| 1. |
- He, Yixing, et al.
(författare)
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Chain Length Modulated Dimerization and Cyclization of Terminal Thienyl-Blocked Oligopyrranes
- 2022
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Ingår i: Organic Letters. - : AMER CHEMICAL SOC. - 1523-7060 .- 1523-7052. ; 24:29, s. 5428-5432
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Tidskriftsartikel (refereegranskat)abstract
- Oxidation of thienyl-blocked bilane and pentapyrrane afforded chain length dependent products of the symmetric dimer D1 and the thienyloligopyrrin-appended pentaphyrin analogue P2, respectively, with the latter formed by simultaneous dimerization and cyclization. Coordination of D1 and P2 with Cu(II) afforded di-and monometallic complexes D1-Cu2 and P2 -Cu, respectively. These compounds exhibit distinct NIR absorption, with the absorption tail of D1-Cu2 extended to ca. 1900 nm despite its smaller conjugation framework than that of P2 -Cu.
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| 2. |
- Luo, Jiaxin, et al.
(författare)
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Solar cells sensitized by donor-linked concerted companion dyes
- 2023
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Ingår i: Journal of Materials Chemistry C. - : ROYAL SOC CHEMISTRY. - 2050-7526 .- 2050-7534. ; 11:16, s. 5450-5460
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Tidskriftsartikel (refereegranskat)abstract
- Recently, concerted companion (CC) dyes have been developed by covalently linking the acceptors of organic and porphyrin dye units. Herein, a new class of CC dyes XW85 and XW86 have been designed by linking the donors of porphyrin and organic dye units with C6H12 and C12H24 chains, respectively. The DSSCs of XW85 based on the I-3(-)/I- electrolyte show significant J(SC) (17.20 mA cm(-2)) and PCE (8.96%), and XW86 exhibits higher J(SC) (18.55 mA cm(-2)) and PCE (9.76%), which are also higher than those of the corresponding cosensitization systems. However, the PCEs for XW85 and XW86 are lower than that of the acceptor-linked reference dye XW76 despite the obviously larger dye adsorption amounts. Desorption studies reveal that the CC dyes may be either double-anchored or single-anchored, with the double/single anchoring ratios lying in a sequence of XW85 (1.31) < XW86 (1.88) < XW76 (6.34), consistent with that of increasing PCE. These observations indicate that the non-adsorbed sub-dye unit cannot effectively contribute to electron injection, and thus relatively large mono-anchoring proportions for XW85 and XW86 result in their relatively low J(SC), and the difference between XW85 and XW86 indicates that a longer linking chain is beneficial for partially alleviating the unfavorable single anchoring, resulting in superior performance. The results indicate that the photovoltaic behavior for the CC dyes may be further enhanced by avoiding the unfavorable alignment of the two carboxyl groups in opposite directions and thus simultaneously anchoring the two carboxyl groups, which may be realized through more rational molecular design.
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| 3. |
- Fu, Xianbiao, et al.
(författare)
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High-Entropy Alloy Nanosheets for Fine-Tuning Hydrogen Evolution
- 2022
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Ingår i: ACS Catalysis. - : American Chemical Society (ACS). - 2155-5435. ; 12:19, s. 11955-11959
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Tidskriftsartikel (refereegranskat)abstract
- The electrolysis of water is promising for hydrogen production. The development of high-performance and low-cost hydrogen evolution reaction (HER) electrocatalysts is particularly important for the wide application of water electrolyzers. Tuning the hydrogen binding energy (HBE) of materials is an effective way to optimize the HER electrocatalysts, particularly for applications in an acidic environment. Here, we report the discovery of a Pt-free combination, PdMoGaInNi, which has the HBE optimum, via computer-facilitated screening. As the exploratory example of the two-dimensional high-entropy alloy (HEA) for HER, the PdMoGaInNi HEA nanosheets were synthesized to realize the predicted Pt-free combination with optimal HBE. The PdMoGaInNi HEA nanosheets exhibit a high HER activity with low overpotentials of 13 mV at 10 mA cm-2, outperforming commercial Pd/C and Pt/C catalysts. Given the high entropy, lattice distortion, and sluggish diffusion effects of HEA, the PdMoGaInNi shows great long-term durability for at least 200 h in a proton exchange membrane water electrolyzer.
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| 4. |
- Huang, Yanping, et al.
(författare)
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Syntheses and characterization of dithienyl-blocked hexapyrrin and its mononuclear complexes
- 2023
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Ingår i: Journal of Porphyrins and Phthalocyanines. - : World Scientific. - 1088-4246 .- 1099-1409. ; 27:07N10, s. 1089-1096
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Tidskriftsartikel (refereegranskat)abstract
- With the purpose to develop long chain-conjugated oligopyrrin-like compounds and their metal complexes, and thus achieve tunable near-infrared absorption, a dithienyl-blocked hexapyrrane S-2-P-6 was synthesized by acid-catalyzed [2+4+2] condensation, followed by oxidation with DDQ to afford dithiaoctapyrrin 1, and its mononuclear metal complexes 1-Cu and 1-Zn were synthesized by treating 1 with Cu(II) and Zn(II) acetates. All the compounds were systematically characterized by NMR/EPR, and HRMS. The crystal structures revealed that 1 adopts a double hook-like conformation. Whereas, both complexes 1-Cu and 1-Zn adopt spiral-hook hybrid conformations, showing smaller interplanar angles between the rings within the spiral part, compared with those in the hook-like counterpart of molecule 1, which is favorable for red-shifting the absorption. As expected, the absorption band edges for complexes 1-Cu and 1-Zn are red-shifted to ca. 1560 nm, compared with that of 1260 nm observed for 1.
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| 5. |
- Huang, Yanping, et al.
(författare)
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Syntheses and coordination of linear and macrocyclic pentapyrroles possessing a fused moiety : Confusion modulated structural diversity
- 2024
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Ingår i: Dyes and pigments. - : Elsevier. - 0143-7208 .- 1873-3743. ; 223
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Tidskriftsartikel (refereegranskat)abstract
- Porphyrinoids have attracted wide interest because of their vital roles in biological processes and fascinating structural and functional characters. In this work, a doubly N-confused pentapyrrane precursor N2C–P5 has been synthesized with terminal pyrrole ring A and middle pyrrole C incorporated in the N-confused mode. On this basis, pentapyrrin 1 and sapphyrin 2 have been synthesized by oxidizing N2C–P5 with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). Both 1 and 2 possess a [5.5.5]-tricyclic fused ring involving pyrrole B and the neighboring confused pyrrole C. Meanwhile, the formation of 2 involves ring closure between the terminal rings A and E. Notably, 2 exists as a diradical showing a half-field signal in the electron paramagnetic resonance (EPR) spectrum and a singlet ground state with a negative singlet-triplet energy gap of −0.50 kcal/mol. Excellent thermal stability has been observed for 2, which may be related to its large π-conjugated framework involving the fused structure. On this basis, 1 and 2 were treated with Cu(acac)2 to afford Cu(II) complexes 3 and 4, respectively. As a result, an acetylacetonyl moiety is attached at the terminal pyrrole ring E to afford an NNNO coordination environment for complex 3, and the sapphyrin macrocycle of 2 has been cleaved between rings A and B to afford a fused pentapyrrin ligand, furnishing an NNNN coordination environment for complex 4, in which a pentafluorophenyl-ketal group generated during the ring cleavage reaction is attached to ring A, and it can be hydrolyzed to the corresponding pentafluorobenzoyl substituent to afford complex 5. Compared with free bases 1 and 2, complexes 3−5 show more intense low-energy near-infrared (NIR) absorption bands at ca. 791, 926 and 907 nm, respectively. This work provides an effective approach for the syntheses of linear and macrocyclic oligopyrroles with intriguing structures and properties by oxidizing oligopyrranes with precisely designed numbers and positions of N-confused pyrroles.
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| 6. |
- Li, Chengjie, et al.
(författare)
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Tripyrrin-armed isosmaragdyrins : synthesis, heterodinuclear coordination, and protonation-triggered helical inversion
- 2020
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Ingår i: Chemical Science. - : ROYAL SOC CHEMISTRY. - 2041-6520 .- 2041-6539. ; 11:10, s. 2790-2795
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Tidskriftsartikel (refereegranskat)abstract
- Oxidative ring closure of linear oligopyrroles is one of the synthetic approaches to novel porphyrinoids with dinuclear coordination sites and helical chirality. The spatial arrangement of the pyrrolic groups of octapyrrole (P8) affected the position of the intramolecular oxidative coupling of the pyrrolic units; tripyrrin-armed isosmaragdyrin analogue (1) containing a beta,beta-linked bipyrrole moiety was synthesized regioselectively in a high yield by using FeCl3. Ni-II-coordination at the armed tripyrrin site of 1 allowed the formation of diastereomeric helical twisted complexes (2A and 2B) and succeeding Cu-II-coordination at the macrocyclic core afforded heterodinuclear Ni-II/Cu-II-complexes (3A and 3B). Each of them comprised a pair of separable enantiomers, exhibiting P- and M-helices, respectively. Notably, diastereomeric interconversion from 2A to 2B was quantitatively achieved as a consequence of helical transformation under acidic conditions.
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| 7. |
- Li, Qizhao, et al.
(författare)
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Antiaromatic Sapphyrin Isomer : Transformation into Contracted Porphyrinoids with Variable Aromaticity
- 2023
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Ingår i: Angewandte Chemie International Edition. - : Wiley-VCH Verlagsgesellschaft. - 1433-7851 .- 1521-3773. ; 62:1
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Tidskriftsartikel (refereegranskat)abstract
- Sapphyrin is a pentapyrrolic expanded porphyrin with a 22π aromatic character. Herein, we report the synthesis of a 20π antiaromatic sapphyrin isomer 1 by oxidative cyclization of a pentapyrrane precursor P5 with a terminal β-linked pyrrole. The resulting isomer 1, containing a mis-linked bipyrrole unit in the skeleton, exhibits a reactivity for further oxidation due to the distinct antiaromatic electronic structure, affording a fused macrocycle 2, possessing a spiro-carbon-containing [5.6.5.6]-tetracyclic structure. Subsequent treatment with an acid afforded a weakly aromatic pyrrolone-appended N-confused corrole 3, and thermal fusion gave a [5.6.5.7]-tetracyclic-ring-embedded 14π aromatic triphyrin(2.1.1) analog 4. The cyclization at the mis-linked pyrrole moiety of P5 played a crucial role in synthesizing the antiaromatic porphyrinoid susceptible to facile transformation to novel porphyrinoids with variable aromaticity.
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| 8. |
- Li, Qizhao, et al.
(författare)
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Conformation Governed Reactivity of Fused Thia-Sapphyrin Dimers Bearing Multiply Fused Heteroaromatic Rings
- 2023
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Ingår i: CCS CHEMISTRY. - : Chinese Chemical Society. - 2096-5745. ; 5:6, s. 1332-1342
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Tidskriftsartikel (refereegranskat)abstract
- Suitable conformations and proper alignment of complex natural macrocycles are essential for achieving their unique properties. However, such artificial macrocycle prototypes are still limited due to synthetic difficulties. In this respect, directly linked porphyrin analog dimers display tunable conformations and intriguing properties, and thus, they may be employed as a class of promising platforms. Herein, we report that one-pot oxidative dimerization of thiahydrosapphyrin 1 yields dimers, 2(ant)i and 2(syn), comprising a transoid-oriented plate-like bipyrrolo[1,2-a] indolylidene. The thiophene-containing tetrapyrrole arching subunits in 2 lie at the opposite (anti) and same (syn) sides of the plate, respectively. Meanwhile, multiply fused cisoid-orientated dimer 3 was also obtained; a polycyclic pyrrolo-bridged bipyrroloindole derivative tethered with fully pi-conjugated bridges was formed. Notably, the anti-dimer 2(anti) underwent subsequent oxidative fusion to furnish a further-fused [6.5.5.7.5.5.5.6]-octacyclic compound 4(anti). In contrast, the syn-orientated 2(syn) could not be further fused due to the long distance between the potential reaction sites. This study provides a unique approach to the fused dimeric porphyrin analogs for potential near-infrared optical materials by a simple oxidation reaction. It also reveals the importance of conformation-modulated reactivity for constructing complex porphyrin arrays.
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| 9. |
- Li, Qizhao, et al.
(författare)
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Twisted-Planar-Twisted expanded porphyrinoid dimer as a rudimentary reaction-based methanol indicator
- 2020
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Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- Directly linked porphyrin dimers have attracted considerable attention because of their intriguing electronic features. Most emphasis has been placed on either dimers with large dihedral angles between the constituent planar monomeric subunits or those with overall planarity, referred to as "Planar-Twisted-Planar" and "Planar-Planar-Planar", respectively. Herein, we report a "Twisted-Planar-Twisted" framework, the hexaphyrin dimer D that exists in a trans configuration. Treatment of D with MeOH affords two isomeric dimers, MD1 and MD2, both of which incorporate a methoxy moiety and exist in cis orientations with respect to the tethering linkage. The methanol-promoted conversion is accompanied by a readily discernible color change from green to brown and is not induced to an appreciable level by other alcohols. Dimer D thus acts as a rudimentary, albeit highly selective, reaction-based methanol indicator. This work provides a promising approach for constructing reaction-based chemosensors using porphyrinoid dimers of nonplanar subunits with biased reactivity. Directly linked porphyrin dimers show intriguing electronic features but emphasis has been placed on planar monomeric units. Here, the authors report a Twisted-Planar-Twisted framework which can undergo a cis-trans transformation accompanied by a colour change in presence of methanol, making this framework applicable as a methanol sensor.
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| 10. |
- Lu, P. F., et al.
(författare)
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A theoretical investigation on thermoelectric performance of ternary (Bi1-xSbx)(2)Te-3 compound
- 2013
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Ingår i: Journal of Materials Science. - : Springer Science and Business Media LLC. - 0022-2461 .- 1573-4803. ; 48:14, s. 4999-5004
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Tidskriftsartikel (refereegranskat)abstract
- The electronic structure and thermoelectric properties of (Bi1-x Sb (x) )(2)Te-3 compound are investigated by using full-potential linearized augmented plane-wave method and semiclassical Boltzmann theory. The density of states and band structure are studied in detail. The transport coefficients are then calculated with the assumption of the constant relaxation time approximation. We investigated the thermoelectric properties at full range of Sb compositions from x = 0 to x = 1. By using the calculated thermoelectric properties and an averaged thermal conductivity, the figure of merit ZT is obtained. The theoretical investigations show a good agreement with the present experimental data.
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| 11. |
- Lu, P. F., et al.
(författare)
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Investigation on structural, electronic and magnetic propeties of Mn doped Ga12N12 clusters
- 2013
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Ingår i: Journal of Materials Science. - : Springer Science and Business Media LLC. - 0022-2461 .- 1573-4803. ; 48:24, s. 8552-8558
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Tidskriftsartikel (refereegranskat)abstract
- The structural, electronic, and magnetic properties of Ga12N12 cluster doped with monodoped and bidoped Mn atoms have been investigated based on the density functional theory. Substitutional, exohedral, and endohedral configurations are considered. The substitutional doping is found to be most favorable for monodoped clusters, while the bidoped clusters prefer the exohedral isomers. For all the isomer, the magnetic moment is mainly derived from 3d orbitals of Mn atom. The exohedral and endohedral bidoped Ga12N12 clusters all favor antiferromagnetic state.
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| 12. |
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| 13. |
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| 14. |
- Sun, Meng, et al.
(författare)
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Mono- and bis-Pd(II) complexes of N-confused dithiahexaphyrin(1.1.1.1.1.0) with the absorption and aromaticity modulated by Pd(II) coordination, macrocycle contraction and ancillary ligands
- 2024
-
Ingår i: Chemical Science. - : ROYAL SOC CHEMISTRY. - 2041-6520 .- 2041-6539.
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Tidskriftsartikel (refereegranskat)abstract
- To further enrich the coordination chemistry of hexaphyrins and probe the underlying property-structural correlations, N-confused dithiahexaphyrin(1.1.1.1.1.0) (1) with 26 pi-electron H & uuml;ckel aromaticity was synthesized. Based on its unprecedented two unsymmetrical cavities, five palladium complexes 2, 3, 4-Ph, 4-Cl and 5 have been successfully synthesized under various coordinations. Thus, two mono-Pd(II) complexes 2 and 3 with the Pd(II) atom coordinated in the two different cavities were obtained by treating 1 with palladium reagents PdCl2, and (PPh3)(2)PdCl2 respectively. On this basis, bis-Pd(II) complexes 4-Ph and 4-Cl were synthesized by treating 2 and 3 with (PPh3)(2)PdCl2 and PdCl2, respectively. As a result, both 4-Ph and 4-Cl contain two Pd(II) atoms coordinated within the two cavities, with one of the Pd(II) atoms further coordinated to a triphenylphosphine ligand in addition to an anionic ancillary ligand of Ph- and Cl-, respectively. Notably, a further contracted mono-Pd(II) complex 5 was synthesized by treating 1 with Pd(PPh3)(4) by eliminating one of the meso-carbon atoms together with the corresponding C6F5 moiety. These complexes present tunable 26 pi aromaticity and NIR absorption up to 1060 nm. This work provides an effective approach for developing distinctive porphyrinoid Pd(II) complexes from a single porphyrinoid, without resorting to tedious syntheses of a series of porphyrinoid ligands.
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| 15. |
- Xu, Yue, et al.
(författare)
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Confusion Approach Modulated Syntheses of Corrorin Parasitized Hexaphyrins(1.1.1.1.1.0) and the Oxidative Ring Cleavage Behavior
- 2021
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Ingår i: Organic Letters. - : AMER CHEMICAL SOC. - 1523-7060 .- 1523-7052. ; 23:21, s. 8307-8311
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Tidskriftsartikel (refereegranskat)abstract
- A corrorin parasitized hexaphyrin(1.1.1.1.1.0) 1 was synthesized by [4 + 4] condensation, and subsequent treatment with PbO2 afforded hexaphyrin 2 appended with a dipyrrinone moiety via regioselective opening of the corrorin ring. In contrast, oxidation of the corresponding corrorin-N-confused hexaphyrin(1.1.1.1.1.0) hybrid 3 afforded only a keto adduct 4. As a result, the planarity and aromaticity of the hexaphyrin moiety can be modulated.
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| 16. |
- Xu, Yue, et al.
(författare)
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Pyrrolylmethylene Appended Corrorin: Peripheral Coordination and Transformation to Pyridyl Incorporated Hemiporphycene Analogue
- 2023
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Ingår i: Organic Letters. - : AMER CHEMICAL SOC. - 1523-7060 .- 1523-7052. ; 25:10, s. 1793-1798
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Tidskriftsartikel (refereegranskat)abstract
- A pyrrolylmethylene appended corrorin 1 was synthesized and coordinated with [Rh(CO)2Cl]2 to afford 1-Rh with unique RhI-eta 2-CC bonding in addition to the coordination of the dipyrrin-like unit and a carbonyl ligand. Further oxidation of 1 afforded 2, exhibiting a hydrocorrorinone core, and it can be further transformed into pyrrolo[3,2c]pyridine incorporated hemiporphycene analogue 3 upon treatment with HOAc. The side chain modifies the reactivity of corrorin and effectively tunes the NIR absorption of the resulting porphyrinoids.
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| 17. |
- Xu, Yue, et al.
(författare)
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Syntheses of Thiophene-Thiophene-Linked Corrorin Dimers with Tunable Near-Infrared Absorption and Distinctive Reactivity
- 2024
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Ingår i: Organic Letters. - : AMER CHEMICAL SOC. - 1523-7060 .- 1523-7052. ; 26:2, s. 571-576
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Tidskriftsartikel (refereegranskat)abstract
- Thiahexaphyrinone 1 and thia-dipyrrin-appended corrorin 2 have been synthesized. Surprisingly, further oxidation of compound 2 with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in dichloromethane afforded dimer 3 with two molecules of compound 2 linked at the alpha-carbon atoms of the thienyl units. Treatment of compound 3 with DDQ in MeOH and SnCl2 in tetrahydrofuran/H2O afforded the dimethoxy-attached dimer 4 and hydrogenated dihydroxy-attached dimer 5, respectively. These results provide the first examples for synthesizing thiophene-linked porphyrinoid dimers with tunable near-infrared absorption and chirality.
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| 18. |
- Yang, Zhen, et al.
(författare)
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Synthesis and coordination of a dipyrrin appended N-confused porphyrin
- 2023
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Ingår i: Journal of Porphyrins and Phthalocyanines. - : World Scientific. - 1088-4246 .- 1099-1409. ; 27:1, s. 285-292
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Tidskriftsartikel (refereegranskat)abstract
- A hexapyrrane P6 with a terminal N-confused pyrrole was synthesized by acid-catalyzed [3+3] condensation followed by oxidation with DDQ, which did not afford the expected N-confused hexaphyrin. In stead, a rearranged product, i.e., α-dipyrrin appended N-confused porphyrin 1 was obtained in a yield of 46%. Chelation of 1 with Pt(II) afforded the peripheral complex 1-Pt, which was further coordinated with Rh(I) in the cavity to afford the corresponding bimetallic complex 1-Pt-Rh. Both 1-Pt and 1-Pt-Rh exhibit split Soret-like bands and noticeable Q-like bands tailing to the NIR region up to ca. 1200 nm. Single crystal X-ray diffraction analyses of 1 and 1-Pt revealed that the peripheral coordination of Pt(II) slightly modifies the interplanar angle between the porphyrin macrocycle and the dipyrrin unit, which may modulate the absorption spectra. The results of this work compose an interesting example of synthesizing porphyrinoids appended with conjugated peripheral chains by the oxidative ring closure reaction of an oligopyrrane containing a terminal N-confused pyrrole, and such compounds may be used for both inner and peripheral coordination to afford complexes with tunable NIR absorption.
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| 19. |
- Zhao, L., et al.
(författare)
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Electronic structure and thermoelectric properties of Bi-2(Te1-xSex)(3) compound
- 2013
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Ingår i: Solid State Communications. - : Elsevier BV. - 0038-1098. ; 155:Feb., s. 34-39
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Tidskriftsartikel (refereegranskat)abstract
- A first-principles study has been performed to evaluate the electronic structure and thermoelectric properties of Bi-2(Te1-xSex)(3) compound. The transport coefficients are then calculated within the semiclassical Boltzmann theory, and further evaluated as a function of chemical potential assuming a constant relaxation time and an averaged thermal conductivity. Our theoretical calculations show that the ZT value is 1.43 for Bi-2(Te1-xSex)(3) system, and it agrees well with previous experimental data.
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