Amino-λ³-iodane-Enabled Electrophilic Amination of Arylboronic Acid Derivatives

Kiyokawa K., Kawanaka K., Minakata S.. Amino-λ3-iodane-Enabled Electrophilic Amination of Arylboronic Acid Derivatives. Angewandte Chemie - International Edition 63, e202319048 (2024); https://doi.org/10.1002/anie.202319048.In this report, we describe the use of amino-λ³-iodanes in the electrophilic amination of arylboronic acids and boronates. Iodine(III) reagents with transferable amino groups, including one with an NH₂ group, were synthesized and used in the amination, allowing the synthesis of a wide range of primary and secondary (hetero)arylamines. Mechanistic studies by DFT calculations indicate that the reaction proceeds through an electrophilic amination process from a tetravalent borate complex with a B−N dative bond

Palladium-catalyzed regioselective and stereo-invertive ring-opening borylation of 2-arylaziridines with bis(pinacolato)diboron: Experimental and computational studies

A palladium catalyzed regioselective borylative ring opening reaction of 2-arylaziridines to give β-amino-β-arylethylborates was developed. The reaction reported herein represents the first example of ring-opening borylation of non-vinylic aziridines and direct borylative C(sp3)-N bond cleavage of neutral organic substrates. NMR studies and density functional theory (DFT) calculations suggested that the active intermediate for the reaction is a PdL2 complex [L = P(t-Bu)2Me]. The multi-component artificial force-induced reaction method (MC-AFIR) located the transition states for the regioselectivity-determining aziridine ring opening that proceeds in an SN2 fashion, and explained the selectivity of the reaction. The full catalytic cycle consists of a selectivity-determining aziridine ring opening (oxidative addition), a proton transfer, phosphine ligand dissociation from the catalyst, boron-boron bond cleavage, and reductive elimination. Water is important to the drive the transmetalation step. The calculated overall mechanism and selectivity are consistent with the experimental results

Conformationally-flexible and moderately electron-donating units-installed D–A–D triad enabling multicolor-changing mechanochromic luminescence, TADF and room-temperature phosphorescence

A novel twisted donor–acceptor–donor (D–A–D) π-conjugated compound that contains flexible and moderately-electron-donating units has been designed and synthesized. It exhibited not only multi-color-changing mechanochromic luminescence and thermally activated delayed fluorescence, but also, unexpectedly, room-temperature phosphorescence in a host layer

Anion-Responsive Colorimetric and Fluorometric Red-Shift in Triarylborane Derivatives: Dual Role of Phenazaborine as Lewis Acid and Electron Donor

Aota N., Nakagawa R., de Sousa L.E., et al. Anion-Responsive Colorimetric and Fluorometric Red-Shift in Triarylborane Derivatives: Dual Role of Phenazaborine as Lewis Acid and Electron Donor. Angewandte Chemie - International Edition , (2024); https://doi.org/10.1002/anie.202405158.Photophysical modulation of triarylboranes (TABs) through Lewis acid-base interactions is a fundamental approach for sensing anions. Yet, design principles for anion-responsive TABs displaying significant red-shift in absorption and photoluminescence (PL) have remained elusive. Herein, a new strategy for modulating the photophysical properties of TABs in a red-shift mode has been presented, by using a nitrogen-bridged triarylborane (1,4-phenazaborine: PAzB) with a contradictory dual role as a Lewis acid and an electron donor. Following the strategy, PAzB derivatives connected with an electron-deficient azaaromatic have been developed, and these compounds display a distinct red-shift in their absorption and PL in response to an anion. Spectroscopic analyses and quantum chemical calculations have revealed the formation of a tetracoordinate borate upon the addition of fluoride, narrowing the HOMO–LUMO gap and enhancing the charge-transfer character in the excited state. This approach has also been demonstrated in modulating the photophysical properties of solid-state films

Electrochemical and Spectroelectrochemical Comparative Study of Macrocyclic Thermally Activated Delayed Fluorescent Compounds: Molecular Charge Stability vs OLED EQE Roll-Off

In this work, we present how a small change in molecular structure can affect the electrochemical stability of organic compounds. A new electron donor-acceptor-donor-acceptor (D-A-D-A) macrocyclic π-conjugated compound (tBuMC) comprising of dibenzophenazine as As and N,N’-bis(t-butylphenyl)-p-phenylenediamines as Ds has been synthesized. The photophysical investigation uncovered that tBuMC showed thermally activated delayed fluorescence and that the organic light-emitting diodes (OLEDs) fabricated with tBuMC as the emitter achieved high external quantum efficiency (EQEs) of ca. 10%. However, the OLED with tBuMC showed a slightly lower EQE than that of the OLED with MC (11.6%) and showed greater EQE roll-off. Comparative studies on electrochemical properties of tBuMC, MC, and a linear analogue (Linear) revealed the introduction of t-Bu groups in the D-A-D-A scaffold causes a significant change in redox behavior. Full electrochemical and spectroelectrochemical studies gave clues to understand how the steric hindering group is affecting the charge distribution in the new molecules which results in a significant difference in the OLED roll-off. The electrochemical investigations together with UV-Vis-NIR and EPR analyses supported by quantum chemical theoretical calculations were performed, which provided us insights on the effect of structural modification on the redox properties of the D-A-D-A scaffold.This is the peer reviewed version of the following article: A. Nyga, S. Izumi, H. F. Higginbotham, P. Stachelek, S. Pluczyk, P. de Silva, S. Minakata, Y. Takeda, P. Data, Asian J. Org. Chem. 2020, 9, 2153., which has been published in final form at https://doi.org/10.1002/ajoc.202000475. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving

3,11-Diaminodibenzo[a,j]phenazine: Synthesis, Properties, and Applications to Tröger's Base-Forming Ladder Polymerization

This is the accepted version of the following article: Izumi S., Inoue K., Nitta Y., et al. 3,11-Diaminodibenzo[a,j]phenazine: Synthesis, Properties, and Applications to Tröger's Base-Forming Ladder Polymerization. Chemistry - A European Journal 29, e202202702 (2023), which has been published in final form at https://doi.org/10.1002/chem.202202702. This article may be used for non-commercialpurposes in accordance with the Wiley Self-ArchivingPolicy. [https://authorservices.wiley.com/author-resources/Journal-Authors/licensing/self-archiving.html]A new class of diamino-substituted π-extended phenazine compound was synthesized, and its photophysical properties were investigated. The U-shaped diaminophenazine displayed photoluminescence in solution with moderate quantum yield. The diamino aromatic compound was found applicable to the poly-condensation with formaldehyde to form Tröger's base ladder polymer. The obtained microporous ladder polymer features high CO2 adsorption selectivity against N2, most likely due to the presence of basic nitrogen atoms in the phenazine rings

The regioisomeric effect on the excited-state fate leading to room-temperature phosphorescence or thermally activated delayed fluorescence in a dibenzophenazine-cored donor-acceptor-donor system

Hosono T., Decarli N.O., Crocomo P.Z., et al. The regioisomeric effect on the excited-state fate leading to room-temperature phosphorescence or thermally activated delayed fluorescence in a dibenzophenazine-cored donor-acceptor-donor system. Journal of Materials Chemistry C 10, 4905 (2022); https://doi.org/10.1039/D1TC05730H.Exploring the design principle for switching between thermally activated delayed fluorescence (TADF) and room temperature phosphorescence (RTP) is a fundamentally important research to develop triplet-mediated photofunctional organic materials. Herein systematic studies on the regioisomeric and substituent effects in a twisted donor-acceptor-donor (D-A-D) molecular scaffold (A = dibenzo[a,j]phenazine; D = dihydrophenazasiline) on the fate of its excited state have been performed. The study revealed that regioisomerism clearly affects the emission behavior of the D-A-D compounds. Moreover, distinct differences in TADF, dual TADF & RTP, and dual RTP were observed, depending on the host used. Furthermore, organic light-emitting diodes (OLEDs) fabricated with the developed emitters achieved high external quantum efficiencies (EQEs) of up to 7.4% for RTP-based OLEDs

Pharmacist-physician collaborative care for outpatients with left ventricular assist devices using a cloud-based home medical management information-sharing system: a case report

[Background] The standard anticoagulation therapy for patients implanted with left ventricular assist devices (LVADs) includes warfarin therapy. We developed a cloud-based home medical management information-sharing system named as LVAD@home. The LVAD@home system is an application designed to be used on iPad tablet computers. This system enables the sharing of daily information between a patient and care providers in real time. In this study, we reported cases of outpatients with LVADs using this system to manage anticoagulation therapy. [Case presentation] The patient, a man in his 40s with end-stage heart failure owing to non-ischemic dilated cardiomyopathy, underwent LVAD implantation and warfarin was started on postoperative day 1. He started to use LVAD@home to manage warfarin therapy after discharge (postoperative day 47). He sent his data to care providers daily. By using this system, the pharmacist observed his signs of reduced dietary intake 179 days after discharge, and after consulting the physician, told the patient to change the timing of the next measurement earlier than usual. On the next day, the prothrombin time-international normalized ratio increased from 2.0 to 3.0, and thus the dose was decreased by 0.5 mg. Four patients used this system to monitor warfarin therapy from October 2015 to March 2018. In these patients, the time in therapeutic range was 90.1 ± 1.3, which was higher than that observed in previous studies. Additionally, there were no thromboembolic events or bleeding events. [Conclusions] The cloud-based home management system can be applied to share real-time patient information of factors, including dietary intake that interact with warfarin. It can help to improve long-term anticoagulation outcomes in patients implanted with LVAD