mechanistic studies indicate that this transformation undergoes a copper-catalyzed dehydrogenation/allylic hydroxylation or amination/oxidative dehydrogenation/aromatization cascade process.

Vibrational analysis, frontier orbitals, optical and structural properties of 1, 2-dithiete and di-thiolene derivatives: A quantum mechanical study

The organic chemistry of sulfur-containing compounds has attracted much research due to its importance in biology, biochemistry, and various industries. 1, 2-Dithiete is a cyclic and unsaturated organo-sulfuric compound. This compound can be converted to di-thiolene (its valence isomer). The structure, electronic properties, and energy of two valence isomers, i.e. di-thiolene and 1,2-dithiete (III) were studied using density functional theory (DFT). Results showed that di-thiolene has two conformers (s-trans (I), s-cis (II)) and the s-trans is more stable. The electron donor and acceptor substituents on the carbon atoms increase the polarity difference between these two valence isomers. The dipole moment and polarizability of di-thiolenes were also greater than those of 1, 2-dithietes. Conversion of 1,2-dithiete to di-thiolene, structural properties, polarity, and polarizability of some derivatives of these two valence isomers were examined by quantum mechanical method at the level of B3LYP theory and 6-311++g (d, p) bases sets using Gaussian09 computational program. This conversion occurs through the s-cis conformation pathway and is an exothermic reaction. In the cases of ten derivatives of C2S2R2 (R = CH3, CF3, CN, OCH3, CH2CH3, t-Bu, Ph, Cyclopropyl, Cyclobutyl, and Cyclopentyl) the s-cis conformers are so unstable that they are not obtained as local structures. In general, s-trans di-thiolenes are more stable than their cyclic valence isomers (1,2-dithietes). Of course, the degree of stability depends on substituent identity.

Pathway-dependent supramolecular polymerization by planarity breaking.

In controlled supramolecular polymerization, planar π-conjugated scaffolds are commonly used to predictably regulate stacking interactions, with various assembly pathways arising from competing interactions involving side groups. However, the extent to which the nature of the chromophore itself (planar vs. non-planar) affects pathway complexity requires clarification. To address this question, we herein designed a new BOPHY dye 2, where two oppositely oriented BF2 groups induce a disruption of planarity, and compared its supramolecular polymerization in non-polar media with that of a previously reported planar BODIPY 1 bearing identical substituents. The slightly non-planar structure of the BOPHY dye 2, as evident in previously reported X-ray structures, together with the additional out-of-plane BF2 group, allow for more diverse stacking possibilities leading to two fiber-like assemblies (kinetic 2A and thermodynamic 2B), in contrast to the single assembly previously observed for BODIPY 1. The impact of the less rigid, preorganized BOPHY core compared to the planar BODIPY counterpart is also reflected in the stronger tendency of the former to form anisotropic assemblies as a result of more favorable hydrogen bonding arrays. The structural versatility of the BOPHY core ultimately enables two stable packing arrangements: a kinetically controlled antiparallel face-to-face stacking (2A), and a thermodynamically controlled parallel slipped packing (2B) stabilized by (BF2) F⋯H (meso) interactions. Our findings underscore the significance of planarity breaking and out-of-plane substituents on chromophores as design elements in controlled supramolecular polymerization.

Rhodium-Catalyzed Alkenylation of Arenes with Multi-Substituted Olefins: Comparison of Selectivity and Reaction Rate as a Function of Olefin Identity

Rhodium-catalyzed arene alkenylation using Cu(II) carboxylates as the in situ oxidant and mono-substituted olefins has been previously reported (e.g., J. Am. Chem. Soc. 2019, 139, 5474; J. Am. Chem. Soc. 2018, 140, 17007; Organometallics 2019, 38, 3860; J. Am. Chem. Soc. 2020, 142, 10534). Herein, studies are extended to multi-substituted olefins with the goal of evaluating the effect of olefin substitution pattern and substituent identity on selectivity and turnover frequency. The influence of olefin substitution is probed by comparing the conversion of benzene to alkenyl arenes with ethylene, propylene, 1-butene, cis-2-butene, trans-2-butene, isobutene, 2-methyl-2-butene, and tetramethylethylene as well as the phenyl-substituted olefins and isomers of propenylbenzene. The rate of oxidative hydrophenylation for multi-substituted olefins follows the trend monosubstituted > disubstituted > trisubstituted, and tetrasubstituted olefins are unreactive. To probe the effect of substituent size on Markovnikov/anti-Markovnikov regioselectivity, cyclohexyl, tert-butyl, isopropyl, ethyl, and methyl substituted α-olefins are compared. Selectivity for anti-Markovnikov products generally increases as substituent steric bulk is increased. Tolerance for some functionalized olefins is demonstrated. The ortho/meta/para regioselectivity with mono-substituted arenes reveals that arene and olefin identity influences selectivity. Further mechanistic studies provide evidence for Curtin–Hammet control of ortho/meta/para regioselectivity with monosubstituted arenes.

Effect of alkyloxy substituents on mesomorphic and photophysical properties of star-shaped tristriazolotriazines

ABSTRACTTwo series of tristriazolotriazine (TTT) derivatives with different length of aliphatic substituents have been synthesised in order to study the influence of peripheral substitution on mesomorphism and fluorescent properties of these star-shaped compounds. Homologues with methoxy and alkyloxy substituents (series 1) are non-mesogenic, in contrast to homologues with two alkyloxy substituents (series 2) exhibiting columnar mesophase. The results obtained by quantum-chemical calculations for the monomers and dimers of non-mesogenic TTT series and their comparison with truxenone derivatives having identical substituents made it possible to establish the reasons that deprive series 1 of mesogenity. Compounds of both TTT series possess good solubility in organic solvents and capable of specific interactions with solvents in the ground and excited states. They form fluorescenting floating layers and thin films. An analysis of the fluorescence spectra showed a high potential for their application, in particular, in the field of molecular sensing and precise non-invasive control.

The Impact of a 1,2,3-Triazole Motif on the Photophysical Behavior of Non-K Tetrasubstituted Pyrene with a Substitution Pattern Providing the Long Axial Symmetry.

1,3,6,8-Tetrasubstituted pyrene derivatives with two types of substituents (4-(2,2-dimethylpropyloxy)pyridine, 1-decyl-1,2,3-triazole, 1-benzyl-1,2,3-triazole, and pyrazole), substituted in such a way that provides the long axial symmetry, are prepared and characterized in the present study. To the best of our knowledge, the pyrene derivative containing the same heteroaryl motif (triazole) but substituted by two various alkyls, straight decyl and benzyl-based side chains (C), is reported for the first time. For comparison, compounds with one kind of triazole motif and substituted pyridine or pyrazole groups were prepared (A and B). The photophysical properties of all molecules were evaluated by thermogravimetric analysis (TGA) and UV-Vis spectroscopy (absorption and emission spectra, quantum yields, and fluorescence lifetimes). The obtained results were compared to analogues substituted at the 1,3,6,8 positions by one kind of substituent and also with all the 1,3,6,8-tetrasubstituted pyrenes reported in the literature substituted by two kinds of substituents with a substitution pattern that provides long axial symmetry. In addition, theoretical studies based on DFT and TD-DFT were performed that supported the interpretation of the experimental results. The photophysical properties of tetrasubstituted pyrene derivatives having triazole units at the 1,8-positions, respectively, and other identical substituents at the 3,6 positions show the dominance of triazole units in the pyrene framework; the dominance is even higher in the case of the substitution of 1,3,6,8 positions by triazoles, but containing two various alkyls.

Tuning the dual emission of keto/enol forms of excited-state intramolecular proton transfer (ESIPT) emitters via intramolecular charge transfer (ICT)

Herein disclosed the adjustment of the dual emission of keto and enol forms of excited-state intramolecular proton transfer (ESIPT) emitters via intramolecular charge transfer (ICT) effects. Introducing electron-donating triphenylamine (TPA) and electron-withdrawing triphenylboron (TPB) substituents into the para-position of the phenolic hydroxyl group or the side of the oxazole of 2-(2′-hydroxyphenyl)oxazole skeleton endows the resulting compounds (6a-6d) with different photophysical properties. Owing to the ICT effect from electronic donor to acceptor, introducing TPA into the side of oxazole and TPB into the para-position of phenolic hydroxyl is conducive to an enol-form emission (6a). Exchanging the two substituents, namely introducing TPB into the side of oxazole and TPA into the para-position of phenolic hydroxyl, would be beneficial to a keto-form emission (6b). Synchronously introducing two identical substituents, whether TPA or TPB, into two sides of 2-(2′-hydroxyphenyl)oxazole skeleton (6c and 6d) would lead to the dual emission of keto and enol forms due to the excited-state equilibrium of ESIPT reactions, which are further verified by DFT calculation. The organic light-emitting diode (OLED) devices with 6a and 6c as emitters were fabricated, both of which exhibit hybridized local and charge transfer (HLCT) excited-state characters with high external quantum efficiencies (EQEs) of 4.9% and 5.6%, respectively.

Sensing and Catalysis Using Functionalized Oxoporphyrinogens

Simple oxoporphyrinogen (OxP) derivatives are excellent colorimetric sensors for a variety of analytes including anions, acidity and enantiomeric excess. More recently, this family of compounds has grown to include rim-functionalized compounds, which also exhibit colorimetric properties. In this work, we have prepared differently rim-functionalized OxPs and we will present their properties with respect to sensing, including selective anion binding, ion pair sensing andcoupled sensing of other important polluting species. The sensing properties of OxPs rely on intermolecular hydrogen bonding interactions which, in turn, imply their possible applications in organocatalysis. These properties will be described with an emphasis on the identity of macrocyclic substituents, and how catalytic activity of the OxP macrocycles is established. Structural aspects of OxPs influencing their sensing and organocatalytic activities will be discussed.

Влияние новых водорастворимых производных фуллерена C60, имеющих одинаковые заместители и одну замену CL→ME на экспрессию генов и активность транскрипционных факторов NRF2 и NFkB

С применением новых наносоединений, в частности, производных фуллерена С60, возрастает вероятность контакта с ними человека. Показано, что водорастворимые производные фуллерена могут влиять на транскрипционную активность генов в эмбриональных фибробластах легких человека (ФЛЭЧ). Активация транскрипционного фактора NFkB (nuclear factor kappa-light-chain-enhancer of activated B cells) индуцирует процессы, направленные на выживание клеток, а также развитие провоспалительного ответа. Экспрессия генов, обеспечивающих защиту от стресса на клеточном уровне, запускается фактором транскрипции, NRF2 (nuclear factor [erythroid-derived 2]-like factor 2). Взаимодействие между NFkB и NRF2 в основном носит характер антагонизма. Поиск новых соединений, избирательно активирующих транскрипционный фактор NFkB и NRF2, остаётся актуальной задачей современной медицины. With the use of new nanocompounds, in particular, derivatives of fullerene C60, the likelihood of human contact with them increases. It has been shown that water-soluble derivatives of fullerene can affect the transcriptional activity of genes in human embryonic fibroblasts of the lungs (PLEC). Activation of the transcription factor NFkB (nuclear factor kappa-light-chain-enhancer of activated B cells) induces processes aimed at cell survival, as well as the development of a pro-inflammatory response. The expression of genes that provide protection against stress at the cellular level is triggered by a transcription factor, NRF2 (nuclear factor [erythroid-derived 2] -like factor 2). The interaction between NFkB and NRF2 is mainly antagonistic. The search for new compounds that selectively activate the transcription factor NFkB and NRF2 remains an urgent task of modern medicine.

Sensing and Catalytic Properties of Oxoporphyrinogens

Simple oxoporphyrinogen (OxP) derivatives are excellent colorimetric sensors for a variety of analytes including anions, acidity and enantiomeric excess. More recently, this family of compounds has grown to include rim-functionalized compounds, which also exhibit colorimetric properties. In this work, we have prepared differently rim-functionalized OxPs and we will present their properties with respect to sensing, including selective anion binding, ion pair sensing and coupled sensing of other important polluting species. The sensing properties of OxPs rely on intermolecular hydrogen bonding interactions which, in turn, imply their possible applications in organocatalysis. These properties will be described with an emphasis on the identity of macrocyclic substituents, and how catalytic activity of the OxP macrocycles is established. Structural aspects of OxPs influencing their sensing and organocatalytic activities will be discussed.

Substituent-dependent reactivity of triarylantimony(iii) toward I2: isolation of [Ar3SbI]+ salt

The outcome of reactions of triarylantimony (Ar3Sb) with diiodine in benzene is strongly affected by the identity of the substituents.

Ru(II) coordination compounds of N[sbnd]N bidentate chelators with 1,2,3 triazole and isoquinoline subunits: Synthesis, spectroscopy and antimicrobial properties

Bidentate chelators 1-(1-benzyl-1,2,3-triazol-4-yl)isoquinoline and 3-(1-benzyl-1,2,3-triazol-4-yl)isoquinoline were prepared from benzyl bromide and trimethylsilylethynylisoquinoline precursors using a tandem deprotection/substitution/CuAAC synthetic approach. Each chelator is capable of forming a stable 3:1 Ru(II) coordination compound, which forms as a geometric isomer mixture. These Ru(II) complexes possess unique MLCT absorbance signatures at 450/472 nm (1-isomer) and 367 nm (3-isomer) relative to their constituent chelating units. Minimum inhibitory concentration values as low as 0.4 μM are observed for Ru(II) complexes against representative Gram-positive bacteria Bacillus subtilis and Staphylococcus epidermidis. Comparing the MIC values of these isoquinoline compounds with analogous 2-(1-benzyl-1,2,3-triazol-4-yl)pyridine compounds shows a 2.5- to 40-fold improvement in potency. This study establishes that increased hydrophobicity introduced at the central chelating units of Ru(II) coordination compounds can be a useful means by which to optimize antimicrobial activity that is complimentary to the variation of peripheral substituent identity at the chelator’s N1 triazole position.

Axial chirality inversion at a spiro carbon leads to efficient synthesis of polyimine macrocycle

The synthesis and conformational preferences of a novel chiral macrocyclic polyimine possessing spiro carbon atoms is described. The key feature of the synthesis is the incorporation of an axially chiral surrounding of quaternary carbon atom having four constitutionally identical substituents into the structure of the macrocycle. This is possible by partial hydrolysis, which enables the inversion of absolute configuration, of the spiro-acetal moiety. This approach allows to obtain the macrocyclic product with almost quantitative yield. The synthesis of rhombimine with enantiopure trans -1,2-diaminocyclohexane and racemic bisaldehyde with spiro carbon atoms yields single macrocyclic product with almost quantitative yield. This is possible by partial reverse hydrolysis and thus ring opening and the inversion of absolute configuration of the a conformationally stable spiro-acetal moiety. • Diastereoselective synthesis of spiro rhombimines. • Absolute configuration of spiro moiety changes during the reaction. • New mechanism for adapting the racemic substrate in the macrocyclization reaction.

Crystal Structures of Cobalt Sandwich Complexes in the η5-Cyclopentadienyl/η4-Cyclobutadiene and η5-Cyclopentadienyl/η4-Cyclopentadienone Families

The crystal structures of six cobalt sandwich complexes—four in the η5-cyclopentadienyl/η4-cyclobutadiene family, two from the related η5-cyclopentadienyl/η4-cyclopentadienone family—are presented and discussed alongside related structural precedents. In each of the complexes an undecorated cyclopentadienyl ligand is present whereas the partner cyclobutadiene or cyclopentadienone ligand bears four identical aromatic substituents (phenyl, p-tolyl, p-fluorophenyl, 2-thienyl or 2,2′-bithienyl). This range of substituents allows for detailed structural comparison between members of the families of sandwich complexes presented here, and with previously reported structures. Crystal structures of members of the η5-cyclopentadienyl/η4-tetraarylcyclobutadiene (left) and η5-cyclopentadienyl/η5-cyclopentadienone (right) families of sandwich complexes are presented.

Antimicrobial Photodynamic Polymeric Films Bearing Biscarbazol Triphenylamine End-Capped Dendrimeric Zn(II) Porphyrin.

A novel biscarbazol triphenylamine end-capped dendrimeric zinc(II) porphyrin (DP 5) was synthesized by click chemistry. This compound is a cruciform dendrimer that bears a nucleus of zinc(II) tetrapyrrolic macrocycle substituted at the meso positions by four identical substituents. These are formed by a tetrafluorophenyl group that possesses a triazole unit in the para position. This nitrogenous heterocyclic is connected to a 4,4'-di(N-carbazolyl)triphenylamine group by means of a phenylenevinylene bridge, which allows the conjugation between the nucleus and this external electropolymerizable carbazoyl group. In this structure, dendrimeric arms act as light-harvesting antennas, increasing the absorption of blue light, and as electroactive moieties. The electrochemical oxidation of the carbazole groups contained in the terminal arms of the DP 5 was used to obtain novel, stable, and reproducible fully π-conjugated photoactive polymeric films (FDP 5). First, the spectroscopic characteristics and photodynamic properties of DP 5 were compared with its constitutional components derived of porphyrin P 6 and carbazole D 7 moieties in solution. The fluorescence emissions of the dendrimeric units in DP 5 were more strongly quenched by the tetrapyrrolic macrocycle, indicating photoinduced energy transfer. In addition, FDP 5 film showed the Soret and Q absorption bands and red fluorescence emission of the corresponding zinc(II) porphyrin. Also, FDP 5 film was highly stable to photobleaching, and it was able to produce singlet molecular oxygen in both N,N-dimethylformamide (DMF) and water. Therefore, the porphyrin units embedded in the polymeric matrix of FDP 5 film mainly retain the photochemical properties. Photodynamic inactivation mediated by FDP 5 film was investigated in Staphylococcus aureus and Escherichia coli. When a cell suspension was deposited on the surface, complete eradication of S. aureus and a 99% reduction in E. coli survival were found after 15 and 30 min of irradiation, respectively. Also, FDP 5 film was highly effective to eliminate individual bacteria attached to the surface. In addition, photodynamic inactivation (PDI) sensitized by FDP 5 film produced >99.99% bacterial killing in biofilms formed on the surface after 60 min irradiation. The results indicate that FDP 5 film represents an interesting and versatile photodynamic active material to eradicate bacteria as planktonic cells, individual attached microbes, or biofilms.

Ultrafast trans → cis Photoisomerization Dynamics of Alkyl-Substituted Stilbenes in a Supramolecular Capsule.

Ultrafast spectroscopy reveals the effects of confinement on the excited-state photoisomerization dynamics for a series of alkyl-substituted trans-stilbenes encapsulated in the hydrophobic cavity of an aqueous supramolecular organic host-guest complex. Compared with the solvated compounds, encapsulated trans-stilbenes have broader excited-state absorption spectra, excited-state lifetimes that are 3-4 times longer, and photoisomerization quantum yields that are 1.7-6.5 times lower in the restricted environment. The organic capsule disrupts the equilibrium structure and restricts torsional rotation around the central C═C double bond in the excited state, which is an important motion for the relaxation of trans-stilbene from S1 to S0. The location and identity of alkyl substituents play a significant role in determining the excited-state dynamics and photoisomerization quantum yields by tuning the relative crowding inside the capsule. The results are discussed in terms of distortions of the ground- and excited-state potential energy surfaces, including the topology of the S1-S0 conical intersection.

Evidence for Reagent-Induced Spin-State Switching in Tripodal Fe(II) Iminopyridine Complexes.

We present evidence of a spin-state change that accompanies desilylation reactions performed on two related Fe(II) iminopyridine coordination complexes. To probe these systems, we performed titrations with CsF in solution and analyzed the speciation with in situ magnetometry, electrochemistry, and mass spectrometry techniques. We find that pendant tert-butyldimethylsilyl groups are readily cleaved under these conditions, and the resulting desilylated complexes exhibit overall decreased solution magnetic susceptibility values. Density functional theory and ab initio computations probe the impact of substituent identity (prior to- and post-desilylation) on the metal-ligand σ-donor and π-acceptor bonding properties. We attribute the observed spin-state changes to the decrease in entropy associated with the conformational freedom of the silylated high-spin complex, resulting in a more favored low-spin state upon desilylation.

Self-Assembly and Sensing Properties of Rim-Functionalized Oxoporphyrinogens

Simple oxoporphyrinogen derivatives have been shown to be excellent colorimetric sensors for a variety of analytes as well as being effective electron deficient components of photosynthetic model compounds. More recently, this family of compounds has grown to include rim-functionalized compounds, which also exhibit colorimetric properties. In this work, we have prepared a series of differently rim-functionalized oxoporphyrinogens and we will present their properties with respect to sensing, including selective anion binding and chirality sensing, and the photolytic properties of appropriately functionalized compounds. In particular, we demonstrate the importance of substituent identity on the selective anion binding and asymmetric interactions. Observations of the properties of the compounds under irradiation again reveal the importance of molecular structure and cofactor interactions for the photophysical properties of the compounds.