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Current Analytical Chemistry

Editor-in-Chief

ISSN (Print): 1573-4110
ISSN (Online): 1875-6727

HIGHLIGHTS

Can the Lewis Basicity of an Isolated Solvent Molecule be Used for Characterizing Solvent Effects?

Author(s): Jean-François Gal* and Pierre-Charles Maria

Volume 17, Issue 3, 2021

Published on: 07 June, 2020

Page: [328 - 338] Pages: 11

DOI: 10.2174/1573411016999200607171803

Price: $65

Open Access Journals Promotions 2
Abstract

Background: The ubiquitous Lewis acid/base interactions are important in solution processes. Analytical chemistry may benefit from a better understanding of the role of Lewis basicity at the molecular level or acting through a bulk solvent effect.

Objective: To delineate (i) the basicity at a molecular level, hereafter referred to as solute basicity, and (ii) the solvent basicity, which is a bulk-liquid property.

Methods: The literature that relates Lewis basicity scales and solvent effects is analyzed. A special focus is placed on two extensive scales, the Donor Number, DN, and the BF3 Affinity scale, BF3A, which were obtained by calorimetric measurements on molecules as solutes diluted in a quasi-inert solvent, and therefore define a molecular Lewis basicity. We discuss the validity of these solute scales when regarded as solvent scales, in particular when the basicity of strongly associated liquids is concerned.

Results: We demonstrate the drawbacks of confusing the Lewis basicity of a solvent molecule, isolated as a solute, and that of the bulk liquid solvent itself.

Conclusion: Consequently, we recommend a reasoned use of the concept of Lewis basicity taking clearly into account the specificity of the process for which a Lewis basicity effect may be invoked. In particular, the action of the Lewis base, either as an isolated entity or as a bulk liquid, must be distinguished.

Keywords: Donicity, donor number, lewis basicity, solute basicity, solvent basicity, solvent effects, trifluoroborane (boron trifluoride).

Graphical Abstract
[1]
Jensen, W.B. The Lewis Acid-Base Concepts: An Overview; Wiley: New York, 1980.
[2]
Finston, H.L.; Rychtman, A.C. New View of Current Acid–Base Theories; Wiley: New York, 1982.
[3]
Drago, R.S. Applications of electrostatic-covalent models in chemistry; Surfside: Gainesville, FL, 1994.
[4]
Gur’yanova, E.N.; Gol’dshtein, I.P.; Romm, I.P. Donor-Acceptor Bond; Wiley: New York, 1975.
[5]
Laurence, C.; Gal, J-F. Lewis Basicity and Affinity Scales: Data and Measurement; Wiley: New York, 2010.
[6]
Janzen, M.C.; Ponder, J.B.; Bailey, D.P.; Ingison, C.K.; Suslick, K.S. Colorimetric sensor arrays for volatile organic compounds. Anal. Chem., 2006, 78(11), 3591-3600.
[http://dx.doi.org/10.1021/ac052111s] [PMID: 16737212]
[7]
Lin, Y.; Smart, N.G.; Wai, C.M. Supercritical fluid extraction and chromatography of metal chelates and organometallic compounds. Trends Analyt. Chem., 1995, 14, 123-133.
[http://dx.doi.org/10.1016/0165-9936(95)94045-G]
[8]
Bowser, M.T.; Kranack, A.R.; Chen, D.D.Y. Analyte additive interactions in nonaqueous capillary electrophoresis: A critical review. Trends Analyt. Chem., 1998, 17, 424-434.
[http://dx.doi.org/10.1016/S0165-9936(98)00032-6]
[9]
Kalafut, P.; Kučera, R.; Klimeš, J. The retention behavior of acidic, basic and neutral pharmaceuticals on the deactivated polybutadiene zirconia phase. Curr. Anal. Chem., 2012, 8, 574-582.
[http://dx.doi.org/10.2174/157341112803216726]
[10]
Sakane, H. XAFS analysis applied to solutions. Anal. Sci., 2001, 17(Suppl.), i131-i134.
[11]
Barthel, J.; Gores, H-J. Solution Chemistry: A cutting edge in modern electrochemical technology. Chemistry of Nonaqueous Solutions-Current Progress; Mamantov, G; Popov, A.I., Ed.; Wiley-VCH: New York, Weinheim, 1994.
[12]
Nishi, N.; Murakami, H.; Imakura, S.; Kakiuchi, T. Facilitated transfer of alkali-metal cations by dibenzo-18-crown-6 across the electrochemically polarized interface between an aqueous solution and a hydrophobic room-temperature ionic liquid. Anal. Chem., 2006, 78(16), 5805-5812.
[http://dx.doi.org/10.1021/ac060797y] [PMID: 16906727]
[13]
Izutsu, K. Liquid junction potentials between electrolyte solutions in different solvents. Anal. Sci., 2011, 27(7), 685-694.
[http://dx.doi.org/10.2116/analsci.27.685] [PMID: 21747175]
[14]
Cowan, A.J.; Hardwick, L.J. Advanced spectroelectrochemical techniques to study electrode interfaces within lithium-ion and lithium-oxygen batteries. Annu. Rev. Anal. Chem. (Palo Alto, Calif.), 2019, 12(1), 323-346.
[http://dx.doi.org/10.1146/annurev-anchem-061318-115303] [PMID: 31038984]
[15]
Schumacher, P.D.; Doyle, J.L.; Schenk, J.O.; Clark, S.B. Electroanalytical chemistry of lanthanides and actinides. Rev. Anal. Chem., 2013, 32, 159-171.
[http://dx.doi.org/10.1515/revac-2012-0032]
[16]
Bhattacharyya, A.; Mohapatra, P.K. Separation of trivalent actinides and lanthanides using various ‘N’, ‘S’ and mixed ‘N,O’ donor ligands: A review. Radiochim. Acta, 2019, 107, 931-949.
[http://dx.doi.org/10.1515/ract-2018-3064]
[17]
Gutmann, V. Coordination Chemistry in Non-Aqueous Solutions; Springer-Verlag: Vienna, 1968.
[http://dx.doi.org/10.1007/978-3-7091-8194-2]
[18]
Gutmann, V. The Donor-Acceptor Approach to Molecular Interactions; Plenum Press: New York, 1978.
[http://dx.doi.org/10.1007/978-1-4615-8825-2]
[19]
Müller, P. Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994). Pure Appl. Chem., 1994, 66, 1077-1184. [Revision to be published
[http://dx.doi.org/10.1351/pac199466051077]
[20]
Gutmann, V.; Schmid, R. Empirical approach to ligand effects on the kinetics of substitution and redox reactions. Coord. Chem. Rev., 1974, 12, 263-293.
[http://dx.doi.org/10.1016/S0010-8545(00)82023-8]
[21]
Gutmann, V. Solvent effects on the reactivities of organometallic compounds. Coord. Chem. Rev., 1976, 18, 225-255.
[http://dx.doi.org/10.1016/S0010-8545(00)82045-7]
[22]
Gritzner, G.; Rechberger, P.; Gutmann, V. Solvent effects on the redox potential of cis-tetracarbonyl-bis-(1,3 dimethylimidazolidin-2-ylidene) chromium(0). J. Electroanal. Chem. Interfacial Electrochem., 1980, 114, 129-137.
[http://dx.doi.org/10.1016/S0022-0728(80)80440-2]
[23]
Gutmann, V.; Resch, G.; Linert, W. Structural variability in solutions. Coord. Chem. Rev., 1982, 43, 133-164.
[http://dx.doi.org/10.1016/S0010-8545(00)82094-9]
[24]
Maria, P-C.; Gal, J-F. A Lewis basicity scale for nonprotogenic solvents: Enthalpies of complex formation with boron trifluoride in dichloromethane. J. Phys. Chem., 1985, 89, 1296-1304.
[http://dx.doi.org/10.1021/j100253a048]
[25]
Maria, P-C.; Gal, J-F.; Elégant, L.; Azzaro, M. A microcalorimetric method for the measurement of the enthalpies of solution of gases in liquids. Thermochim. Acta, 1987, 115, 67-81.
[http://dx.doi.org/10.1016/0040-6031(87)88353-3]
[26]
Gal, J-F.; Maria, P-C.; Yáñez, M.; Mó, O. On the Lewis basicity of phosphoramides: A critical examination of their Donor Number through the comparison of enthalpies of adduct formation with SbCl5 and BF3. ChemPhysChem, 2019, 20(19), 2566-2576.
[http://dx.doi.org/10.1002/cphc.201900691] [PMID: 31449349]
[27]
Laurence, C.; Graton, J.; Gal, J-F. An overview of lewis basicity and affinity scales. J. Chem. Educ., 2011, 88, 1651-1657.
[http://dx.doi.org/10.1021/ed200057b]
[28]
Gal, J-F. Thermodynamic treatments of Lewis basicity in “Lewis base catalysis in organic chemistry”, Vedejs E; Denmark, S.E., Ed.; Wiley-VCH: Weinheim, 2016, Vol. 1, .
[29]
Zalewski, R.I.; Krygowski, T.M.; Shorter, J., Eds.; Similarity Models in Organic Chemistry, Biochemistry and Related Fields, Studies in Organic Chemistry; Elsevier: Amsterdam, New York, 1991, Vol. 42, .
[30]
Maria, P-C.; Gal, J-F.; de Franceschi, J.; Fargin, E. Chemometrics of the solvent basicity: Multivariate analysis of the basicity scales relevant to non-protogenic solvents. J. Am. Chem. Soc., 1987, 109, 483-492.
[http://dx.doi.org/10.1021/ja00236a029]
[31]
Pearson, R.G. Hard and soft acids and bases - The evolution of a chemical concept. Coord. Chem. Rev., 1990, 100, 403-425.
[http://dx.doi.org/10.1016/0010-8545(90)85016-L]
[32]
Pearson, R.G. The HSAB Principle - more quantitative aspects. Inorg. Chim. Acta, 1995, 240, 93-98.
[http://dx.doi.org/10.1016/0020-1693(95)04648-8]
[33]
Pearson, R.G. Chemical hardness and density functional theory. J. Chem. Sci., 2005, 117, 369-377.
[http://dx.doi.org/10.1007/BF02708340]
[34]
Drago, R.S.; Ferris, D.C.; Wong, N. A method for the analysis and prediction of gas-phase ion-molecule enthalpies. J. Am. Chem. Soc., 1990, 112, 8953-8961.
[http://dx.doi.org/10.1021/ja00180a047]
[35]
Drago, R.S.; Wong, N.M. The role of electron-density transfer and electronegativity in understanding chemical reactivity and bonding. J. Chem. Educ., 1996, 73, 123-129.
[http://dx.doi.org/10.1021/ed073p123]
[36]
Reichardt, C.; Welton, T. Solvents and Solvent Effects in Organic Chemistry, 4th ed; Wiley-VCH Weinheim, 2011.
[37]
Benoit, R.L.; Louis, C. Solvent Basicity. The Chemistry of Nonaqueous Solvents, Vol. VA; Lagowski, J.J., Ed.; Academic Press: New York, 1978.
[http://dx.doi.org/10.1016/B978-0-12-433805-0.50008-2]
[38]
For the definition of protogenic (non-protogenic) vs. protic (aprotic): Available from:, https://www.degruyter.com/view/journals/pac/66/5/article-p1077.xml
[http://dx.doi.org/10.1016/B978-0-12-433805-0.50008-2]
[39]
Abboud, J-L.M.; Notario, R. Critical compilation of scales of solvent parameters. Part I. Pure, non-hydrogen bond donor solvents (Technical Report). Pure Appl. Chem., 1999, 71, 645-718.
[http://dx.doi.org/10.1351/pac199971040645]
[40]
Marcus, Y. The effectivity of solvents as electron pair donors. J. Solution Chem., 1984, 13, 599-624.
[http://dx.doi.org/10.1007/BF00650369]
[41]
Marcus, Y. The properties of organic liquids that are relevant to their use as solvating solvents. Chem. Soc. Rev., 1993, 22, 409-416.
[http://dx.doi.org/10.1039/cs9932200409]
[42]
Marcus, Y. The Properties of Solvents; Wiley: Chichester, 1998.
[43]
Koppel, I.A.; Palm, V.A. The Influence of the Solvent on Organic Reactivity. Advances in Linear Free Energy Relationships; Chapman, N.B; Shorter, J., Ed.; Plenum Press: London, 1972.
[http://dx.doi.org/10.1007/978-1-4615-8660-9_5]
[44]
Derrieu, G. Étude de l'influence de l'environnement sur le groupement carbonyle, à partir de l'enthalpie de complexation par le trifluorure de bore (Study of the effect of the environment on the enthalpy of complexation by boron trifluoride). Thesis, Université de Nice,, 1973.
[45]
Gutmann, V.; Mayer, U. Donorstärken in 1,2-Dichloräthan, 3. Mitt. (Donor strengths in 1,2-dichloroethane. Part 3.). Monatsh. Chem., 1967, 98, 294-297.
[http://dx.doi.org/10.1007/BF00899944]
[46]
Olofsson, G. Enthalpy of adduct formation between antimony pentachloride and water. Acta Chem. Scand., 1967, 21, 1887-1891.
[http://dx.doi.org/10.3891/acta.chem.scand.21-1887]
[47]
Bernander, L.; Olofsson, G. A proton magnetic resonance study of SbCl5.H2O and SbCl5.2H2O adducts in solution. Acta Chem. Scand., 1973, 27, 1034-1037.
[http://dx.doi.org/10.3891/acta.chem.scand.27-1034]
[48]
Olofsson, G. Calorimetric studies of adduct formation between antimony pentachloride and methanol, methyl propyl ether, and dipropyl ether. Acta Chem. Scand., 1968, 22, 1352-1353.
[http://dx.doi.org/10.3891/acta.chem.scand.22-1352]
[49]
Mayer, U.; Gutmann, V. Phenomenological approach to cation-solvent interactions. Struct. Bonding, 1973, 12, 113-140.
[http://dx.doi.org/10.1007/BFb0117542]
[50]
Schmid, R. Re-interpretation of the solvent dielectric constant in coordination chemical terms. J. Solution Chem., 1983, 12, 135-152.
[http://dx.doi.org/10.1007/BF00645354]
[51]
Soukup, R.W.; Schmid, R. Metal Complexes as color lndicators for solvent parameters. J. Chem. Educ., 1985, 62, 459-462.
[http://dx.doi.org/10.1021/ed062p459]
[52]
Soukup, R.W.; Sone, K. (Acetylacetonato)(N,N,N′,N′-tertamethylethylenediamine) copper(II) Tetraphenylborate as a solvent basicity indicator. Bull. Chem. Soc. Jpn., 1987, 60, 2286-2299.
[http://dx.doi.org/10.1246/bcsj.60.2286]
[53]
Linert, W.; Taha, A. Spectroscopic, Thermodynamic and quantum mechanical studies on solvatochromic mixed ligand Copper(II)-Chelates. J. Coord. Chem., 1993, 29, 265-276.
[http://dx.doi.org/10.1080/00958979308045673]
[54]
Gritzner, B. A critical view on the Lewis-donor (nucleophilic) properties of solvents. J. Mol. Liq., 1997, 73-74, 487-500.
[http://dx.doi.org/10.1016/S0167-7322(97)00090-1]
[55]
Linert, W.; Fukuda, Y.; Camard, A. Chromotropism of coordination compounds and its applications in solution. Coord. Chem. Rev., 2001, 218, 113-152.
[http://dx.doi.org/10.1016/S0010-8545(01)80005-9]
[56]
Erlich, R.H.; Roach, E.; Popov, A.I. Solvation studies of sodium and lithium ions by Sodium-23 and Lithium-7 nuclear magnetic resonance. J. Am. Chem. Soc., 1970, 92, 4989-499.
[http://dx.doi.org/10.1021/ja00719a042]
[57]
Erlich, R.H.; Popov, A.I. Spectroscopic studies of ionic solvation. X. A Study of the solvation of sodium ions in nonaqueous solvents by 23Na nuclear magnetic resonance. J. Am. Chem. Soc., 1971, 93, 5620-5623.
[http://dx.doi.org/10.1021/ja00751a005]
[58]
Herlem, M.; Popov, A.I. Spectroscopic studies of ionic solvation. XI. Sodium magnetic resonance in basic solvents. J. Am. Chem. Soc., 1972, 94, 1431-1434.
[http://dx.doi.org/10.1021/ja00760a003]
[59]
Greenberg, M.S.; Bodner, R.L.; Alexander, A.I. Popov Spectroscopic Studies of Ionic Solvation. XIV. A Sodium-23 nuclear magnetic resonance and electrical conductance study of contact ion pairs in nonaqueous solvents. J. Phys. Chem., 1973, 77, 2449-2454.
[http://dx.doi.org/10.1021/j100639a018]
[60]
Gal, J-F.; Laurence, C. Comment on the article “Gutmann donor and acceptor numbers for ionic liquids” by M. Schmeisser, P. Illner, R. Puchta, A. Zahl, and R. van Eldik (Chem. Eur. J. 2012, 18, 10969-10982). Chemistry, 2013, 19(49), 16832-16834.
[http://dx.doi.org/10.1002/chem.201300147] [PMID: 24281817]
[61]
Schmeisser, M.; Illner, P.; Puchta, R.; Zahl, A.; van Eldik, R. Gutmann donor and acceptor numbers for ionic liquids. Chemistry, 2012, 18(35), 10969-10982.
[http://dx.doi.org/10.1002/chem.201200584] [PMID: 22806990]
[62]
Schmeisser, M.; Illner, P.; Puchta, R.; Zahl, A.; van Eldik, R. Reply to the comment on the article “Gutmann donor and acceptor numbers for ionic liquids” (Chem. Eur. J. 2012, 18, 10969-10982) by J.-F. Gal and C. Laurence. Chemistry, 2013, 19, 16835-16836.
[http://dx.doi.org/10.1002/chem.201302977] [PMID: 24203725]
[63]
Laszlo, P. Sodium-23 nuclear magnetic resonance spectroscopy. Angew. Chem. 1978, 90, 271-283. Angew. Chem. Int. Ed. Engl., 1978, 17, 254-266.
[http://dx.doi.org/10.1002/anie.197802541]
[64]
Holzweber, M.; Lungwitz, R.; Doerfler, D.; Spange, S.; Koel, M.; Hutter, H.; Linert, W. Mutual Lewis acid-base interactions of cations and anions in ionic liquids. Chemistry, 2013, 19(1), 288-293.
[http://dx.doi.org/10.1002/chem.201201978] [PMID: 23180598]
[65]
Linert, W.; Jameson, R.F.; Taha, A. Donor numbers of anions in solution: The use of solvatochromic lewis acid-base indicators. J. Chem. Soc., Dalton Trans., 1993, 3181-3186.
[http://dx.doi.org/10.1039/DT9930003181]
[66]
Linert, W.; Camard, A.; Armand, M.; Michot, C. Anions of low Lewis basicity for ionic solid state electrolytes. Coord. Chem. Rev., 2002, 226, 137-141.
[http://dx.doi.org/10.1016/S0010-8545(01)00416-7]
[67]
Corbett, P.J.; McIntosh, A.J.S.; Geeb, M.; Hallett, J.P. Use of ionic liquids to remove harmful M2+ contaminants from hydrocarbon streams. Mol. Syst. Des. Eng., 2018, 3, 408-417.
[http://dx.doi.org/10.1039/C7ME00111H]
[68]
Kuzmina, O.; Hassan, N.H.; Patel, L.; Ashworth, C.; Bakis, E.; White, A.J.P.; Hunt, P.A.; Welton, T. The impact of ionic liquids on the coordination of anions with solvatochromic copper complexes. Dalton Trans., 2017, 46(36), 12185-12200.
[http://dx.doi.org/10.1039/C7DT02372C] [PMID: 28872646]
[69]
Arnett, E.M.; Joris, L.; Mitchell, E.; Murty, T.S.S.R.; Gorrie, T.M.; Schleyer, P.R. Studies of hydrogen-bonded complex formation. III. Thermodynamics of complexing by infrared spectroscopy and calorimetry. J. Am. Chem. Soc., 1970, 92, 2365-2377.
[http://dx.doi.org/10.1021/ja00711a029]
[70]
Arnett, E.M.; Mitchell, E.J.; Murty, T.S.S.R. “Basicity.” A comparison of hydrogen bonding and proton transfer to some lewis base. J. Am. Chem. Soc., 1974, 96, 3875-3891.
[http://dx.doi.org/10.1021/ja00819a028]
[71]
Kamlet, M.J.; Abboud, J-L.M.; Taft, R.W. An examination of linear solvation energy relationships. Prog. Phys. Org. Chem., 1981, 13, 485-630.
[http://dx.doi.org/10.1002/9780470171929.ch6]
[72]
Kamlet, M.J.; Abboud, J-L.M.; Abraham, M.H.; Taft, R.W. Linear solvation energy relationships 23 A comprehensive collection of the solvatochromic parameters, π*, α and β, and some methods for simplifying the generalized solvatochromic equation. J. Org. Chem., 1983, 48, 2877-2887.
[http://dx.doi.org/10.1021/jo00165a018]
[73]
Abraham, M.H.; Buist, G.J.; Grellier, P.L.; McGill, R.A.; Prior, D.V.; Oliver, S.; Turner, E.; Morris, J.J.; Taylor, P.J.; Nicolet, P.; Maria, P-C.; Gal, J-F.; Abboud, J-L.M.; Doherty, R.M.; Kamlet, M.J.; Shuely, W.J.; Taft, R.W. Hydrogen-bonding 8. possible equivalence of solute and solvent scales of hydrogen- bond basicity of non-associated compounds. J. Phys. Org. Chem., 1989, 2, 540-552.
[http://dx.doi.org/10.1002/poc.610020706]
[74]
Abraham, M.H.; Duce, P.P.; Prior, D.V. hydrogen bonding. part 9. solute proton donor and proton acceptor scales for use in drug design. J. Chem. Soc., Perkin Trans. 2, 1989, 1355-1375.
[http://dx.doi.org/10.1039/p29890001355]
[75]
Catalán, J.; Gómez, J.; Couto, A.; Laynez, J. Toward a solvent basicity scale: The calorimetry of the pyrrole probe. J. Am. Chem. Soc., 1990, 112, 1678-1681.
[http://dx.doi.org/10.1021/ja00161a003]
[76]
Catalán, J.; Díaz, C.; López, V.; Pérez, P.; de Paz, J.L.G.; Rodríguez, J.G. A generalized solvent basicity scale: The solvatochromism of 5-Nitroindoline and its homomorph 1-Methyl-5-nitroindoline. Liebigs Ann., 1996, 1996, 1785-1794.
[http://dx.doi.org/10.1002/jlac.199619961112]
[77]
Catalán, J.; Palomar, J.; Díaz, C.; de Paz, J.L.G. On solvent basicity: Analysis of the SB scale. J. Phys. Chem. A, 1997, 101, 5183-5189.
[http://dx.doi.org/10.1021/jp970239a]
[78]
Cabot, R.; Hunter, C.A. Molecular probes of solvation phenomena. Chem. Soc. Rev., 2012, 41(9), 3485-3492.
[http://dx.doi.org/10.1039/c2cs15287h] [PMID: 22382921]
[79]
Laurence, C.; Legros, J.; Nicolet, P.; Vuluga, D.; Chantzis, A.; Jacquemin, D. Solvatomagnetic comparison method: A proper quantification of solvent hydrogen-bond basicity. J. Phys. Chem. B, 2014, 118(27), 7594-7608.
[http://dx.doi.org/10.1021/jp504630d] [PMID: 24919118]
[80]
Laurence, C.; Legros, J.; Chantzis, A.; Planchat, A.; Jacquemin, D. A database of dispersion-induction DI, electrostatic ES, and hydrogen bonding α1 and β1 solvent parameters and some applications to the multiparameter correlation analysis of solvent effects. J. Phys. Chem. B, 2015, 119(7), 3174-3184.
[http://dx.doi.org/10.1021/jp512372c] [PMID: 25629649]
[81]
Keserű, G.M.; Soós, T.; Kappe, C.O. Anthropogenic reaction parameters--the missing link between chemical intuition and the available chemical space. Chem. Soc. Rev., 2014, 43(15), 5387-5399.
[http://dx.doi.org/10.1039/C3CS60423C] [PMID: 24877159]
[82]
Coley, C.W.; Green, W.H.; Jensen, K.F. Machine learning in computer-aided synthesis planning. Acc. Chem. Res., 2018, 51(5), 1281-1289.
[http://dx.doi.org/10.1021/acs.accounts.8b00087] [PMID: 29715002]
[83]
Jia, X.; Lynch, A.; Huang, Y.; Danielson, M.; Lang’at, I.; Milder, A.; Ruby, A.E.; Wang, H.; Friedler, S.A.; Norquist, A.J.; Schrier, J. Anthropogenic biases in chemical reaction data hinder exploratory inorganic synthesis. Nature, 2019, 573(7773), 251-255.
[http://dx.doi.org/10.1038/s41586-019-1540-5] [PMID: 31511682]

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