{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T16:42:46Z","timestamp":1785256966520,"version":"3.55.0"},"reference-count":106,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2024,12,10]],"date-time":"2024-12-10T00:00:00Z","timestamp":1733788800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Education, Youth and Sports of the Czech Republic","award":["LM2023066"],"award-info":[{"award-number":["LM2023066"]}]},{"name":"Ministry of Education, Youth and Sports of the Czech Republic","award":["21-05926X"],"award-info":[{"award-number":["21-05926X"]}]},{"name":"Ministry of Education, Youth and Sports of the Czech Republic","award":["UJEP-SGS-2019-53-004-3"],"award-info":[{"award-number":["UJEP-SGS-2019-53-004-3"]}]},{"name":"Czech Science Foundation","award":["LM2023066"],"award-info":[{"award-number":["LM2023066"]}]},{"name":"Czech Science Foundation","award":["21-05926X"],"award-info":[{"award-number":["21-05926X"]}]},{"name":"Czech Science Foundation","award":["UJEP-SGS-2019-53-004-3"],"award-info":[{"award-number":["UJEP-SGS-2019-53-004-3"]}]},{"name":"UJEP\u2014Jan Evangelista Purkyn\u011b University in \u00dast\u00ed nad Labem","award":["LM2023066"],"award-info":[{"award-number":["LM2023066"]}]},{"name":"UJEP\u2014Jan Evangelista Purkyn\u011b University in \u00dast\u00ed nad Labem","award":["21-05926X"],"award-info":[{"award-number":["21-05926X"]}]},{"name":"UJEP\u2014Jan Evangelista Purkyn\u011b University in \u00dast\u00ed nad Labem","award":["UJEP-SGS-2019-53-004-3"],"award-info":[{"award-number":["UJEP-SGS-2019-53-004-3"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The most commonly used homogeneous catalyst for fatty acid esterification is a corrosive sulphuric acid. However, this requires costly investment in non-corrosive equipment, presents a safety risk, is time consuming, and increases effluent generation. In this study, inorganic 3D heteroborane cluster strong acids are employed for the first time as homogeneous catalysts. Three novel isomeric tetrachlorido and tetrabromido derivatives of 3,3\u2032-commo-bis[undecahydrido-closo-1,2-dicarba-3-cobaltadodecaborate](1\u2212) [1\u2212] were synthesised and fully characterised using a range of analytical techniques, including NMR, TLC, HPLC, MS, UV-Vis, melting point (MP), CHN analyses, and XRD. Ultimately, H3O[8,8\u2032-Cl2-1\u2212] was identified as the most efficient, reusable, and non-corrosive homogeneous catalyst for the esterification of four fatty acids. The reactions are conducted in an excess of alcohol at reflux. The effective absorption of water vapour provided by the molecular sieves maximises acid conversion. The hydrophobic dye Sudan black B was employed as an acid-base indicator to facilitate a comparison of the H0 acidity function of sulphuric acid and halogenated heteroboranoic acids when dissolved together in methanol. The 23Na NMR analysis demonstrated that the application of dry methanol resulted in the displacement of Na+ ions from zeolite, which subsequently exchanged the H3O+ ions of the acid. This process led to a gradual reduction in the efficiency of the catalysts, particularly with repeated use. The solution to this issue is to regenerate the catalyst on the ion exchanger following each reaction. In contrast to the published methods, our new approach meets 10 of 12 green chemistry principles.<\/jats:p>","DOI":"10.3390\/ijms252413263","type":"journal-article","created":{"date-parts":[[2024,12,10]],"date-time":"2024-12-10T11:17:20Z","timestamp":1733829440000},"page":"13263","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Halogenated Cobalt Bis-Dicarbollide Strong Acids as Reusable Homogeneous Catalysts for Fatty Acid Esterification with Methanol or Ethanol"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2041-4919","authenticated-orcid":false,"given":"Pavel","family":"Kaule","sequence":"first","affiliation":[{"name":"Department of Chemistry, Faculty of Science, Jan Evangelista Purkyn\u011b University in \u00dast\u00ed nad Labem, Pasteurova 3632\/15, 40096 \u00dast\u00ed nad Labem, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3163-1764","authenticated-orcid":false,"given":"V\u00e1clav","family":"\u0160\u00edcha","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Faculty of Science, Jan Evangelista Purkyn\u011b University in \u00dast\u00ed nad Labem, Pasteurova 3632\/15, 40096 \u00dast\u00ed nad Labem, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4723-0789","authenticated-orcid":false,"given":"Jan","family":"Mach\u00e1\u010dek","sequence":"additional","affiliation":[{"name":"Department of Syntheses, Institute of Inorganic Chemistry Czech Academy of Sciences, Hlavn\u00ed 1001, 25068 \u0158e\u017e, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-1032-1763","authenticated-orcid":false,"given":"Yelizaveta","family":"Naumkina","sequence":"additional","affiliation":[{"name":"Department of Solid State Chemistry, Faculty of Chemical Technology, University of Chemistry and Technology, Technick\u00e1 5, 16628 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5925-6217","authenticated-orcid":false,"given":"Jan","family":"\u010cejka","sequence":"additional","affiliation":[{"name":"Department of Solid State Chemistry, Faculty of Chemical Technology, University of Chemistry and Technology, Technick\u00e1 5, 16628 Prague, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6697","DOI":"10.1007\/s12649-019-00905-5","article-title":"Experimental Study on the Esterification of Fat Trap Grease in a Continuous Reactor","volume":"11","author":"Kadi","year":"2020","journal-title":"Waste Biomass Valor."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"10907","DOI":"10.1016\/j.biortech.2011.09.068","article-title":"Study of Biodiesel Production from Animal Fats with High Free Fatty Acid Content","volume":"102","author":"Encinar","year":"2011","journal-title":"Bioresour. Technol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"3566","DOI":"10.4028\/www.scientific.net\/AMR.518-523.3566","article-title":"Transesterification of Waste Cooking Oil to Produce Biodiesel Using Acid and Alkaline Catalyst","volume":"518\u2013523","author":"Li","year":"2012","journal-title":"AMR"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"012015","DOI":"10.1088\/1757-899X\/990\/1\/012015","article-title":"A Comparison of Palm Fatty Acid Distillate (PFAD) Esterification Using Sulphated Alumina versus Sulphuric Acid Catalyst","volume":"990","author":"Ulfah","year":"2020","journal-title":"IOP Conf. Ser. Mater. Sci. Eng."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"367","DOI":"10.1007\/s11746-003-0705-1","article-title":"Ethyl Esters from the Single-phase Base-catalyzed Ethanolysis of Vegetable Oils","volume":"80","author":"Zhou","year":"2003","journal-title":"J. Am. Oil Chem. Soc."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"e411","DOI":"10.1016\/j.ultras.2006.05.020","article-title":"Preparation of Biodiesel with the Help of Ultrasonic and Hydrodynamic Cavitation","volume":"44","author":"Ji","year":"2006","journal-title":"Ultrasonics"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"630","DOI":"10.1016\/j.wasman.2015.10.005","article-title":"Pilot-Scale Production of Biodiesel from Waste Fats and Oils Using Tetramethylammonium Hydroxide","volume":"48","author":"Pecha","year":"2016","journal-title":"Waste Manag."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1100\/2012\/475027","article-title":"Optimization of Sunflower Oil Transesterification Process Using Sodium Methoxide","volume":"2012","author":"KoohiKamali","year":"2012","journal-title":"Sci. World J."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"3252","DOI":"10.1002\/cber.189502803176","article-title":"Darstellung Der Ester","volume":"28","author":"Fischer","year":"1895","journal-title":"Ber. Dtsch. Chem. Ges."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"892","DOI":"10.1016\/j.biombioe.2008.01.001","article-title":"Esterification of Free Fatty Acids Using Sulfuric Acid as Catalyst in the Presence of Triglycerides","volume":"32","author":"Marchetti","year":"2008","journal-title":"Biomass Bioenergy"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"373","DOI":"10.1007\/s11746-000-0061-1","article-title":"Simple, High-efficiency Synthesis of Fatty Acid Methyl Esters from Soapstock","volume":"77","author":"Haas","year":"2000","journal-title":"J. Am. Oil Chem. Soc."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"267","DOI":"10.1016\/j.biombioe.2005.10.004","article-title":"Acid-Catalyzed Production of Biodiesel from Waste Frying Oil","volume":"30","author":"Zheng","year":"2006","journal-title":"Biomass Bioenergy"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"97","DOI":"10.1007\/s11746-003-0658-4","article-title":"Production of FAME from Acid Oil, a By-product of Vegetable Oil Refining","volume":"80","author":"Haas","year":"2003","journal-title":"J. Am. Oil Chem. Soc."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"2961","DOI":"10.1016\/j.fuel.2008.04.016","article-title":"Ataurrehman Biodiesel Production from Waste Tallow","volume":"87","author":"Bhatti","year":"2008","journal-title":"Fuel"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1087","DOI":"10.1016\/j.fuproc.2004.11.004","article-title":"Improving the Economics of Biodiesel Production through the Use of Low Value Lipids as Feedstocks: Vegetable Oil Soapstock","volume":"86","author":"Haas","year":"2005","journal-title":"Fuel Process. Technol."},{"key":"ref_16","unstructured":"Gunawardena, S., Walpita, D.H., and Ismail, M. (2017). Method for Quantification of Methanol and Sulfuric Acid Required for Esterification of High Free Fatty Acid Oils in Biodiesel Production. Int. J. Renew. Energy Res."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"20","DOI":"10.1007\/s10562-007-9318-z","article-title":"Acid-Catalyzed Homogeneous Esterification Reaction for Biodiesel Production from Palm Fatty Acids","volume":"122","author":"Aranda","year":"2008","journal-title":"Catal. Lett."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1005","DOI":"10.1016\/j.fuproc.2010.03.001","article-title":"Esterification with Ethanol to Produce Biodiesel from High Acidity Raw Materials","volume":"91","author":"Pisarello","year":"2010","journal-title":"Fuel Process. Technol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"6885","DOI":"10.1021\/ie800547h","article-title":"Biodiesel Production by Esterification of Oleic Acid with Methanol Using a Water Adsorption Apparatus","volume":"47","author":"Lucena","year":"2008","journal-title":"Ind. Eng. Chem. Res."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"902","DOI":"10.1016\/j.fuel.2010.10.022","article-title":"Oleic Acid Esterification with Ethanol under Continuous Water Removal Conditions","volume":"90","author":"Lucena","year":"2011","journal-title":"Fuel"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"689","DOI":"10.1080\/00986445.2017.1412312","article-title":"Effect of Alcohol Type and Amount on the Total Energy Consumption and Yield of the Free Fatty Acids Esterification Reaction with Simultaneous Adsorptive Water Removal","volume":"205","author":"Touma","year":"2018","journal-title":"Chem. Eng. Commun."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"2581","DOI":"10.1016\/j.renene.2010.03.035","article-title":"Biodiesel Production from Waste Coconut Oil by Esterification with Ethanol: The Effect of Water Removal by Adsorption","volume":"35","author":"Oliveira","year":"2010","journal-title":"Renew. Energy"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"014005","DOI":"10.1088\/2515-7655\/aca5b3","article-title":"State-of-the-Art Catalysts for Clean Fuel (Methyl Esters) Production\u2014a Comprehensive Review","volume":"5","author":"Jamil","year":"2023","journal-title":"J. Phys. Energy"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"80","DOI":"10.1016\/j.jiec.2021.07.018","article-title":"Current Developments in Esterification Reaction: A Review on Process and Parameters","volume":"103","author":"Khan","year":"2021","journal-title":"J. Ind. Eng. Chem."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Canakci, M., and Van Gerpen, J. (2001). Biodiesel Production from Oils and Fats with High Free Fatty Acids. Trans. ASAE, 44.","DOI":"10.13031\/2013.7010"},{"key":"ref_26","first-page":"257","article-title":"The Effect of Reactant Molar Ratio to Performance of H2SO4 Catalyst and para-Toluene Sulfonic Acid Catalyst in The Esterification of Palm Fatty Acid Distillate into Biodiesel","volume":"17","author":"Tambun","year":"2022","journal-title":"J. Eng. Sci. Technol."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"206","DOI":"10.3390\/suschem2010012","article-title":"Synthesis of Biodiesel from Tall Oil Fatty Acids by Homogeneous and Heterogeneous Catalysis","volume":"2","year":"2021","journal-title":"Sustain. Chem."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"388","DOI":"10.1007\/s40974-023-00283-8","article-title":"Optimized Recovery of Transesterifiable Oil from Industrial Fats, Oil, and Grease (FOG) Esterified with H2SO4 Catalyst Extracted from Discarded Lead-Acid Batteries","volume":"8","author":"Utlang","year":"2023","journal-title":"Energ. Ecol. Environ."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"780","DOI":"10.1016\/j.renene.2008.04.001","article-title":"Biodiesel Production by Esterification of Oleic Acid with Short-Chain Alcohols under Ultrasonic Irradiation Condition","volume":"34","author":"Hanh","year":"2009","journal-title":"Renew. Energy"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Somnuk, K., Phanyusoh, D., Thawornprasert, J., Oo, Y.M., and Prateepchaikul, G. (2021). Continuous Ultrasound-Assisted Esterification and Transesterification of Palm Fatty Acid Distillate for Ethyl Ester Production. Processes, 9.","DOI":"10.3390\/pr9030449"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"136","DOI":"10.1016\/j.pecs.2017.11.001","article-title":"Recent Advances in Sulfonated Resin Catalysts for Efficient Biodiesel and Bio-Derived Additives Production","volume":"65","author":"Trombettoni","year":"2018","journal-title":"Prog. Energy Combust. Sci."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"55","DOI":"10.1007\/s10563-014-9166-y","article-title":"Heterogeneous Solid Acid Catalysts for Esterification of Free Fatty Acids","volume":"18","author":"Lee","year":"2014","journal-title":"Catal. Surv. Asia"},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Rizwanul Fattah, I.M., Ong, H.C., Mahlia, T.M.I., Mofijur, M., Silitonga, A.S., Rahman, S.M.A., and Ahmad, A. (2020). State of the Art of Catalysts for Biodiesel Production. Front. Energy Res., 8.","DOI":"10.3389\/fenrg.2020.00101"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"2070","DOI":"10.1016\/j.rser.2012.01.003","article-title":"A Comprehensive Review on Biodiesel as an Alternative Energy Resource and Its Characteristics","volume":"16","author":"Atabani","year":"2012","journal-title":"Renew. Sustain. Energy Rev."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"131588","DOI":"10.1016\/j.jclepro.2022.131588","article-title":"A Review on Latest Trends in Cleaner Biodiesel Production: Role of Feedstock, Production Methods, and Catalysts","volume":"355","author":"Maheshwari","year":"2022","journal-title":"J. Clean. Prod."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"473","DOI":"10.1016\/j.rser.2016.04.011","article-title":"Application of Ionic Liquids and Deep Eutectic Solvents in Biodiesel Production: A Review","volume":"61","author":"Troter","year":"2016","journal-title":"Renew. Sustain. Energy Rev."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1225","DOI":"10.1016\/j.rser.2016.09.036","article-title":"A Review on Latest Developments and Future Prospects of Heterogeneous Catalyst in Biodiesel Production from Non-Edible Oils","volume":"67","author":"Mardhiah","year":"2017","journal-title":"Renew. Sustain. Energy Rev."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"380","DOI":"10.1016\/j.fuel.2018.10.030","article-title":"Application of Nanoparticles in Biofuels: An Overview","volume":"237","author":"Sekoai","year":"2019","journal-title":"Fuel"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"2721","DOI":"10.1021\/ja01346a015","article-title":"A Series of Simple Basic Indicators. I. The Acidity Functions of Mixtures of Sulfuric and Perchloric Acids with Water","volume":"54","author":"Hammett","year":"1932","journal-title":"J. Am. Chem. Soc."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"202","DOI":"10.1021\/ar50007a002","article-title":"Fluorosulfuric Acid and Related Superacid Media","volume":"1","author":"Gillespie","year":"1968","journal-title":"Acc. Chem. Res."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"6053","DOI":"10.1021\/ja00226a020","article-title":"Superacid Solutions in Hydrogen Fluoride","volume":"110","author":"Gillespie","year":"1988","journal-title":"J. Am. Chem. Soc."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"2161","DOI":"10.1039\/a700798a","article-title":"Acid Strength of Tetrafluoroboric Acid The Hydronium Ion as a Superacid and the Inapplicability of Water as an Indicator of Acid Strength","volume":"93","year":"1997","journal-title":"J. Chem. Soc. Faraday Trans."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"5352","DOI":"10.1002\/anie.200460005","article-title":"The Strongest Isolable Acid","volume":"43","author":"Juhasz","year":"2004","journal-title":"Angew Chem Int Ed"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"7258","DOI":"10.1039\/C4CC02816C","article-title":"A Quick, Simple, Robust Method to Measure the Acidity of Ionic Liquids","volume":"50","author":"Hallett","year":"2014","journal-title":"Chem. Commun."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"6885","DOI":"10.1002\/anie.201000252","article-title":"A Unified pH Scale for All Phases","volume":"49","author":"Himmel","year":"2010","journal-title":"Angew. Chem. Int. Ed."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"1622","DOI":"10.1002\/cphc.201100087","article-title":"Br\u00f8nsted Acidity and the Medium: Fundamentals with a Focus on Ionic Liquids","volume":"12","author":"Mihichuk","year":"2011","journal-title":"ChemPhysChem"},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"119637","DOI":"10.1016\/j.energy.2020.119637","article-title":"Synthesis of Generation-2 Polyamidoamine Based Ionic Liquid: Efficient Dendrimer Based Catalytic Green Fuel Production from Yellow Grease","volume":"219","author":"Panchal","year":"2021","journal-title":"Energy"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"1102","DOI":"10.1039\/c2cy20714a","article-title":"Biodiesel Synthesis from the Esterification of Free Fatty Acids and Alcohol Catalyzed by Long-Chain Br\u00f8nsted Acid Ionic Liquid","volume":"3","author":"He","year":"2013","journal-title":"Catal. Sci. Technol."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"5264","DOI":"10.1021\/ja0297382","article-title":"Determination of an Acidic Scale in Room Temperature Ionic Liquids","volume":"125","author":"Thomazeau","year":"2003","journal-title":"J. Am. Chem. Soc."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"101","DOI":"10.1126\/science.289.5476.101","article-title":"Taming Superacids: Stabilization of the Fullerene Cations HC60+ and C60+","volume":"289","author":"Reed","year":"2000","journal-title":"Science"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"1669","DOI":"10.1039\/B415425H","article-title":"Carborane Acids. New \u201cStrong yet Gentle\u201d Acids for Organic and Inorganic Chemistry","volume":"13","author":"Reed","year":"2005","journal-title":"Chem. Commun."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"1382","DOI":"10.1002\/anie.201509425","article-title":"The Strongest Acid: Protonation of Carbon Dioxide","volume":"55","author":"Cummings","year":"2016","journal-title":"Angew. Chem. Int. Ed."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"4516","DOI":"10.1002\/anie.201704645","article-title":"Features of Protonation of the Simplest Weakly Basic Molecules, SO2, CO, N2O, CO2, and Others by Solid Carborane Superacids","volume":"57","author":"Stoyanov","year":"2018","journal-title":"Angew. Chem. Int. Ed."},{"key":"ref_54","first-page":"443","article-title":"Carborane Analogues of Cobalticinium Ion","volume":"19","author":"Hawthorne","year":"1965","journal-title":"Chem. Commun."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"6700","DOI":"10.1039\/c4cc01283f","article-title":"Amphiphilic COSAN and I2-COSAN Crossing Synthetic Lipid Membranes: Planar Bilayers and Liposomes","volume":"50","author":"Alcaraz","year":"2014","journal-title":"Chem. Commun."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"927","DOI":"10.1021\/cr00019a005","article-title":"The Search for Larger and More Weakly Coordinating Anions","volume":"93","author":"Strauss","year":"1993","journal-title":"Chem. Rev."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1021\/ar970230r","article-title":"Carboranes: A New Class of Weakly Coordinating Anions for Strong Electrophiles, Oxidants, and Superacids","volume":"31","author":"Reed","year":"1998","journal-title":"Acc. Chem. Res."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"1907","DOI":"10.1021\/ja00084a034","article-title":"New Weakly Coordinating Anions. III. Useful Silver and Trityl Salt Reagents of Carborane Anions","volume":"116","author":"Xie","year":"1994","journal-title":"J. Am. Chem. Soc."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"2776","DOI":"10.1135\/cccc19842776","article-title":"Potential Uses of Metallocarborane Sandwich Anions for Analysis, Characterization and Isolation of Various Cations and Organic Bases","volume":"49","author":"Hanousek","year":"1984","journal-title":"Collect. Czech. Chem. Commun."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"349","DOI":"10.1007\/BF02060367","article-title":"Extraction of Cesium with Derivatives of Carborane into Nitrobenzene","volume":"148","author":"Rais","year":"1991","journal-title":"J. Radioanal. Nucl. Chem."},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"2893","DOI":"10.1016\/0277-5387(95)00200-C","article-title":"Caesium Cobalt Dicarbollide\u2014Solubility, Precipitation and Reactivity in Basic Aqueous Solution","volume":"14","author":"Fanning","year":"1995","journal-title":"Polyhedron"},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"4109","DOI":"10.1002\/chem.200401202","article-title":"Computational Study of Structures and Properties of Metallaboranes: Cobalt Bis(Dicarbollide)","volume":"11","author":"Hnyk","year":"2005","journal-title":"Chem. A Eur. J."},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"879","DOI":"10.1021\/ja01006a008","article-title":".pi.-Dicarbollyl Derivatives of the Transition Metals. Metallocene Analogs","volume":"90","author":"Hawthorne","year":"1968","journal-title":"J. Am. Chem. Soc."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"1376","DOI":"10.1016\/0022-1902(76)80156-X","article-title":"Extraction of Alkali Metals into Nitrobenzene in the Presence of Univalent Polyhedral Borate Anions","volume":"38","author":"Rais","year":"1976","journal-title":"J. Inorg. Nucl. Chem."},{"key":"ref_65","doi-asserted-by":"crossref","unstructured":"Sengupta, A.K., and Marcus, Y. (2004). Ion Exchange and Solvent Extraction: A Series of Advances, Marcel Dekker.","DOI":"10.1201\/9780203913604.bmatt"},{"key":"ref_66","doi-asserted-by":"crossref","first-page":"191","DOI":"10.1080\/01496398708068948","article-title":"Solvent Extraction Recovery of Byproduct 137Cs and 90Sr from HNO3 Solutions\u2014A Technology Review and Assessment","volume":"22","author":"Schulz","year":"1987","journal-title":"Sep. Sci. Technol."},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"511","DOI":"10.1016\/S0277-5387(00)81604-6","article-title":"B-Halogen Derivatives of the Bis(1,2-Dicarbollyl)Cobalt(III) Anion","volume":"1","author":"Rajec","year":"1982","journal-title":"Polyhedron"},{"key":"ref_68","doi-asserted-by":"crossref","first-page":"5215","DOI":"10.1021\/ic00125a021","article-title":"New Synthetic Routes to B-Halogenated Derivatives of Cobalt Dicarbollide","volume":"34","author":"Hurlburt","year":"1995","journal-title":"Inorg. Chem."},{"key":"ref_69","doi-asserted-by":"crossref","first-page":"2554","DOI":"10.1007\/s11172-005-0153-3","article-title":"Electrochemical Synthesis of Halogen Derivatives of Bis(1,2-Dicarbollyl)Cobalt(III)","volume":"53","author":"Rudakov","year":"2004","journal-title":"Russ. Chem. Bull."},{"key":"ref_70","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1016\/j.jorganchem.2013.03.039","article-title":"Preferential Chlorination Vertices in Cobaltabisdicarbollide Anions. Substitution Rate Correlation with Site Charges Computed by the Two Atoms Natural Population Analysis Method (2a-NPA)","volume":"747","author":"Teixidor","year":"2013","journal-title":"J. Organomet. Chem."},{"key":"ref_71","doi-asserted-by":"crossref","first-page":"144","DOI":"10.1016\/S0021-9673(00)88173-X","article-title":"Analysis of Boron\u2013Halogen Derivatives of Bis(1,2-Dicarbollyl)Cobalt(III) Anions by Capillary Isotachophoresis","volume":"243","author":"Koval","year":"1982","journal-title":"J. Chromatogr. A"},{"key":"ref_72","doi-asserted-by":"crossref","first-page":"121","DOI":"10.1016\/S0021-9673(01)94366-3","article-title":"Isotachophoretic Determination of Chloro Derivatives of Cobaltocarborane without the Use of Reference Analytes","volume":"390","author":"Kaniansky","year":"1987","journal-title":"J. Chromatogr. A"},{"key":"ref_73","doi-asserted-by":"crossref","first-page":"24","DOI":"10.1107\/S0108270186097445","article-title":"Structure of Caesium 3,3\u2019-Commo-Bis(8,9,12-Tribromooctahydro-1,2-Dicarba-3-Cobalta-Closo-Dodecaborate)(1-)","volume":"42","author":"Preisinger","year":"1986","journal-title":"Acta Crystallogr. C Cryst. Struct. Commun."},{"key":"ref_74","doi-asserted-by":"crossref","first-page":"2279","DOI":"10.1021\/ic50069a021","article-title":".pi.-Dicarbollyl Derivatives of Chromium. Metallocene Analogs","volume":"7","author":"Ruhle","year":"1968","journal-title":"Inorg. Chem."},{"key":"ref_75","doi-asserted-by":"crossref","first-page":"1137","DOI":"10.1007\/s11172-010-0216-y","article-title":"Synthesis, Structures, and Conductivities of Salts (BEDT-TTF)[9,9\u2032(12\u2032)-I2-3,3\u2032-Co(1,2-C2B9H10)2] and (TTF)[9,9\u2032,12,12\u2032-I4-3,3\u2032-Co(1,2-C2B9H9)2]","volume":"59","author":"Kazheva","year":"2010","journal-title":"Russ. Chem. Bull."},{"key":"ref_76","doi-asserted-by":"crossref","first-page":"712","DOI":"10.1007\/s11172-015-0924-4","article-title":"Synthesis of 9,9\u00b4,12,12\u00b4-Substituted Cobalt Bis(Dicarbollide) Derivatives","volume":"64","author":"Anufriev","year":"2015","journal-title":"Russ. Chem. Bull."},{"key":"ref_77","doi-asserted-by":"crossref","first-page":"17430","DOI":"10.1021\/acs.inorgchem.0c02719","article-title":"Tetrazole Ring Substitution at Carbon and Boron Sites of the Cobalt Bis(Dicarbollide) Ion Available via Dipolar Cycloadditions","volume":"59","author":"Bavol","year":"2020","journal-title":"Inorg. Chem."},{"key":"ref_78","doi-asserted-by":"crossref","first-page":"809","DOI":"10.1021\/ic960811x","article-title":"Butyllithium Deprotonation vs Alkali Metal Reduction of Cobalt Dicarbollide: A New Synthetic Route to C-Substituted Derivatives","volume":"36","author":"Chamberlin","year":"1997","journal-title":"Inorg. Chem."},{"key":"ref_79","doi-asserted-by":"crossref","first-page":"4604","DOI":"10.1021\/ic961182u","article-title":"Condensation Polymerization of Cobalt Dicarbollide Dicarboxylic Acid","volume":"36","author":"Fino","year":"1997","journal-title":"Inorg. Chem."},{"key":"ref_80","doi-asserted-by":"crossref","first-page":"7498","DOI":"10.1039\/c2dt30128h","article-title":"Direct and Facile Synthesis of Carbon Substituted Alkylhydroxy Derivatives of Cobalt Bis(1,2-Dicarbollide), Versatile Building Blocks for Synthetic Purposes","volume":"41","year":"2012","journal-title":"Dalton Trans."},{"key":"ref_81","doi-asserted-by":"crossref","first-page":"5106","DOI":"10.1039\/c3dt52870g","article-title":"Synthesis, Characterisation and Some Chemistry of C- and B-Substituted Carboxylic Acids of Cobalt Bis(Dicarbollide)","volume":"43","author":"Nekvinda","year":"2014","journal-title":"Dalton Trans."},{"key":"ref_82","doi-asserted-by":"crossref","first-page":"2887","DOI":"10.1039\/C9RA08551C","article-title":"Synthesis and Study of C -Substituted Methylthio Derivatives of Cobalt Bis(Dicarbollide)","volume":"10","author":"Stogniy","year":"2020","journal-title":"RSC Adv."},{"key":"ref_83","doi-asserted-by":"crossref","first-page":"1413","DOI":"10.1021\/om00039a058","article-title":"Metallacarboranes as Labile Anions for Ionic Zirconocene Olefin Polymerization Catalysts","volume":"11","author":"Hlatky","year":"1992","journal-title":"Organometallics"},{"key":"ref_84","doi-asserted-by":"crossref","first-page":"6898","DOI":"10.1021\/jo00102a009","article-title":"Lithium Cobalt-Bis-Dicarbollide: A Novel Lewis Acid Catalyst for the Conjugate Addition of Silyl Ketene Acetals to Hindered.alpha.,.beta.-Unsaturated Carbonyl Compounds","volume":"59","author":"DuBay","year":"1994","journal-title":"J. Org. Chem."},{"key":"ref_85","doi-asserted-by":"crossref","first-page":"8707","DOI":"10.1016\/S0040-4039(96)02021-7","article-title":"Lithium Cobalt-Bis-Dicarbollide Catalyzed Substitution Reactions of Allylic Acetates","volume":"37","author":"Grieco","year":"1996","journal-title":"Tetrahedron Letters"},{"key":"ref_86","doi-asserted-by":"crossref","first-page":"458","DOI":"10.1134\/S1990793109030208","article-title":"Catalytic Effect of Bis(Carbollyl) Complexes of Metals on the Combustion of Condensed Systems","volume":"3","author":"Nechai","year":"2009","journal-title":"Russ. J. Phys. Chem. B"},{"key":"ref_87","doi-asserted-by":"crossref","first-page":"67","DOI":"10.1002\/open.201100014","article-title":"An Efficient and Recyclable Catalytic System Comprising Nanopalladium(0) and a Pyridinium Salt of Iron Bis(Dicarbollide) for Oxidation of Substituted Benzyl Alcohol and Lignin","volume":"1","author":"Zhu","year":"2012","journal-title":"ChemistryOpen"},{"key":"ref_88","doi-asserted-by":"crossref","first-page":"195","DOI":"10.1016\/j.jorganchem.2017.05.040","article-title":"Ionic Composite of Palladium(II)\/Iron Bis(Dicarbollide) for Catalytic Oxidative Carbonylation in the Formation of Diphenyl Carbonate","volume":"849\u2013850","author":"Biying","year":"2017","journal-title":"J. Organomet. Chem."},{"key":"ref_89","doi-asserted-by":"crossref","first-page":"3878","DOI":"10.1002\/ejic.201800649","article-title":"Low-Symmetry Phthalocyanine Cobalt Bis(Dicarbollide) Conjugate for Hydrogen Reduction","volume":"2018","author":"Nar","year":"2018","journal-title":"Eur. J. Inorg. Chem."},{"key":"ref_90","doi-asserted-by":"crossref","first-page":"5027","DOI":"10.1002\/chem.201905395","article-title":"Metallacarboranes as Photoredox Catalysts in Water","volume":"26","author":"Guerrero","year":"2020","journal-title":"Chem. A Eur. J."},{"key":"ref_91","doi-asserted-by":"crossref","first-page":"56372","DOI":"10.1021\/acsami.0c17847","article-title":"Noncovalently Linked Metallacarboranes on Functionalized Magnetic Nanoparticles as Highly Efficient, Robust, and Reusable Photocatalysts in Aqueous Medium","volume":"12","author":"Guerrero","year":"2020","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_92","doi-asserted-by":"crossref","first-page":"10123","DOI":"10.1039\/D1GC03119H","article-title":"A Stand-Alone Cobalt Bis(Dicarbollide) Photoredox Catalyst Epoxidates Alkenes in Water at Extremely Low Catalyst Load","volume":"23","author":"Guerrero","year":"2021","journal-title":"Green Chem."},{"key":"ref_93","doi-asserted-by":"crossref","first-page":"447","DOI":"10.1016\/S0022-328X(00)83259-3","article-title":"The Analysis of Organolithium Compounds","volume":"2","author":"Gilman","year":"1964","journal-title":"J. Organomet. Chem."},{"key":"ref_94","doi-asserted-by":"crossref","first-page":"325","DOI":"10.1021\/cr00010a007","article-title":"Boron-11 NMR Spectra of Boranes, Main-Group Heteroboranes, and Substituted Derivatives. Factors Influencing Chemical Shifts of Skeletal Atoms","volume":"92","year":"1992","journal-title":"Chem. Rev."},{"key":"ref_95","doi-asserted-by":"crossref","first-page":"20","DOI":"10.1016\/S0020-1693(99)00055-9","article-title":"NMR as a Tool for Elucidation of Structures and Estimation of Electron Distribution in Boranes and Their Derivatives","volume":"289","year":"1999","journal-title":"Inorganica Chim. Acta"},{"key":"ref_96","doi-asserted-by":"crossref","first-page":"237","DOI":"10.1007\/BF00492246","article-title":"Sudan Black B: Chemical Structure and Histochemistry of the Blue Main Components","volume":"54","author":"Franz","year":"1977","journal-title":"Histochemistry"},{"key":"ref_97","doi-asserted-by":"crossref","first-page":"155","DOI":"10.3109\/10520295809111840","article-title":"Decomposition of Sudan Black B Causing an Artefact in the Staining of Lipids","volume":"33","author":"Fredricsson","year":"1958","journal-title":"Stain. Technol."},{"key":"ref_98","doi-asserted-by":"crossref","first-page":"68","DOI":"10.1007\/BF00306212","article-title":"Thin Layer Chrornatography and Histochemistry of Sudan Black B","volume":"16","author":"Lansink","year":"1968","journal-title":"Histochemie"},{"key":"ref_99","doi-asserted-by":"crossref","first-page":"497","DOI":"10.1016\/S0021-9673(97)00497-4","article-title":"High-Performance Liquid Chromatographic Separations of Boron-Cluster Compounds","volume":"789","year":"1997","journal-title":"J. Chromatogr. A"},{"key":"ref_100","unstructured":"(2024, December 06). XcaliburTM. Available online: https:\/\/www.thermofisher.com\/order\/catalog\/product\/OPTON-30965?SID=srch-srp-OPTON-30965."},{"key":"ref_101","unstructured":"(2018). APEX3, SAINT and SADABS, Bruker AXS Inc."},{"key":"ref_102","doi-asserted-by":"crossref","first-page":"786","DOI":"10.1107\/S0021889807029238","article-title":"SUPERFLIP\u2014A Computer Program for the Solution of Crystal Structures by Charge Flipping in Arbitrary Dimensions","volume":"40","author":"Palatinus","year":"2007","journal-title":"J. Appl. Crystallogr."},{"key":"ref_103","doi-asserted-by":"crossref","first-page":"1487","DOI":"10.1107\/S0021889803021800","article-title":"CRYSTALS Version 12: Software for Guided Crystal Structure Analysis","volume":"36","author":"Betteridge","year":"2003","journal-title":"J. Appl. Crystallogr."},{"key":"ref_104","doi-asserted-by":"crossref","first-page":"600","DOI":"10.1107\/S0021889807018894","article-title":"MCE2005\u2014A New Version of a Program for Fast Interactive Visualization of Electron and Similar Density Maps Optimized for Small Molecules","volume":"40","year":"2007","journal-title":"J. Appl. Crystallogr."},{"key":"ref_105","unstructured":"(2024, December 06). Delta NMR Software. Available online: https:\/\/www.jeol.com\/products\/scientific\/nmr_software\/Delta5.php."},{"key":"ref_106","unstructured":"(2024, December 06). Eager SmartTM. Available online: https:\/\/www.thermofisher.com\/order\/catalog\/product\/11206100."}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/25\/24\/13263\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T16:51:45Z","timestamp":1760115105000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/25\/24\/13263"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,12,10]]},"references-count":106,"journal-issue":{"issue":"24","published-online":{"date-parts":[[2024,12]]}},"alternative-id":["ijms252413263"],"URL":"https:\/\/doi.org\/10.3390\/ijms252413263","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,12,10]]}}}