Article
Chemistry, Organic
Joseph P. Gillions, Salma A. Elsherbeni, Laura Winfrey, Lei Yun, Rebecca L. Melen, Louis C. Morrill, Alexander P. Pulis
Summary: C-H functionalization is an important area in synthetic methodology, and electron-deficient organoboranes have great potential in mediating hydride abstraction from alpha-amino C-H bonds. This review covers recent advances in organoborane-mediated hydride abstraction, focusing on their catalytic applications in alpha- or beta-functionalization, alpha,beta-difunctionalization, and amine dehydrogenation.
Review
Chemistry, Inorganic & Nuclear
Krzysztof Fink, Mariusz Uchman
Summary: Boron cluster compounds are inorganic compounds with unique structures and properties that show promising antimicrobial activity and low sensitivity to pathogen resistance mechanisms. Their derivatives are effective against both standard and multi-drug resistant strains of pathogens.
COORDINATION CHEMISTRY REVIEWS
(2021)
Article
Multidisciplinary Sciences
Jordi Poater, Clara Vinas, Miquel Sola, Francesc Teixidor
Summary: This study investigates the possibility of 3D/2D aromatic fusions and their relationship to electronic delocalization. While 2D/2D and 3D/3D aromatic fusions have been synthesized, the ineffective overlap between the pi-MOs of planar species and the n + 1 molecular orbitals in the aromatic cage makes 3D/2D aromatic combination impossible.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Fangxiang Sun, Shuaimin Tan, Hou-Ji Cao, Jingkai Xu, Vladimir I. Bregadze, Deshuang Tu, Changsheng Lu, Hong Yan
Summary: This research proposes a new molecular design strategy for achieving AIE properties by combining three-dimensional aromatic boron clusters of carboranes with vinyl group(s). A efficient synthesis method for boron cluster-based AIEgens is developed.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Meng Chen, Jingkai Xu, Deshi Zhao, Fangxiang Sun, Songlin Tian, Deshuang Tu, Changsheng Lu, Hong Yan
Summary: This study presents a photocatalytic B-C coupling reaction for the selective functionalization of carboranes. The reaction involves the photo-induced decarboxylation of carborane carboxylic acids and generates boron vertex-centered carboranyl radicals. The reaction can be conducted under mild conditions and allows the synthesis of various functionalized carboranes, including a highly efficient blue emitter and a drug candidate for boron neutron capture therapy.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Inorganic & Nuclear
Chaofan Sun, Ju-You Lu, Jian Lu
Summary: Efficient Pd-catalyzed regioselective B(6)-H phosphorization of nido-carboranes via cascade deboronation/B-H activation with various phosphines using 3-methylpyridine or isoquinoline as a directing group in combination with pyridine ligands has been developed, affording unprecedented B(6)-phosphinated nido-carborane derivatives with high selectivity in a simple one-pot process.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Manjur O. Akram, John R. Tidwell, Jason L. Dutton, Caleb D. Martin
Summary: The synthesis of a single site neutral Lewis superacid, tris(ortho-carboranyl)borane (BoCb(3)), was achieved in one pot from commercially available materials. It was confirmed to be a Lewis superacid due to its high fluoride ion affinity (FIA), and exhibited stronger Lewis acidity compared to widely used fluorinated aryl boranes, as evidenced by the Gutmann-Beckett method and adducts with Lewis bases. The unusually high Lewis acidity can be rationalized by the electron-withdrawing effect of ortho-carborane and lack of pi-delocalization of the LUMO. Catalytic studies demonstrated that BoCb(3) is a superior catalyst for promoting C-F bond functionalization reactions compared to tris(pentafluorophenyl)borane [B(C6F5)(3)].
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Harrison A. Mills, Samihat Rahman, Rachel Zigelstein, Hao Xu, Bryton R. Varju, Timothy P. Bender, Mark W. B. Wilson, Dwight S. Seferos
Summary: Conjugated macromolecules have a rich history in chemistry. Researchers have synthesized a new type of molecular dyads, consisting of sequence-defined oligomers and small-molecule acceptors. By controlling the sequence and length of the oligomers, the impact on the transfer efficiency of photoexcited states has been explored, highlighting the significance in studying light harvesting and photocatalysis.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Inorganic & Nuclear
Andrey V. Protchenko, M. Angeles Fuentes, Jamie Hicks, Caitilin McManus, Remi Tirfoin, Simon Aldridge
Summary: The reaction of boryl-substituted stannylene with carbon dioxide proceeds via pathways involving insertion into the Sn-B bonds. Several different products can be derived from this reaction, including boryl(borylcarboxylate)ester and bis(borylcarboxylate) stannylene complexes. The possibility of extrusion of CO from the reaction products to generate boryloxy systems has also been observed.
DALTON TRANSACTIONS
(2021)
Article
Crystallography
Albert Ferrer-Ugalde, Arantzazu Gonzalez-Campo, Jose Giner Planas, Clara Vinas, Francesc Teixidor, Isabel M. Saez, Rosario Nunez
Summary: A new set of mesomorphic materials is described, in which o-carborane clusters are covalently bonded to cholesteryl benzoate moieties through a designed linker. Compounds M2 and M3 exhibit chiral nematic phases, with M3 also displaying a blue phase, while M4 does not show liquid crystal behavior.
Article
Chemistry, Multidisciplinary
Ryo Miyajima, Yuuki Ooe, Tomoaki Miura, Tadaaki Ikoma, Hajime Iwamoto, Shin-ya Takizawa, Eietsu Hasegawa
Summary: Triarylamine-substituted benzimidazoliums (BI+- PhNAr2), new electron donor-acceptor dyad molecules, were synthesized and their photocatalytic properties for reductive organic transformations were explored. The results show that irradiation of BI+-PhNAr2 promotes photoinduced intramolecular electron transfer, forming a long-lived charge shifted state. Among the benzimidazoliums explored, the bromo-substituted analogue BI+-PhN(C6H4Br-p)2 in conjunction with BIH-Ph demonstrates the most consistent catalytic performance.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Organic
Ekaterina S. Kudriashova, Margarita A. Yarushina, Andrei E. Gavryushin, Ivan D. Grishin, Yulia B. Malysheva, Vasilii F. Otvagin, Alexey Yu. Fedorov
Summary: We report an unusual one-pot preparation of α-benzyl-substituted conjugated enals via ZnCl2/LiCl/H2O-mediated transformation of styrenes. Through experimental and computational studies, we propose an underlying mechanism involving electrophilic addition and hydride transfer with iminium cations. The effect of the LiCl/ZnCl2/H2O combination on the reaction yield and the activation of iminium electrophile have been demonstrated.
Article
Chemistry, Multidisciplinary
Daisuke Uraguchi, Kohsuke Kato, Takashi Ooi
Summary: An o-quinone methide (o-QM) with an overcrowded olefinic framework is introduced, showing dehydridation activity due to its enhanced zwitterionic character, especially under photoexcitation. Experimental analysis and density functional theory calculations provide mechanistic insights, revealing that the o-QM operates in dehydridative catalysis for the oxidation of benzylic secondary alcohols.
Article
Chemistry, Multidisciplinary
Ziyan Zhang, Vladimir Gevorgyan
Summary: A mild palladium hydride-catalyzed difunctionalization of conjugated dienes and enynes is reported. This method enables the chemoselectivity switch of the initial hydropalladation step by enhancing the hydricity of PdH species with visible light, allowing for cascade annulation of various easily available and abundant substrates, such as acrylic acids, acrylic amides, and Baylis-Hillman adducts, towards a wide range of alkenyl or alkynyl lactones, lactams, and tetrahydrofurans.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Cangtao Yin, Gabor Czako
Summary: The recently-developed high-level full-dimensional spin-orbit-corrected potential energy surfaces for the reactions of HX with C2H5 are improved by adding new geometries with higher energies. Quasi-classical trajectory simulations show that as collision energy increases, the probability of the H-abstraction reaction pathway decreases while the reactivity of the X-abstraction reaction pathway increases. Excitation in HX vibrational mode helps both reaction pathways, but more for X-abstraction.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Jan Schulz, Reike Clauss, Aleksandr Kazimir, Sieglinde Holzknecht, Evamarie Hey-Hawkins
Summary: The synthesis of B9-Phos ligands with two carboranyl moieties and bulky electron-donating substituents, previously deemed unattainable, is reported. The electrochemical properties of B9-Phos ligands were investigated, showing the ability of mesityl derivatives to form stabilized phosphoniumyl radical cations. The B9-Phos ligands possess a highly electron-releasing character surpassing that of alkyl phosphines and commonly used N-heterocyclic carbenes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Nils Koenig, Yokari Godinez-Loyola, Yang Fangshun, Christian Laube, Michael Laue, Peter Loennecke, Cristian A. Strassert, Evamarie Hey-Hawkins
Summary: Phosphole oxides react with sulfonyl isocyanates, forming sulfonylimino phospholes in high yields. This facile modification allows for the synthesis of new phosphole-based aggregation-induced emission (AIE) luminogens with high fluorescence quantum yields in the solid state. Changing the chemical environment of the phosphorus atom of the phosphole framework results in a significant red-shift of the fluorescence maximum.
Article
Pharmacology & Pharmacy
Philipp Stockmann, Lydia Kuhnert, Wencke Leinung, Cathleen Lakoma, Birte Scholz, Svetlana Paskas, Sanja Mijatovic, Danijela Maksimovic-Ivanic, Walther Honscha, Evamarie Hey-Hawkins
Summary: The overexpression of ATP-binding cassette (ABC) transporter proteins, particularly ABCG2, in cancer cells is a major cause of multidrug resistance (MDR) and the failure of chemotherapeutic treatments. Inhibition of ABCG2 activity during chemotherapy has the potential to reverse MDR and improve the efficacy of anti-cancer agents. However, the development of selective and non-toxic inhibitors of ABCG2 has been challenging, with limited success in clinical applications. This study focuses on the synthesis and evaluation of carboranyl quinazoline-based inhibitors of ABCG2, identifying a promising compound, DMQCd, which exhibits strong inhibitory effects and the ability to reverse MDR mediated by BCRP.
Article
Chemistry, Inorganic & Nuclear
Alexandra Hildebrand, Peter Loennecke, Luminita Silaghi-Dumitrescu, Evamarie Hey Hawkins
Summary: The bulky tritopic phosphanylthiolato pincer ligand (Tipp)P(2-SHC6H4)2 (Tipp = 2,4,6-iPr3C6H2) (TippPS2H2) reacts with nickel dichloride to give the dinuclear nickel(II) complex [Ni{(Tipp)P(mu-2-SC6H4)2-kappa 3S,S',P}]2 (1).
INORGANICA CHIMICA ACTA
(2023)
Article
Chemistry, Multidisciplinary
Shrouq Mujahed, Maria S. S. Richter, Evgueni Kirillov, Evamarie Hey-Hawkins, Dmitri Gelman
Summary: In this study, we demonstrate the successful application of a high-valent Ru-IV bifunctional catalyst for mild hydrogenation of carbonates. Our experimental and theoretical investigations reveal that the hydrogenation mechanism involves an unusual formally zwitterionic Ru-IV complex. Our findings suggest that the positively charged metal center enhances hydrogen coordination, while the proximate negatively charged ligand site facilitates efficient catalysis through heterolytic H-2 bond activation.
ISRAEL JOURNAL OF CHEMISTRY
(2023)
Article
Chemistry, Medicinal
Lea Ueberham, Daniel Guendel, Martin Kellert, Winnie Deuther-Conrad, Friedrich-Alexander Ludwig, Peter Loennecke, Aleksandr Kazimir, Klaus Kopka, Peter Brust, Rares-Petru Moldovan, Evamarie Hey-Hawkins
Summary: The synthesis and characterization of carborane-based 1,8-naphthyridinones and thiazoles as novel CB2R ligands was reported in this study. These compounds showed low nanomolar CB2R affinity, with LUZ5 exhibiting the highest affinity. An automated radiosynthesizer was used to obtain [18F]LUZ5-d8 with high radiochemical yield and purity. In vivo evaluation demonstrated the improved metabolic stability of [18F]LUZ5-d8 compared to [18F]JHU94620, and PET experiments in rats showed high uptake in spleen and low uptake in brain. The introduction of a carborane moiety is a useful strategy for modifying CB2R ligands and developing high-affinity CB2R ligands.
JOURNAL OF MEDICINAL CHEMISTRY
(2023)
Article
Medicine, Research & Experimental
Jelena Matovic, Katayun Bahrami, Philipp Stockmann, Iris K. . Sokka, You Cheng Khng, Mirkka Sarparanta, Evamarie Hey-Hawkins, Jarkko Rautio, Filip S. Ekholm
Summary: Boron neutron capture therapy (BNCT) is a cancer treatment that uses boron delivery agents to selectively eradicate tumor cells. In this study, we focus on a GLUT1-targeting strategy to BNCT and synthesize carborane-bearing D-galactose, D-mannose, and D-allose as potential delivery agents. We find that these agents exhibit significantly improved boron delivery capacity compared to clinically approved agents in vitro, laying the groundwork for future preclinical assessment studies.
MOLECULAR PHARMACEUTICS
(2023)
Correction
Pharmacology & Pharmacy
Aleksandr Kazimir, Benedikt Schwarze, Peter Loennecke, Sanja Jelaca, Sanja Mijatovic, Danijela Maksimovic-Ivanic, Evamarie Hey-Hawkins
Article
Biochemistry & Molecular Biology
Ivana Predarska, Mohamad Saoud, Ibrahim Morgan, Peter Loennecke, Goran N. Kaluderovic, Evamarie Hey-Hawkins
Summary: In this study, triphenyltin(IV) derivatives of non-steroidal anti-inflammatory drugs were synthesized and evaluated for their antiproliferative effects on breast carcinoma cells. The tin(IV) complexes showed potent activity and inhibited cell proliferation possibly by downregulating nitric oxide synthase expression.
Article
Pharmacology & Pharmacy
Liridona Useini, Teodora Komazec, Markus Laube, Peter Loennecke, Jonas Schaedlich, Sanja Mijatovic, Danijela Maksimovic-Ivanic, Jens Pietzsch, Evamarie Hey-Hawkins
Summary: Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used for pain, fever, and inflammation, and have reported antitumor properties. Selectivity for the COX-2 isoform of NSAIDs is of high interest to reduce off-target effects. Modified NSAIDs using carborane clusters show altered selectivity profile and isonimesulide and its carborane derivatives exhibit stronger antitumor potential compared to nimesulide and isonimesulide. Additionally, replacement of the phenyl ring with a carborane moiety shifts the COX activity from nonactive to active compounds.
ADVANCED THERAPEUTICS
(2023)
Article
Chemistry, Medicinal
Philipp Stockmann, Lydia Kuhnert, Tamara Krajnovic, Sanja Mijatovic, Danijela Maksimovic-Ivanic, Walther Honscha, Evamarie Hey-Hawkins
Summary: The study introduces a new compound DMQCd, which shows promising results in improving multidrug resistance in cancer treatment by inhibiting the human ABCG2 transporter. The results indicate that DMQCd exhibits superior cytotoxicity and ability to reverse resistance.
Article
Chemistry, Medicinal
Svetlana Paskas, Philipp Stockmann, Sanja Mijatovic, Lydia Kuhnert, Walther Honscha, Evamarie Hey-Hawkins, Danijela Maksimovic-Ivanic
Summary: The ABCG2 transporter protein plays an important role in multidrug resistance and targeting its activity can improve cancer therapies. This study evaluates potential inhibitors of ABCG2 and their toxicity towards cancer cells expressing ABCG2. The results show that some inhibitors can increase the efficacy of therapeutic agents through synergistic effects, and suggest the possible targeting of both ABCG2 and ABCB1 transporters.
Article
Chemistry, Multidisciplinary
Kyzgaldak Ramazanova, Soumyadeep Chakrabortty, Bernd H. Mueller, Peter Loennecke, Johannes G. de Vries, Evamarie Hey-Hawkins
Summary: A convenient synthesis method for enantiopure mixed donor phosphine-phosphite ligands has been developed, incorporating P-stereogenic phosphanorbornane and axially chiral bisnaphthols into one ligand structure. These ligands exhibited excellent selectivity and moderate enantioselectivity in various catalyzed reactions.
Article
Chemistry, Inorganic & Nuclear
Zeno B. G. Fickenscher, Leexander Torres-Texeira, Peter Loennecke, Evamarie Hey-Hawkins
Summary: A heterobimetallic [Mo degrees;CoIII] complex and the monometallic [CoIII] counterpart were synthesized and characterized. Both metals are electronically independent from each other. The catalytic activity of [Mo degrees;CoIII] and [CoIII] in homogeneous carbon dioxide hydrogenation to formate was studied, with [Mo degrees;CoIII] showing very low activity and [CoIII] showing no conversion.
INORGANICA CHIMICA ACTA
(2023)
Article
Biochemistry & Molecular Biology
Aleksandr Kazimir, Benedikt Schwarze, Peter Loennecke, Sanja Jelaca, Sanja Mijatovic, Danijela Maksimovic-Ivanic, Evamarie Hey-Hawkins
Summary: This study evaluates the potential of a copper-tamoxifen hybrid complex as a therapeutic candidate for breast cancer. The results show that the complex exhibits remarkable activity against different types of breast cancer cell lines, highlighting its efficacy through diverse mechanisms of action.
RSC MEDICINAL CHEMISTRY
(2023)
