bluuebunny/crossref_metadata_2025_split huggingface dataset:
(Invited) Functionalized Pi-Extended porphyrins As Sensitizer for Dye-Sensitized Solar Cells
Authors: Wang Hong , Kerr Lei , Jinadasa R. G. Waruna , Li Bihong , Schmitz Benjamin , Matus Alex , Hu Yi 
Published: February 2020

Significant progress has been made on dye-sensitized solar cells sensitized by push-pull porphyrins in recent years.1-3 Through installing push-pull groups at porphyrin meso-positions, exceptionally high power conversion efficiencies have been achieved.4, 5 In this work, we present the recent progress on synthesis and characterization of new classes of functionalized pi-extended porphyrins, and their application as sensitized for dye-sensitized solar cells. We show that through installing push-pull groups at the porphyrin beta-positions, both the UV-Vis absorption bands and fluorescence emission bands are much red-shifted and broadened relative to those of the porphyrins bearing no push-pull groups. These porphyrins show moderate to high power conversion efficiencies. In addition, anchoring group effects will also be discussed in this presentation. The design and synthesis of these organic materials take advantage of the chemistry of bromoporphyrins6-9 and a palladium (0) catalyzed cascade reaction developed in the Wang group.10
The electronic and optical properties of these p-extended porphyrins were measured using UV-Vis spectroscopy, life-time and steady state fluorescence spectroscopy, and cyclic voltammetry. DFT calculations were also performed for these porphyrins.

Reference

1. T. Higashino and H. Imahori, Dalton Trans., 2015, 44, 448-463.
2. M. Urbani, M. Gratzel, M. K. Nazeeruddin and T. Torres, Chem. Rev., 2014, 114, 12330-12396.
3. L. L. Li and E. W. Diau, Chem. Soc. Rev., 2013, 42, 291-304.
4. A. Yella, H.-W. Lee, H. N. Tsao, C. Yi, A. K. Chandiran, M. K. Nazeeruddin, E. W.-G. Diau, C.-Y. Yeh, S. M. Zakeeruddin and M. Grätzel, Science, 2011, 334, 629-634.
5. S. Mathew, A. Yella, P. Gao, R. Humphry-Baker, B. F. Curchod, N. Ashari-Astani, I. Tavernelli, U. Rothlisberger, M. K. Nazeeruddin and M. Gratzel, Nat. Chem., 2014, 6, 242-247.
6. L. Jaquinod, R. G. Khoury, K. M. Shea and K. M. Smith, Tetrahedron, 1999, 55, 13151–13158.
7. L. Jaquinod, R. G. Khoury, K. M. Shea and K. M. Smith, Tetrahedron, 1999, 55, 13151-13158.
8. O. Siri and K. M. Smith, Tetrahedron Lett., 2003, 44, 6103-6105.
9. M. J. Crossley, P. L. Burn, S. S. Chew, F. B. Cuttance and I. A. Newsom, J. Chem. Soc., Chem. Commun, 1991, 1564-1566.
10. R. Deshpande, L. Jiang, G. Schmidt, J. Rakovan, X. Wang, K. Wheeler and H. Wang, Org. Lett., 2009, 11, 4251-4253.

Figure 1
(Invited) The Reactivity and Mechanistic Studies of Group 14 Corrole Complexes
Authors: Fu Xuefeng 
Published: February 2020

The discoveries of facile syntheses of meso-aryl substituted corroles in 1999 triggered the revival of the chemistry of corroles. A variety of main group and transition metal elements were inserted into the corrole ring and some of the complexes show similar or superior properties to the related porphyrin complexes. The corrole germanium hydride showed unusual high reactivity with aldehydes, olefins and alkyl halides to form corrole germanium α-hydroxy alkyl and alkyl complexes. More importantly, the efficient photo-activation of N-H bond by TEMPO-Ge corrole complexes was observed and the mechanism was investigated based on EPR analysis. The reactivity of Sn corrole was also studied. Activation of N–H bonds with silicon and its low-valent heavier congeners typically proceeds via 2 electron pathways: i) a direct oxidative addition of the N–H bond to the low-valent metal center or ii) a metal-ligand cooperative process. Light-promoted N–H bond activation by main group element radicals has thus far rarely been encountered, but provides an attractive strategy to activate amines with lower activation energies. We observed the light-driven activation of N–H bonds by an organo-germanium corrole complex [(TPFC)Ge(TEMPO)] (TPFC = tris(pentafluorophenyl)corrole, TEMPO = (2,2,6,6-tetramethylpiperidin-1-yl)oxyl) involving a radical pathway to form germanium amides in high yields at room temperature.
(Invited) [30]Trithiadodecaazahexaphyrins: Synthesis and Properties
Authors: Trukhina Olga , Islyaikin Mikhail , Rodriguez-Morgade M. Salome , Torres Tomas , Ivanov Eugeni , Caballero Esmeralda 
Published: February 2020

[30]Trithiadodecaazahexaphyrins are 30 π-electron planar analogues of hexaphyrins that have received a special attention in a relation to their non-aromatic nature. Exceptional chemical versatility and architectural flexibility of these macrocycles allow modification of their peryphery as well as an insertion of up to three transition metals within their central cavity and – as a result – the fine-tuning of their physical and chemical properties. Owing to their intense absorption in the visible region of the solar spectrum, complementary to that of porphyrins and phthalocyanines, high extinction coefficients, and high optical and thermal stabilities , thiadiazoloporphyrinoids evolve as promising light-harvesting building blocks, complementary to tetrapyrrolic macrocycles and carbon nanostructures such as fullerenes, carbon nanotubes and graphene. In this communication a brief summary of our recent work in this area is given.
(Invited) Predicting the Degree of Aromaticity of Novel Porphyrinoid Compounds
Authors: Fliegl Heike 
Published: February 2020

Electronic and spectroscopic properties of porphyrinoid macrocycles are, to a large extent, determined by the number of π-electrons participating in the conjugation network. Full control of the number of π-electrons implies full control of the aromatic or antiaromatic character of the molecule. To achieve this, knowledge about the electron delocalization pathways within a molecule is essential. Experimentally, these pathways are not easily accessible. Therefore theoretical studies are necessary to complement experiments that aim at systematically synthesizing porphyrinoids with distinct properties.
A computational approach to achieve this is the gauge including magnetically induced current density method (GIMIC). GIMIC is a independent program that is used for the calculation of magnetically induced current densities using London orbitals.[1, 2] Numerical integration of the current flow around molecular rings and along selected chemical bonds can be used for determining current pathways and the degree of aromaticity of various molecules according to the magnetic criterion.[3,4] In my talk I am going to present the GIMIC method and briefly discuss the idea behind it. I will illustrate what type of information is accessible through current density studies. Some very recent results on carbaporphyrinoids will be highlighted showing the potential and the challenges of the method.[5,6]

References:

[1] J. Jusélius, D. Sundholm and J. Gauss, J. Chem. Phys., 121, 3952-3963 (2004).
[2] H. Fliegl, S. Taubert, O. Lehtonen and D. Sundholm, Phys. Chem. Chem. Phys., 13, 20500- 20518 (2011).
[3] R. Valiev, H. Fliegl and D. Sundholm, Phys. Chem. Chem. Phys., 16, 11010-11016 (2014).
[4] H. Fliegl, F. Pichierri and D. Sundholm, J. Phys. Chem. A, 119, 2344-2350 (2015).
[5] R. Valiev, H. Fliegl and D. Sundholm, J. Phys. Chem. A, 119, 1201-1207 (2015).
[6] R. Valiev, H. Fliegl and D. Sundholm, Phys. Chem. Chem. Phys., 17, 14215-14222 (2015).
(Invited) Interactions of Antioxidant-Substituted Macrocycles
Authors: Hill Jonathan P. , Payne Daniel , Matsushita Yoshitaka , Jin Shangbin , Labuta Jan , Ariga Katsuhiko 
Published: February 2020

Porphyrins substituted with antioxidant 2,6-di-tert-butylphenol substituents have been shown to exhibit different conformations based on the oxidation state of those substituents leading to the oxoporphyrinogens.1,2 We have attempted to apply this feature in numerous other macrocyclic and non-macrocyclic chromophores in order to assess any possibility for controlling molecular morphology. These attempts have included phthalocyanines, triarylamines (TPA), hexaphenylbenzene (HPB) and resorcinarene. Here, we will describe the results of these investigations including highlighting the potential applications of different compounds obtained from the porphyrin system,3,4 synthesis and structure in the phthalocyanine,5 TPA and HPB systems,6 and an extensive crystallographic analysis of the resorcinarene system.7 We will also present spectroscopic aspects of these compounds including how they interact with some analytes, and electrochemical data illustrating coupling between structures and the oxidation states of the compounds.
References: (1) F. D’Souza, N. K. Subbaiyan, Y. Xie, J. P. Hill, K. Ariga, K. Ohkubo, S. Fukuzumi, J. Am. Chem. Soc. (2009) 131, 16138–16146. (2) J. P. Hill, I. J. Hewitt, C. E. Anson, A. K. Powell, A. L. McCarthy, P. Karr, M. Zandler, F. D’Souza, J. Org. Chem. (2004) 69, 5861–5869. (3) S. Ishihara, J. Labuta, T. Šikorský, J. V. Burda, N. Okamoto, H. Abe, K. Ariga, J. P. Hill, Chem. Commun. (2012) 48, 3933–3935 (4) A. Shundo, J. Labuta, J. P. Hill, S. Ishihara, K. Ariga, J. Am. Chem. Soc. (2009) 131, 9494–9495; J. Labuta, S. Ishihara, A. Shundo, S. Arai, S. Takeoka, K. Ariga, J. P. Hill, Chem. Eur. J. (2011) 17, 3558–3561. (5) J. P. Hill, N. K. Subbaiyan, F. D’Souza, Y. Xie,

S. Sahu, N. M. Sanchez-Ballester, K. Ariga, Chem. Commun. (2012) 48, 3951–3953. (6) S. Jin, J. P. Hill, F. D'Souza, K. Ariga, (2016) in press. (7) D. Payne, J. P. Hill, F. D'Souza, K. Ariga, (2016) in press.
Figure. X-ray crystal structure of antioxidant-substituted resorcinarene.

Figure 1
(Invited) 'totem' C2-Symmetrical Iron(III) Porphyrin Complexes to Stereoselectively Promote the Alkene Cyclopropanation
Authors: Gallo Emma , Intrieri Daniela , Carminati Daniela Maria , Toma Lucio , Le Gac Stéphane , Boitrel Bernard 
Published: February 2020

The stereoselective synthesis of cyclopropanes is an important issue in synthetic chemistry due to the relevance of these three-member carbon rings which often represent the active part in biological and/or pharmaceutical compounds.1,2 The one pot reaction of diazo compounds with alkenes represents a sustainable methodology to achieve cyclopropanes due to the formation of N2 as the only stoichiometric by-product. The reaction is efficiently catalysed by metal porphyrins which promote the synthesis of cyclopropanes with excellent diastereo- and enantioselectivities. Considering the importance in developing eco-friendly catalytic procedures, we are currently studying the catalytic activity of iron porphyrins which display a cheap, efficient and low toxic metal centre.
The two iron complexes 1Fe and 2Fe are good catalysts for the alkene cyclopropanation and both have one C2 axis within the porphyrin plane and exhibit an open space on each side for the substrate access. Complex 1Fe displays a pre-organized structure which was responsible for excellent trans-diastereoselectivities (94-99%) in alkene cyclopropanations while the presence of chiral moieties in 2Fe allowed to perform the reactions with also a very good enantioselectivity (up to 87%).2

Experimental data disclosed that each ‘totem’ portion of 2Fe has a specific catalytic role: i) the porphyrin core containing the active iron centre is in charge to activate the diazo compound; ii) benzylic moieties are responsible for the reaction diasteroselectivity and iii) the two chiral binaphthyl groups allow the enantioselective synthesis of cyclopropanes.
The study of the reaction scope revealed that both 1Fe and 2Fe catalysts were active in promoting the cyclopropanation of several olefins by differently substituted diazo compounds.

References

1. a) C. A. Carson, M. A. Kerr, Chem. Soc. Rev.
2009, 38, 3051-3060. b) A. K. Kumar, Int. J. Pharm. Pharm. Sci. 2013, 5, 467-472.
2. D. Intrieri, S. Le Gac, A. Caselli, E. Rose, B. Boitrel, E. Gallo, Chem. Commun. 2014, 50, 1811-1813.

Figure 1
(Invited) Catalytic Activity of Vitamin B12 under Light Irradiation
Authors: Gryko Dorota 
Published: February 2020

Vitamin B12 is a highly functionalized tetrapyrrolic compound bearing a central cobalt ion. It has been examined as an oral delivery vehicle for therapeutic agents, as an artificial enzyme and more importantly as a catalyst for various organic reactions.[1], [2] Like most great ideas vitamin B12 catalysis was inspired by the ultimate chemist Nature, as methylcobalamin and adenosylcobalamin are involved in numerous biocatalytic reactions including isomerization, methylation and dehalogenation.[2] This type of catalysis has been successfully translated into the laboratory and used in a small collection of reactions.[3] The advantage of using vitamin B12 lays in the complete stability of the central cobalt ion, whereas most catalytic reactions require the addition of toxic metals plus complex ligands into a cocktail of reagents, vitamin B12 in itself is a package deal. Furthermore, it has been well documented that the reaction mechanism usually follows a radical pathway, bringing a new dimension to this already interesting field.
We have shown that vitamin B12 is an effective catalyst for not only C-C bond forming reaction but also cleavage of C-O bonds under light irradiation.
Reference:
1. Banerjee, R. Chemistry and Biochemistry of B12, John Wiley & Sons, Inc, 1999
2. K. ó Proinsias, M. Giedyk, D. Gryko, Chem. Soc. Rev.
2013, 42, 6605-6619.
3. Giedyk, M.; Fedosov, S.; Gryko, D. Chem.
Commun.
2014, 50, 4674-4676.
4. a) Shimakoshi, H.; Nishi, M.; Tanaka, A.; Chikama, K.; Hiseada, Y. Chem. Commun. 2011, 47, 6548-6550. b) K. Tahara, Y. Hisaeda, Green Chem.
2011, 13, 558-561. H. Shimakoshi, L. Li, M. Nishi, Y. Hisaeda, Chem. Commun.
2011, 47, 10921-10923.

Figure 1
(Invited) Functionalizing P-Extended Porphyrins
Authors: Wang Hong , Jinadasa R. G. Waruna , Fang Yuanyuan , Kumar Siddhartha , Kadish Karl M. , Hu Yi 
Published: February 2020

Pi-extended porphyrins possess an unique set of photophysical and optoelectronic properties due to their extended pi structure. Pi-extended porphyrins promise broad application in various areas ranging from biomedicine to organic electronics due to their much broadened and red-shifted UV-Vis absorption and emision bands..1-4 In this presentation, we report methodolgy development for the synthesis and functionalization of several series of pi-extended porphyrins including push-pull dibenzoporphyrins,5, 6 A2B2
push-pull tetrabenzoporphyrins, and porphyrins oligomers linked through porphyrin beta-positions. New push (electron-donating groups) and pull (electron-withdrawing) groups were introduced at the porphyrin beta-positions and push-pull effects were studied. The electronic and optical properties of these p-extended porphyrins were measured using UV-Vis spectroscopy, steady state fluorescence spectroscopy, and cyclic voltammetry. DFT calculations were also performed for these porphyrins.
Reference
1. A. V. Cheprakov and M. A. Filatov, J. Porphyrins Phthalocyanines, 2009, 13, 291-303.
2. C. M. Carvalho, T. J. Brocksom and K. T. de Oliveira, Chem. Soc. Rev., 2013, 42, 3302-3317.
3. N. Ono, H. Yamada and T. Okujima, in The Porphyrin Handbook, eds. K. M. Kadish, K. M. Smith and R. Guilard, World Scientific 5 Toh Tuck Link, Singapore, 2010, vol. 2, ch. 7.
4. T. Tanaka and A. Osuka, Chem. Soc. Rev., 2015, 44, 943-969.
5. R. G. W. Jinadasa, Y. Fang, Y. Deng, R. Deshpande, X. Jiang, K. M. Kadish and H. Wang, RSC Adv., 2015, 51489-51492.
6. R. G. W. Jinadasa, Y. Fang, S. Kumar, A. J. Osinski, X. Jiang, C. J. Ziegler, K. M. Kadish and H. Wang, J. Org. Chem., 2015, ASAP.

Figure 1
(Invited) Synthesis and Characterization of Photoactive Porphyrin Electropolymers
Authors: Otero Luis Alberto 
Published: February 2020

The design and development of new polymeric functional material for application in organic optoelectronic devices, like polymer solar cells, is one of the most active areas of research, mainly due to the continuous search for low cost renewable energy sources. Flexibility, solution processability, and short energy payback time, are among the very important characteristics of the organic based materials that make possible their application in large area devices. However, despite the facts that high power conversion efficiencies have been attained with bulk heterojunction structures, and that the potentiality of the organic photovoltaic technology is still huge, to date industrial production and large scale commercialization have not been achieved, a major issue being the transfer of the efficiencies obtained on small area cells to large area modules. Thus, the development of new polymeric materials and devices construction methods are still necessary, in order to find procedures that allow the implementation of this relevant technology.
One of the principal difficulties that the use of organic polymers in electronics has to face is the ﬁlm deposition methodology over the conducting or semiconducting contacts. The most common approaches rely on thermal evaporation and solution-processing methods. However, thermal evaporation requires materials with adequate sublimation capability and thermal stability, properties that are difficult to reach in polymers. Also, solution processes, such as dip - or spin - coating methodologies, require polymeric materials with intrinsic high solubility. On the contrary, electropolymerization of suitable photoelectroactive monomers allows the synthesis and formation of polymeric ﬁlms in one step, with the possibility to get control over pattern and thickness, two very important aspects in the implantation of industrial processes. In the last years we developed porphyrin polymeric materials, produced by electrochemical methods. These materials exhibited photovoltaic and electrochromic properties. The monomers were planned with the aim to achieve their polymerization through dimerization of the electrochemically generated tryphenyl amine and/or carbazole radical cations, giving rise to tetraphenylbenzidine and/or dicarbazole substructures with hole transport capability. These polymers demonstrate their capacity for the generation of photoinduced charge separated states, with light absorption in a broad region of the visible spectrum, and hold the potentiality for their application in the development of optoelectronic devices.
FRET-Based Ratiometric Detection of Metal Ions
Authors: Bian Yongzhong , Zhu Mengliang , Zhang Dongli , Lu Wenxin , Zhang Jinghui , Jiang Jianzhuang 
Published: February 2020

Fluorescent sensors for detecting transition- and heavy-metal ions in environmental and biological systems have received considerable attention. In comparison with single emission intensity-based “turn-off” or “turn-on” sensors, ratiometric sensors can afford self-calibration by dual-channel detection and thus perform precise analyses against various environmental and instrumental factors. One of the most frequently applied mechanisms for ratiometric sensing is the binding-induced modulating of intramolecular fluorescence resonance energy transfer (FRET), which is highly dependent on the distance between the donor and acceptor, the overlap integral between the donor emission and acceptor absorption, and the relative orientation of the transition dipoles. Hence the binding-induced changes of the spatial and electronic structure can effectively modulate the FRET efficiency within a donor-acceptor system, consequently leading to change in the fluorescence intensity of the donor and acceptor.
In order to develop heavy-metal ion sensors, we have proposed a new strategy for ratiometric fluorescent detection that is based on the rational integration of two sensing mechanisms of a binding-induced modulating of FRET efficiency coupled with a metal-chelating quenching of fluorescence. Synergistic coupling of these two functions leads to exceptionally large change in the emission ratio, thus allowing for ratiometric detecting of metal ions with improved sensitivity. As proof-of-concepts, a BODIPY-porphyrin dyad (1) and a series of phthalocyanine-porphyrin(Zn) hetero-oligomers (2-4) have been designed for ratiometric fluorescent detection, which show excellent selectivity and sensitivity toward Ag+ and Pb2+ respectively.

Figure
1. Ratiometric fluorescent detection of Ag+ by FRET-based BODIPY-porphyrin dyad (1).
References
1. Zhu, M.; Bian Y. et al. Inorg. Chem., 2014, 53, 12186-12190.
2. Zhang, D.; Bian Y. et al. 2015, submitted.

Figure 1
Synthesis of Oxide-Anchored Graphene Sheets By Electrochemical Exfoliation
Authors: Lai Chun-Han , Zhou Xin , Kim Hyung-Seok , Dunn Bruce 
Published: February 2020

Niobium oxide/carbon (Nb2O5/C) composites were synthesized in a one-pot process by combining electrochemical exfoliation of graphite with anodic deposition of niobium oxide. The purpose of this study is to develop an electrolyte system that includes a precursor for oxide deposition as well as graphite exfoliation agents. We anticipated that the oxide coating on graphene morphology would provide excellent ‘wiring’ to the transition metal oxide and enable redox reactions to occur at high rates. For electrochemical exfoliation, sulfuric acid and oxalic acid have been commonly used to efficiently prepare high-quality graphene sheets in a large quantity. In the research reported here, various amounts of ammonium niobate oxalate hydrate (NH4NbO(C2O4)2-nH2O) were dissolved in 1M sulfuric acid and oxalic acid for a systematic study. A control system of 1M hydrochloric acid, a relatively weak exfoliation agent, was also investigated for comparison.
To understand the ion species in the electrolytes, Raman spectroscopy was used to determine the relative amount of the dissolved oxalatooxoniobate. The experimental setup consists of a high-purity graphite rod as the anode and a Pt foil as the cathode. Voltages of 5 to 10V were applied across the electrodes for 30 minutes. After that, the Nb2O5-anchored exfoliated carbons were collected, washed, and characterized by different techniques. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were used to image sample morphologies and perform elemental distribution, respectively. Thermogravimetric analysis (TGA) was used to quantify Nb2O5 and carbon contents and X-ray Diffraction (XRD) was used to identify Nb2O5phases. Raman spectroscopy was also used to determine carbon-carbon bonding quality while transmission electron microscopy (TEM) was used to image the oxide nanoparticle distribution on the carbon nanostructures.
The complex NbO(C2O4)2H2O− in sulfuric acid was successfully converted into Nb2O5 on the exfoliated graphene sheets. In contrast, NbO(C2O4)3
3- in oxalic acid prevented graphite from exfoliating by blocking the pathways for intercalation and active sites for oxide growth. The Nb2O5/C composites obtained using the hydrochloric acid electrolyte exhibits a uniform coating of Nb2O5 on thin graphene layers (Figure 1). Finally, a mechanism for simultaneous deposition/exfoliation was proposed based on interactions between oxalatooxoniobate ions and graphite electrodes. The Nb2O5/C composites were tested for energy storage and exhibited good energy densities at high charge/discharge rates.

Figure 1