Isolation of two-coordinate compounds of heavier Group 15 elements in low oxidation state is challenging due to the preferential formation of dimers or oligomers. Herein, we report the first examples of donor-stabilized two-coordinate Sb(I) and Bi(I) ions. The reduction of antimony and bismuth trihalides with KC8 in the presence of cyclic alkyl(amino) carbene (cAAC) afforded Sb(I) and Bi(I) cations in the form of triflate salts [(cAAC)2Sb][OTf] (1) and [(cAAC)2Bi][OTf] (2). Compounds 1 and 2 belong to a new class of acyclic cations of Group 15 with eight valence electrons and are heavier valence isoelectronic analogues of carbones. Both compounds are isolated and well-characterized by NMR spectroscopy, cyclic voltammetry, single-crystal X-ray diffraction, and computational studies.The aromatic 14π meso-tetraaryl triphyrin(2.1.1)s were switched to stable antiaromatic 16π P(V) complexes of triphyrin(2.1.1) by refluxing free base triphyrin(2.1.1)s with PCl3 in a mixture of solvents toluene/triethylamine for 4 h. The P(V) triphyrin(2.1.1)s were characterized by high-resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR) spectroscopy and their properties were studied in detail by absorption, electrochemical, and density functional theory (DFT) studies. The studies suggested that PCl3 reduces 14π triphyrins to 16π triphyrins, which were then complexed to form stable antiaromatic P(V) complexes.Open shell organic molecules bearing π-cores are of great interest for optical, electronic, and magnetic applications but frequently suffer fast decomposition or lack synthetic accessibility. In this regard, nitronyl nitroxides are promising candidates for stable (bi-)radicals due to their high degree of spin delocalization along the O-N-C-N-O pentad unit. Unfortunately, they are limited to electron-rich systems so far. https://www.selleckchem.com/products/avotaciclib-trihydrochloride.html To overcome this limitation, we developed a synthetic procedure for the twofold spin decoration of electron-poor chromophores (Ered = -1158 mV) with nitronyl nitroxide radical moieties via selective deprotection/oxidation of the respective silylated precursors with boron fluoride and subsequent quenching with tetraethyl orthosilicate. Nitronyl nitroxide biradicals PBI-NN, IIn-NN, PhDPP-NN, ThDPP-NN, and FuDPP-NN bridged by perylene bisimide (PBI), isoindigo (IIn), and diketopyrrolopyrrole (DPP) pigment colorants were finally obtained as bench stable compounds after periodate oxidation with yields of 60-81%. The absorption spectral signatures of the chromophores remain preserved in the open shell state and match the ones of the pristine parent compounds, which allowed an a priori prediction of their optical properties. Consequently, we achieved twofold spin labeling while keeping the intrinsic properties of the electron deficient chromophores intact.Based on first-principles calculations with the DFT + U method, the couplings of lattice, charge, spin, and electronic behaviors underlying the Eu-Mn charge transfer in a strongly correlated system of EuMnO3 were investigated. The potential valence transition from Eu3+/Mn3+ to Eu2+/Mn4+ was observed in a compressed lattice with little distortions, which is achieved under hydrostatic pressure and external strain. The intraplane antiferromagnetism (AFM) of Mn is proved to be instrumental in the emergence of Eu2+. Furthermore, we calculated the magnetic exchange interactions within two equilibrium structures of Eu3+Mn3+O3 and Eu2+Mn4+O3. Mn-Mn ferromagnetic exchange in the ab-plane is enhanced strongly in the Eu2+Mn4+O3 structure, contributing to the existence of mixed states. The versatile electronic structures were obtained within the Eu2+Mn4+O3 phase by imposing different magnetic configurations on the Eu and Mn sublattice, attributed to the coupling of charge transfer and magnetic orderings. It is found that the intraplane ferromagnetic ordering of Mn leads to a metallic electronic structure with the coexistence of Eu2+ and Eu3+, while the intraplane AFM Mn spin ordering leads to insulating states only with Eu2+. Notably, a half-metallic characteristic emerges at the magnetic ground state of CF ordering (C-type AFM for the Eu sublattice and ferromagnetic for the Mn sublattice), which makes such a supposed phase more intriguing than the conventional experimental phase. Additionally, the mixture of delocalized 4f with 5d states of Eu in the background of Mn 3d and O 2p orbitals implies a pathway of Eu 4f 5d ↔ O 2p ↔ Mn 3d for charge transfer between Eu and Mn. Our calculation shows that the Eu-Mn charge transfer could be expected in compressed EuMnO3 and the introduction of Eu2+ 4f states near the Fermi level plays an important role in manipulating the interlinks of charge and spin together with electronic behaviors.Algal bloom microalgae are abundant in polluted water systems, but their biocrude oil production potential via hydrothermal liquefaction (HTL) is limited. This study proposed a novel process that combined biological (dark fermentation) and thermochemical (HTL) techniques aimed at changing the feedstock characteristics to be more suitable for thermochemical conversion, herein named integrated dark fermentation-hydrothermal liquefaction (DF-HTL). DF-HTL conversion of algae significantly enhanced the biocrude oil yield (wt %), carbon content (mol), energy content (MJ), and energy conversion ratios by 9.8, 29.7, 40.0, and 61.0%, respectively, in comparison to the control. Furthermore, DF-HTL processing significantly decreased the aqueous byproduct yield (wt %), carbon content (mol), nitrogen content (mol), and ammonia content (mol) by 19.0, 38.4, 25.0, and 13.2%, respectively, in comparison to the control. Therefore, DF-HTL reduced the environmental impact associated with disposing of the wastewater byproduct. However, DF-HTL also augmented the nitrogen content (mol) of the biocrude oil by 42.2% in comparison to the control. The benefits of DF-HTL were attributed to the increased acid content, the incorporation of H2 as a processing gas, and the enhancement of the Maillard reaction, which shifted the distribution of reaction products from the aqueous phase to the biocrude oil phase. This article provides insights into the efficacy of a novel integrated biological-thermochemical processing method with distinct environmental and energetic advantages over conventional HTL that heightens the biocrude oil yield for feedstocks with a high carbohydrate and a high protein content.
Isolation of two-coordinate compounds of heavier Group 15 elements in low oxidation state is challenging due to the preferential formation of dimers or oligomers. Herein, we report the first examples of donor-stabilized two-coordinate Sb(I) and Bi(I) ions. The reduction of antimony and bismuth trihalides with KC8 in the presence of cyclic alkyl(amino) carbene (cAAC) afforded Sb(I) and Bi(I) cations in the form of triflate salts [(cAAC)2Sb][OTf] (1) and [(cAAC)2Bi][OTf] (2). Compounds 1 and 2 belong to a new class of acyclic cations of Group 15 with eight valence electrons and are heavier valence isoelectronic analogues of carbones. Both compounds are isolated and well-characterized by NMR spectroscopy, cyclic voltammetry, single-crystal X-ray diffraction, and computational studies.The aromatic 14π meso-tetraaryl triphyrin(2.1.1)s were switched to stable antiaromatic 16π P(V) complexes of triphyrin(2.1.1) by refluxing free base triphyrin(2.1.1)s with PCl3 in a mixture of solvents toluene/triethylamine for 4 h. The P(V) triphyrin(2.1.1)s were characterized by high-resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR) spectroscopy and their properties were studied in detail by absorption, electrochemical, and density functional theory (DFT) studies. The studies suggested that PCl3 reduces 14π triphyrins to 16π triphyrins, which were then complexed to form stable antiaromatic P(V) complexes.Open shell organic molecules bearing π-cores are of great interest for optical, electronic, and magnetic applications but frequently suffer fast decomposition or lack synthetic accessibility. In this regard, nitronyl nitroxides are promising candidates for stable (bi-)radicals due to their high degree of spin delocalization along the O-N-C-N-O pentad unit. Unfortunately, they are limited to electron-rich systems so far. https://www.selleckchem.com/products/avotaciclib-trihydrochloride.html To overcome this limitation, we developed a synthetic procedure for the twofold spin decoration of electron-poor chromophores (Ered = -1158 mV) with nitronyl nitroxide radical moieties via selective deprotection/oxidation of the respective silylated precursors with boron fluoride and subsequent quenching with tetraethyl orthosilicate. Nitronyl nitroxide biradicals PBI-NN, IIn-NN, PhDPP-NN, ThDPP-NN, and FuDPP-NN bridged by perylene bisimide (PBI), isoindigo (IIn), and diketopyrrolopyrrole (DPP) pigment colorants were finally obtained as bench stable compounds after periodate oxidation with yields of 60-81%. The absorption spectral signatures of the chromophores remain preserved in the open shell state and match the ones of the pristine parent compounds, which allowed an a priori prediction of their optical properties. Consequently, we achieved twofold spin labeling while keeping the intrinsic properties of the electron deficient chromophores intact.Based on first-principles calculations with the DFT + U method, the couplings of lattice, charge, spin, and electronic behaviors underlying the Eu-Mn charge transfer in a strongly correlated system of EuMnO3 were investigated. The potential valence transition from Eu3+/Mn3+ to Eu2+/Mn4+ was observed in a compressed lattice with little distortions, which is achieved under hydrostatic pressure and external strain. The intraplane antiferromagnetism (AFM) of Mn is proved to be instrumental in the emergence of Eu2+. Furthermore, we calculated the magnetic exchange interactions within two equilibrium structures of Eu3+Mn3+O3 and Eu2+Mn4+O3. Mn-Mn ferromagnetic exchange in the ab-plane is enhanced strongly in the Eu2+Mn4+O3 structure, contributing to the existence of mixed states. The versatile electronic structures were obtained within the Eu2+Mn4+O3 phase by imposing different magnetic configurations on the Eu and Mn sublattice, attributed to the coupling of charge transfer and magnetic orderings. It is found that the intraplane ferromagnetic ordering of Mn leads to a metallic electronic structure with the coexistence of Eu2+ and Eu3+, while the intraplane AFM Mn spin ordering leads to insulating states only with Eu2+. Notably, a half-metallic characteristic emerges at the magnetic ground state of CF ordering (C-type AFM for the Eu sublattice and ferromagnetic for the Mn sublattice), which makes such a supposed phase more intriguing than the conventional experimental phase. Additionally, the mixture of delocalized 4f with 5d states of Eu in the background of Mn 3d and O 2p orbitals implies a pathway of Eu 4f 5d ↔ O 2p ↔ Mn 3d for charge transfer between Eu and Mn. Our calculation shows that the Eu-Mn charge transfer could be expected in compressed EuMnO3 and the introduction of Eu2+ 4f states near the Fermi level plays an important role in manipulating the interlinks of charge and spin together with electronic behaviors.Algal bloom microalgae are abundant in polluted water systems, but their biocrude oil production potential via hydrothermal liquefaction (HTL) is limited. This study proposed a novel process that combined biological (dark fermentation) and thermochemical (HTL) techniques aimed at changing the feedstock characteristics to be more suitable for thermochemical conversion, herein named integrated dark fermentation-hydrothermal liquefaction (DF-HTL). DF-HTL conversion of algae significantly enhanced the biocrude oil yield (wt %), carbon content (mol), energy content (MJ), and energy conversion ratios by 9.8, 29.7, 40.0, and 61.0%, respectively, in comparison to the control. Furthermore, DF-HTL processing significantly decreased the aqueous byproduct yield (wt %), carbon content (mol), nitrogen content (mol), and ammonia content (mol) by 19.0, 38.4, 25.0, and 13.2%, respectively, in comparison to the control. Therefore, DF-HTL reduced the environmental impact associated with disposing of the wastewater byproduct. However, DF-HTL also augmented the nitrogen content (mol) of the biocrude oil by 42.2% in comparison to the control. The benefits of DF-HTL were attributed to the increased acid content, the incorporation of H2 as a processing gas, and the enhancement of the Maillard reaction, which shifted the distribution of reaction products from the aqueous phase to the biocrude oil phase. This article provides insights into the efficacy of a novel integrated biological-thermochemical processing method with distinct environmental and energetic advantages over conventional HTL that heightens the biocrude oil yield for feedstocks with a high carbohydrate and a high protein content.
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