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1.
Small ; : e2311671, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38544302

RESUMEN

Energy-efficient white light-emitting diodes (LEDs) are in high demand across the society. Despite the significant advancements in the modern lighting industry based on solid-state electronics and inorganic phosphor, solid-state lighting (SSL) continues to pursue improved efficiency, saturated color performance, and longer lifetime. Here in this article, robust, narrow emission band nanorods (NRs) are disclosed with tailored wavelengths, aiming to enhance the color rendering index (CRI) and luminous efficacy (LE). The fabricated lighting device consists of NRs of configuration CdSe/ZnxCd1-xS/ZnS, which can independently tune CRI R1-R9 values and maximize the luminous efficacy. For general lighting, NRs with quantum yield (QY) up to 96% and 99% are developed, resulting in ultra-efficient LEDs reaching a record high luminous efficacy of 214 lm W-1 (certified by the National Accreditation Service). Furthermore, NRs are deployed onto mid-power (0.3 W@ 50 mA) LEDs, showing significantly enhanced long-term stability (T95 = 400 h @ 50 mA). With these astonishing properties, the proposed NRs can pave the way for efficient lighting with desired optical spectrum.

2.
Chemistry ; 30(6): e202303193, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-37943119

RESUMEN

Cyclic azobenzene-BODIPY hybrids were synthesized via cyclization by 1) acid-catalysed condensation of azobenzene-bridged dipyrroles with 3,5-di-tert-butylbenzaldehyde, 2) oxidation with DDQ, and 3) metalation with BF3 ⋅ Et2 O. The structures of many cyclic hybrids have been confirmed by single crystal X-ray analysis. The absorption spectra of the hybrids reveal the effective cyclic conjugation. The ultrafast measurements reveal that the photoexcited decays of these cyclic hybrids depend upon the ring size and connectivity.

3.
Inorg Chem ; 63(13): 5769-5772, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38291644

RESUMEN

CuII metalations of carbaporphyrins 1-4 gave the corresponding CuII complexes 1-Cu, 2-Cu, 3-Cu, and 4-Cu with varying degrees of distortions in CuII square-planar coordination. Upon treatment with Cu(OAc)2, 1-Cu was inert but 2-Cu and 3-Cu gave the respective O-atom-inserted complexes 2-OCu and 3-OCu. Further, 3-Cu and 4-Cu were converted to meso-methoxynickel(II) porphyrins 3-OMe and 4-OMe, respectively, via treatment with Cu(OAc)2 in methanol. meso-Hydroxynickel(II) porphyrin 3-OH was obtained by the treatment of 3-OCu by acetic acid. The treatment of 4-Cu with Cu(OAc)2 in the presence of acetic acid gave 5,15-diketoporphyrinogen 4-O. CuII complexes of carbaporphyrins became more reactive with an increased distortion in CuII square-planar coordination.

4.
Molecules ; 29(3)2024 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-38338452

RESUMEN

The efficient synthesis of nanosheets containing two metal ions is currently a formidable challenge. Here, we attempted to dope lanthanide-based bimetals into porphyrin-based metal-organic skeleton materials (MOFs) by microwave-assisted heating. The results of the EDX, ICP, and XPS tests show that we have successfully synthesized porphyrin-based lanthanide bimetallic nanosheets (Tb-Eu-TCPP) using a household microwave oven. In addition, it is tested and experimentally evident that these nanosheets have a thinner thickness, a larger BET surface area, and higher photogenerated carrier separation efficiency than bulk porphyrin-based bimetallic materials, thus exhibiting enhanced photocatalytic activity and n-type semiconductor properties. Furthermore, the prepared Tb-Eu-TCPP nanomaterials are more efficient in generating single-linear state oxygen under visible light irradiation compared to pristine monometallic nanosheets due to the generation of bimetallic nodes. The significant increase in catalytic activity is attributed to the improved separation and transfer efficiency of photogenerated carriers. This study not only deepens our understanding of lanthanide bimetallic nanosheet materials but also introduces an innovative approach to improve the photocatalytic performance of MOFs.

5.
Angew Chem Int Ed Engl ; : e202409655, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38967990

RESUMEN

5,18-Dimesitylorangarin and its BF2 complex were synthesized by double SNAr reaction of 3,5-dibromo-BODIPY with a-(pyro-2-ly)dipyrrin as the first examples of meso-aryl-substituted orangarin. These orangarins, delineated as [20]pentaphyrin(1.0.1.0.0), are strongly antiaromatic but rather stable. The free base orangarin was coupled by oxidation with MnO2 to give a 11,11'-linked dimer, a cyclooctatetraene(COT)-centered trimer, and a spiro-trimer. Fused COT-centered 3H-orangarin dimer was oxidized to the corresponding 2H-orangarin dimer, which was further coupled to give a triply COT centered 2H-orangarin tetramer. 3H-Orangarin oligomers are all antiaromatic as evinced by extremely low-field-shifted 1H NMR signals of the inner NH and ill-defined absorption spectra with broad tails. In contrast, COT-centered 2H-orangarin dimer and tetramer show moderately low-field-shifted NH signals and intense NIR absorbance over 900 nm, suggesting the effective p-conjugation through the COT bridge and almost non-antiaromatic character. These orangarin oligomers exhibit many reversible redox potentials owing to the intramolecular electronic interactions. Regardless of the different aromatic characters, all the orangarin monomers and oligomers exhibit very rapid excited-state decays.

6.
Angew Chem Int Ed Engl ; : e202408478, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38829748

RESUMEN

Singly-linked aromatic [22]smaragdyrin BF2 complex dimer was synthesized by the reductive coupling of 16-brominated [22]smaragdyrin BF2 complex, which was oxidized to a stable diradical with PbO2. As the first example of fused smaragdyrin dimer, a fused [22]smaragdyrin BF2 complex dimer was synthesized by the oxidation of a CuCl-BF2 complex dimer with FeCl3 and subsequent reduction with NaBH4. After removal of the BF2 group, the singly-linked and fused aromatic dimers were oxidized to the corresponding antiaromatic [20]smaragdyrin free base dimers. The first oxidation and reduction potentials of these dimers are split depending upon the intramolecular electronic interactions, which are larger for the fused dimers. Despite the large electronic interactions, the aromatic and antiaromatic characters are well preserved in the fused dimers.

7.
Angew Chem Int Ed Engl ; 63(16): e202401233, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38251909

RESUMEN

Norcorrole Ni(II) complexes have recently received considerable attention because they are readily accessible antiaromatic molecules. Their high stability under ambient conditions and ease of synthesis have enabled the exploration of the intrinsic properties of antiaromatic molecules. Here, we report the synthesis and properties of meso-meso singly linked porphyrin-norcorrole hybrids and a triply linked porphyrin-norcorrole hybrid. The singly linked and triply linked porphyrin-norcorrole hybrids were fully characterized, including an X-ray structural analysis. Due to their orthogonal conformation, the singly linked hybrids maintain the individual electronic properties of their porphyrin and norcorrole subunits, while the triply linked hybrid shows a significantly smaller electrochemical HOMO-LUMO gap (0.45 eV) than that of Ni(II) dimesitylnorcorrole (1.08 eV). Furthermore, the triply linked hybrid exhibits singlet diradical characteristics, as confirmed by VT NMR, ESR, and SQUID experiments.

8.
Angew Chem Int Ed Engl ; : e202407340, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38748468

RESUMEN

Exploration of expanded porphyrins with unprecedented reactivities has remained important. Here [22]pentaphyrins(2.0.1.1.0) were synthesized as a constitutional isomer of sapphyrin by acid-catalyzed cyclization of 1,14-dibromo-5,10-diaryltripyrrin with 1,2-di(pyrro-2-ly)ethenes. These pentaphyrins display roughly planar structures and varying aromaticities depending upon the vinylene structures. The 19,20-ditolyl pentaphyrin gave an N-fused product and an unprecedented pyrrole-rearranged product, depending upon the oxidation conditions. Remarkably, upon the metalation with CuCl, the N-fused product and the pyrrole-rearranged product afforded an inner ß-ß coupled face-to-face CuII complex dimer and an outer ß-ß coupled lateral CuII complex dimer, respectively, in fairly good yields. Further, [22]pentaphyrin(2.0.1.1.0) fused with a NiII porphyrin was effectively dimerized upon oxidation with MnO2 to give a 16-16' directly linked dl-dimer.

9.
Angew Chem Int Ed Engl ; 63(8): e202319005, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38117023

RESUMEN

Pyrrole-sharing fused hybrids of NiII porphyrin with PdII N-confused(NC)-corrole and PdII NC-oxaporphyrin were synthesized by post-fabrication of NiII porphyrins. Specifically this consists of Friedel-Crafts type aromatic substitution reaction of meso-free NiII porphyrin with α,α'-dibromotripyrrin and Pd(OAc)2 assisted cyclization, and final heating to induce a Pd-C bond formation. NiII porphyrins fused with PdII NC-corrole and with PdII NC-oxaporphyrins show coplanar structures with a shared pyrrole unit. In these hybrids, the PdII NC-oxaporphyrin is aromatic and the PdII NC-corrole is moderately antiaromatic and these local electronic properties interact to influence the whole network.

10.
J Viral Hepat ; 30(5): 427-436, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36562258

RESUMEN

Although there are therapeutic advantages for hepatitis B virus (HBV) withpegylated interferon alpha (peg-IFNα) treatment compared with nucleos(t)ide analog (NAs) therapy, the effect difference in infected population at different phases has not been well established. We studied the clinical efficacy of peg-IFNα in two populations with HBV infection, including inactive HBsAg carrier (IHC) and chronic hepatitis B (CHB). A total of 328 HBV-infected patients were included in this real-world analysis. Patients were divided into two groups according to the infected stages. Peg-IFNα monotherapy or combination therapy with NAs were used in IHCs, and peg-IFNα added-on NAs therapy was applied to patients with CHB. The primary efficacy endpoint was HBsAg loss at Week 24. Results: The Kaplan-Meier cumulative rates of HBsAg loss were 39.50% (n = 47/119) in IHC group and 28.71% (n = 60/209) in CHB group at Week 24 (p < .05). After Propensity Score Matching (PSM), the HBsAg loss rates were 36.84% (n = 35/95) and 32.63% (n = 31/95), respectively (p > .05). Patients with baseline HBsAg level < 100 IU/ml achieved higher rates of HBsAg clearance in IHC and CHB group (before PSM: 47.44% vs. 42.86%, after PSM: 49.12% vs. 45.83%, all p values > .05). Baseline HBsAg level and its level decline from baseline to Week 12 can be as the predictors for HBsAg loss at Week 24 in both groups. Hence, the efficacy of HBsAg clearance was broadly similar between IHCs and NA-treated CHB patients during the early peg-IFNα therapy. A significant downward trend of HBsAg level was observed in both groups during peg-IFNα therapy.


Asunto(s)
Virus de la Hepatitis B , Hepatitis B Crónica , Humanos , Hepatitis B Crónica/tratamiento farmacológico , Antivirales/uso terapéutico , Antígenos de Superficie de la Hepatitis B , Interferón-alfa/uso terapéutico , Resultado del Tratamiento , Polietilenglicoles/uso terapéutico , Antígenos e de la Hepatitis B , ADN Viral
11.
Chemistry ; 29(62): e202302340, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37580279

RESUMEN

Dithienylethene (DTE)-embedded expanded porphyrins were synthesized and confirmed to be photochemically inactive due to the lowest excited state of the expanded porphyrins. On the other hand, DTE-embedded expanded calixphyrins exhibited reversible photochromism upon UV-irradiation to form colored closed forms, which reverted to colorless open forms upon red-light irradiation. The closed forms were oxidized with DDQ or the air to lock the recorded information by converting to photochemically inactive expanded porphyrins. This was unlocked by reduction with NaBH4 to restore expanded calixphyrins with photochromism activity. These gated photochromic behaviors were demonstrated in PMMA (polymethyl methacrylate) film.

12.
Chemistry ; 29(59): e202301955, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37518990

RESUMEN

Fused-benzoheptagon-installed NiII porphyrins were synthesized by a protocol consisting of (2-formyl)arylation at the meso-position(s) of NiII porphyrins, conversion of formyl group to methoxyethene group by Wittig reaction, and final Bi(OTf)3 -catalyzed cyclization. The structures of these porphyrins have been revealed by X-ray analysis. Owing to the installed heptagon ring(s), these porphyrins show curved structures with conformational flexibility. Dimer has been shown to have a small activation barrier for inversion and to capture C60 and C70 with large association constants with adjustable conformational changes.

13.
Chemistry ; 29(14): e202203517, 2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36479740

RESUMEN

m-Benziporphyrin(1.1.0.0) and m-pyreniporphyrin(1.1.0.0) were prepared as ring-contracted carbaporphyrins. While m-Benziporphyrin(1.1.0.0) was unstable, m-pyreniporphyrin(1.1.0.0) was fairly stable. Both of their PdII complexes showed distorted coordination structures with extremely short Pd-C bonds. As compared with the reported m-benziporphyrin PdII complexes, these PdII complexes showed considerably small HOMO-LUMO gaps, despite their smaller molecular size. PdII metalation of the m-pyreniporphyrin(1.1.0.0) dimer gave the corresponding PdII complex, which showed similar distorted coordination and a smaller HOMO-LUMO gap. Finally, PdII metalation of a pyrene-sharing formal p-benziporphyrin(1.1.1.1) dimer gave a nonaromatic PdII dimer, which rearranged to an aromatic PdII complex upon treatment with alumina.

14.
Chemistry ; 29(11): e202203484, 2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36422469

RESUMEN

meso-Trimesityl-substituted [20]smaragdyrin freebase was synthesized by p-toluenesulfonic acid catalyzed reaction of 5-mesityldipyrromethane and 2,14-dibromodipyrrin in an improved yield of 63 %. Unexpectedly, treatment of the [20]smaragdyrin freebase with BF3 ⋅ OEt2 and triethylamine (TEA) gave a stable radical species, in which the BF2 unit is coordinated at the tripyrrin site, probably by ready release of a hydrogen atom of a [22]smaragdyrin BF2 complex. Similar treatment of [22]smaragdyrin free base produced another [22]smaragdyrin BF2 complex, in which the BF2 unit is coordinated at the dipyrrin site. The tripyrrin site coordinated neutral radical was oxidized with AgSbF6 to give a stable antiaromatic cation; this was reduced with NaBH4 to its 22π congener, which was easily oxidized back to the neutral radical in the air and rearranged to thermodynamically stable dipyrrin site coordinated [22]smaragdyrin BF2 complex upon treatment with BF3 ⋅ OEt2 and TEA. Further, the dipyrrin site coordinated [22]smaragdyrin BF2 complex was similarly oxidized to a stable neutral radical and a stable cation in a stepwise manner. This work demonstrates a rare ability of smaragdyrin BF2 complexes to exist in multiple redox states, particularly forming a stable neutral radical by facile release of a hydrogen atom.

15.
Inorg Chem ; 62(10): 4385-4391, 2023 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-36857465

RESUMEN

In recent years, the synthesis, crystalline structure, and applications of zeolite imidazole frameworks (ZIFs) have attracted extensive attention. Since the ZIF-L phase was synthesized, a new phase was observed during the heating process, but its crystal structure is unknown. The unknown new phase, which was named ZIF-L300 in this study, was confirmed again. In this study, the X-ray powder diffraction technique and Rietveld refinement were used to solve the crystalline structure of the unknown ZIF-L300 phase. The results demonstrate that ZIF-L300 has the same chemical formula (ZnC8N4H10) as in ZIF-8 and belongs to a hexagonal structure with a space group of P61. The lattice parameters have been determined as follows: a = b = 8.708(7) Å, c = 24.195(19) Å, α = ß = 90°, and γ = 120°. The X-ray absorption fine structure (XAFS) technique was also used to extract the local atomic structures. The in situ X-ray diffraction (XRD) technique was used to monitor the structural evolution of the as-prepared ZIF-L in a temperature range from room temperature to 600 °C. The results show that the sample experiences a change process from the initial ZIF-L orthorhombic phase (<210 °C), to the ZIF-L300 hexagonal phase (∼300 °C), then to an amorphous phase (∼390 °C), and finally to a zincite ZnO phase (>420 °C). These sorts of structural information are helpful to the application of ZIF materials and enrich the knowledge of the thermal stability of ZIF materials.

16.
Ann Clin Microbiol Antimicrob ; 22(1): 10, 2023 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-36710337

RESUMEN

BACKGROUND: Carbapenem resistant Enterobacteriaceae (CRE) colonization is a risk factor for CRE infection. CRE infection results in an increase in mortality in patients with cirrhosis. However, minimal data regarding the prevalence and the risk factors of CRE colonization in patients with liver disease yet without liver transplantation are available. The present study aimed to investigate the prevalence, risk factors and molecular epidemiology characteristics of CRE fecal carriage among patients with liver disease. METHODS: Stool specimens from 574 adult inpatients with liver disease were collected from December 2020 to April 2021. CRE were screened using selective chromogenic agar medium and identified by the Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS). Antimicrobial susceptibility was determined using the broth microdilution method. Carbapenemase genes were characterized by polymerase chain reaction (PCR) and DNA sequencing. Multilocus sequence typing (MLST) was performed for Carbapenem Resistant Klebsiella pneumoniae (CR-KPN) isolates and Carbapenem Resistant Escherichia Coli (CR-ECO) isolates. RESULTS: The total number of stool specimens (732) were collected from 574 patients with liver disease. 43 non-duplicated CRE strains were isolated from 39 patients with a carriage rate of 6.79% (39/574). The carriage rate was 15.60% (17/109) in patients with acute-on-chronic liver failure (ACLF). Multivariate analysis indicated that ACLF (P = 0.018), the history of pulmonary infection within past 3 months (P = 0.001) and the use of third generation cephalosporin/ß-lactamases inhibitor within past 3 months (P = 0.000) were independent risk factors of CRE colonization in patients with liver disease. Klebsiella Pnuemoniae (KPN) (51.28%) and Escherichia coli (ECO) (30.77%) were main strains in these patients. All CRE strains showed high resistance to most antimicrobials except for polymyxin B and tigecycline. Most (83.72%, 36/43) of the CRE carried carbapenemase genes. blaKPC-2 was the major carbapenemase gene. The molecular epidemiology of KPN were dominated by ST11, while the STs of ECO were scattered. CONCLUSIONS: The present study revealed that CRE fecal carriage rates were higher in patients with ACLF than in patients without liver failure. ACLF, the history of pulmonary infection within past 3 months and the use of third generation cephalosporin/ß-lactamases inhibitor within past 3 months were independent risk factors of CRE colonization in patients with liver disease. Regular CRE screening for hospitalized patients with liver disease should be conducted to limit the spread of CRE strain.


Asunto(s)
Enterobacteriaceae Resistentes a los Carbapenémicos , Infecciones por Enterobacteriaceae , Hepatopatías , Adulto , Humanos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Infecciones por Enterobacteriaceae/epidemiología , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Carbapenémicos/farmacología , Epidemiología Molecular , Tipificación de Secuencias Multilocus , beta-Lactamasas/genética , Escherichia coli , Klebsiella pneumoniae , Factores de Riesgo , Cefalosporinas
17.
Int J Mol Sci ; 24(11)2023 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-37298379

RESUMEN

With the demand for more efficient and safer therapeutic drugs, targeted therapeutic peptides are well received due to their advantages of high targeting (specificity), low immunogenicity, and minimal side effects. However, the conventional methods of screening targeted therapeutic peptides in natural proteins are tedious, time-consuming, less efficient, and require too many validation experiments, which seriously restricts the innovation and clinical development of peptide drugs. In this study, we established a novel method of screening targeted therapeutic peptides in natural proteins. We also provide details for library construction, transcription assays, receptor selection, therapeutic peptide screening, and biological activity analysis of our proposed method. This method allows us to screen the therapeutic peptides TS263 and TS1000, which have the ability to specifically promote the synthesis of the extracellular matrix. We believe that this method provides a reference for screening other drugs in natural resources, including proteins, peptides, fats, nucleic acids, and small molecules.


Asunto(s)
Ácidos Nucleicos , Sericinas , Sericinas/farmacología , Transcriptoma , Péptidos/farmacología , Péptidos/uso terapéutico , Péptidos/química , Inmunoprecipitación
18.
Angew Chem Int Ed Engl ; 62(13): e202300260, 2023 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-36746758

RESUMEN

2,7,12,17-Tetrakis(pinacolatoboryl) NiII porphyrin 5 Ni was synthesized in 75 % yield by Ir-catalyzed borylation of porphine followed by NiII metalation and has been demonstrated to be a useful synthon, giving 2,7,12,17-tetraaryated NiII porphyrins 6 a-d, peripherally octaarylated NiII porphyrins 8 a-d, quadruply bridged face-to-face non-offset NiII -porphyrin dimer 12, and cross-shaped ß-meso singly linked porphyrin pentamers and nonamers. Oxidation of cross-shaped ß-meso singly linked porphyrin pentamers 14 Ni and 14 Zn gave fused pentameric tapes 15 Ni and 15 Zn. The structures of 12, 14 Zn, and 15 Ni have been revealed by X-ray diffraction analysis. Optical separation of 12 has been accomplished, showing a bisignate coupling pattern for exciton-coupled blue-shifted Soret band. Pentameric porphyrin tape 15 Zn exhibits a red-shifted absorption band at 1156 nm and seven reversible redox waves.

19.
Chemistry ; 28(61): e202202056, 2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36053242

RESUMEN

Herein, a host-guest interaction-controlled photoproduct created by using cucurbit[7]uril (Q[7])-based pseudorotaxane structures is reported. The assembly exhibited controlled behavior towards the reduction of the ethylene (C=C) bond in the tetrakis(pyridin-4-yl)ethylene (TPyE) guest molecule under UV light irradiation. This can be attributed to the Q[7] encapsulation masking the four pyridinium arms of the guest, which inhibits planarization of the TPyE core to form the cyclization product. In particular, the strong affinity of Q[7] for the butyl-substituted guest (TPyE-4C) led to an unusual radical fluorescence emission of the photoirradiation-triggered intermediate of the guest molecule being observed in aqueous solution. This work provides a valuable paradigm and new insight for macrocycle-based host-guest interactions in supramolecular catalysis and luminescent radical materials.


Asunto(s)
Hidrocarburos Aromáticos con Puentes , Imidazoles , Hidrocarburos Aromáticos con Puentes/química , Imidazoles/química , Espectrometría de Fluorescencia , Etilenos
20.
Angew Chem Int Ed Engl ; 61(33): e202206899, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35654739

RESUMEN

The one-pot self-coupling reaction of 3-amino-5-bromo-BODIPY 9 under Buchwald-Hartwig amination conditions gave nitrogen-bridged cyclic BODIPY tetramer 10, pentamer 11, and hexamer 12. Oxidation of 10, 11, and 12 in the presence of alkali metal ions provided 13, 15, and 16, respectively, as the first examples of expanded azaporphyrins possessing more than six pyrrole rings. Curiously, the oxidation even in the absence of alkali metal ions gave the same complexes as a result of spontaneous complexation. 10-12 showed large association constants (104 -106  M-1 ) with K+ and Na+ , but the spontaneous complexations were not observed, indicating the extremely high affinities of 13-16 toward alkali metal ions, which can be ascribed to the multiple and effective ion-dipole interaction of the alkali metal ion with the negatively polarized F atoms of the BF2 walls surrounding the cavity. Importantly, 13, 14, and 15 show diatropic ring currents as a result of global aromaticity.

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