Relationships between aqueous acidities and computed surface-electrostatic potentials and local ionization energies of substituted phenols and benzoic acids
Tóm tắt
Electrostatic potentials and average local ionization energies on the molecular surfaces of 19 phenols, 17 benzoic acids and their respective conjugate bases were computed at the HF/STO-5G(d)//B3LYP/6-311G(d,p) level. Good correlations were found between pK as and the V S,max values of the neutral acids and the V S,min and % MathType!Translator!2!1!AMS LaTeX.tdl!TeX -- AMS-LaTeX! % MathType!MTEF!2!1!+- % feaafeart1ev1aaatCvAUfeBSn0BKvguHDwzZbqefeKCPfgBGuLBPn % 2BKvginnfarmWu51MyVXgatuuDJXwAK1uy0HwmaeHbfv3ySLgzG0uy % 0Hgip5wzaebbnrfifHhDYfgasaacH8YjY-vipgYlH8Gipec8Eeeu0x % Xdbba9frFj0-OqFfea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs % 0dXdbPYxe9vr0-vr0-vqpWqaaeaabiGaciaacaqabeaadaqadqaaaO % qaaiqadMeagaqeamaaBaaaleaacaqGtbGaaeilaiaab2gacaqGPbGa % aeOBaaqabaaaaa!3D93! $$ \bar{I}_{{{\text{S,min}}}} $$ of the conjugate bases for both sets of molecules. V S,max is the most positive value of the electrostatic potential on the molecular surface and is an indicator of the ease with which the phenols and benzoic acids lose their acidic hydrogens. V S,min and % MathType!Translator!2!1!AMS LaTeX.tdl!TeX -- AMS-LaTeX! <![CDATA[% MathType!MTEF!2!1!+- % feaafeart1ev1aaatCvAUfeBSn0BKvguHDwzZbqefeKCPfgBGuLBPn % 2BKvginnfarmWu51MyVXgatuuDJXwAK1uy0HwmaeHbfv3ySLgzG0uy % 0Hgip5wzaebbnrfifHhDYfgasaacH8YjY-vipgYlH8Gipec8Eeeu0x % Xdbba9frFj0-OqFfea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs % 0dXdbPYxe9vr0-vr0-vqpWqaaeaabiGaciaacaqabeaadaqadqaaaO % qaaiqadMeagaqeamaaBaaaleaacaqGtbGaaeilaiaab2gacaqGPbGa % aeOBaaqabaaaaa!3D93! $$ \bar{I}_{{{\text{S,min}}}} $$ are the minimum values of the electrostatic potential and the local ionization energy computed on the molecular surface; the V S,min and % MathType!Translator!2!1!AMS LaTeX.tdl!TeX -- AMS-LaTeX! <![CDATA[% MathType!MTEF!2!1!+- % feaafeart1ev1aaatCvAUfeBSn0BKvguHDwzZbqefeKCPfgBGuLBPn % 2BKvginnfarmWu51MyVXgatuuDJXwAK1uy0HwmaeHbfv3ySLgzG0uy % 0Hgip5wzaebbnrfifHhDYfgasaacH8YjY-vipgYlH8Gipec8Eeeu0x % Xdbba9frFj0-OqFfea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs % 0dXdbPYxe9vr0-vr0-vqpWqaaeaabiGaciaacaqabeaadaqadqaaaO % qaaiqadMeagaqeamaaBaaaleaacaqGtbGaaeilaiaab2gacaqGPbGa % aeOBaaqabaaaaa!3D93! $$ \bar{I}_{{{\text{S,min}}}} $$ of the conjugate bases of the phenoxides and benzoates are indicative, respectively, of the tendencies of electrophiles to approach the anions (V S,min) and to react with the anions ( % MathType!Translator!2!1!AMS LaTeX.tdl!TeX -- AMS-LaTeX! <![CDATA[% MathType!MTEF!2!1!+- % feaafeart1ev1aaatCvAUfeBSn0BKvguHDwzZbqefeKCPfgBGuLBPn % 2BKvginnfarmWu51MyVXgatuuDJXwAK1uy0HwmaeHbfv3ySLgzG0uy % 0Hgip5wzaebbnrfifHhDYfgasaacH8YjY-vipgYlH8Gipec8Eeeu0x % Xdbba9frFj0-OqFfea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs % 0dXdbPYxe9vr0-vr0-vqpWqaaeaabiGaciaacaqabeaadaqadqaaaO % qaaiqadMeagaqeamaaBaaaleaacaqGtbGaaeilaiaab2gacaqGPbGa % aeOBaaqabaaaaa!3D93! $$ \bar{I}_{{{\text{S,min}}}} $$ ) to reform the original acids. The correlations observed between the computed molecular surface quantities, taken as single parameters, and the experimental pK a values ranged from R=0.938 to R=0.970 for the two classes of compounds. Figure Correlation between pK a and the computed V S,max of the benzoic acids listed in Table 2. The linear correlation coefficient is 0.970
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citation_journal_title=Can J Chem; citation_author=null Haeberlein; citation_volume=70; citation_publication_date=1992; citation_pages=2209; citation_id=CR1
citation_journal_title=Int J Quantum Chem; citation_author=null Gross; citation_volume=80; citation_publication_date=2000; citation_pages=1107; citation_doi=10.1002/1097-461X(2000)80:4/5<1107::AID-QUA60>3.3.CO;2-K; citation_id=CR2
citation_journal_title=J Org Chem; citation_author=null Gross; citation_volume=66; citation_publication_date=2001; citation_pages=6919; citation_doi=10.1021/jo010234g; citation_id=CR3
citation_journal_title=Int J Quantum Chem; citation_author=null Gross; citation_volume=85; citation_publication_date=2001; citation_pages=569; citation_doi=10.1002/qua.1525; citation_id=CR4
citation_journal_title=Int J Quantum Chem; citation_author=null Hollingsworth; citation_volume=90; citation_publication_date=2002; citation_pages=1396; citation_doi=10.1002/qua.10362; citation_id=CR5
Murray JS, Politzer P (1998) Average local ionization energies: significance and applications. In: Parkanyi C (ed) Theoretical organic chemistry. Elsevier, Amsterdam, chapter 7
Politzer P, Daiker KC (1981) In: Deb BM (ed) The force concept in chemistry. Van Nostrand Reinhold, New York, pp 294–387
Politzer P, Murray JS (1991) In: Lipkowitz KB, Boyd DB (eds) Reviews in computational chemistry II. VCH, New York, chapter 7
Murray JS, Politzer P (1998) Molecular electrostatic potentials. In: Schleyer PvR (ed) Encyclopedia of computational chemistry. Wiley, New York
Murray JS, Politzer P (1992) J Chem Res (S) 110–111
citation_journal_title=J Mol Struct (Theochem); citation_author=JS Murray, T Brinck, ME Grice, P Politzer; citation_volume=256; citation_publication_date=1992; citation_pages=29-45; citation_id=CR11
citation_journal_title=Can J Chem; citation_author=null Sjoberg; citation_volume=68; citation_publication_date=1990; citation_pages=1440; citation_id=CR12
citation_journal_title=Physica; citation_author=null Koopmans; citation_volume=1; citation_publication_date=1933; citation_pages=104; citation_id=CR13
citation_journal_title=J Org Chem; citation_author=null Brinck; citation_volume=56; citation_publication_date=1991; citation_pages=5012; citation_id=CR14
citation_journal_title=J Org Chem; citation_author=null Brinck; citation_volume=56; citation_publication_date=1991; citation_pages=2934; citation_id=CR15
citation_journal_title=Int J Quantum Chem, Quantum Chem Symp; citation_author=JS Murray, JM Seminario, P Politzer, P Sjoberg; citation_volume=24; citation_publication_date=1990; citation_pages=645-653; citation_id=CR16
citation_journal_title=Int J Quantum Chem; citation_author=null Brinck; citation_volume=48; citation_publication_date=1993; citation_pages=73; citation_id=CR17
Murray JS, Abu-Awwad F, Politzer P (2000) J Mol Struct (Theochem) 501–502:241–250
citation_journal_title=Int J Quantum Chem; citation_author=null Politzer; citation_volume=88; citation_publication_date=2002; citation_pages=19; citation_doi=10.1002/qua.10109; citation_id=CR19
citation_journal_title=Int J Quantum Chem; citation_author=null Jin; citation_volume=96; citation_publication_date=2004; citation_pages=394; citation_doi=10.1002/qua.10717; citation_id=CR20
Scrocco E, Tomasi J (1973) In: Topics in current chemistry. Springer, Berlin Heidelberg New York, pp 95-170
Politzer P, Truhlar DG (eds) (1981) Chemical applications of atomic and molecular electrostatic potentials. Plenum, New York
Naray-Szabo G, Ferenczy GG (1995) Chem Rev 95, pp 829–847
Murray JS, Sen K (eds) (1996) Molecular electrostatic potentials. Elsevier, Amsterdam
citation_journal_title=Can J Chem; citation_author=null Hagelin; citation_volume=73; citation_publication_date=1995; citation_pages=483; citation_id=CR25
citation_journal_title=J Chem Phys; citation_author=null Pathak; citation_volume=93; citation_publication_date=1990; citation_pages=1770; citation_doi=10.1063/1.459703; citation_id=CR26
SAS. SAS Institute Inc, Cary, NC, 27511
Albert A, Serjeant EF (1962) Ionization constants of acids and bases. Methuen, London
citation_journal_title=Int J Quantum Chem: Biophys Q; citation_author=JS Murray, Z Peralta-Inga, P Politzer, K Ekanayake, P LeBreton; citation_volume=83; citation_publication_date=2001; citation_pages=245-254; citation_id=CR29
citation_journal_title=Int J Quantum Chem; citation_author=null Murray; citation_volume=75; citation_publication_date=1999; citation_pages=267; citation_doi=10.1002/(SICI)1097-461X(1999)75:3<267::AID-QUA16>3.3.CO;2-E; citation_id=CR30
citation_journal_title=Int J Quantum Chem; citation_author=null Hussein; citation_volume=82; citation_publication_date=2001; citation_pages=160; citation_doi=10.1002/qua.1031; citation_id=CR31