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Perrin CL. Symmetry of Hydrogen Bonds: Application of NMR Method of Isotopic Perturbation and Relevance of Solvatomers. Molecules 2023; 28:molecules28114462. [PMID: 37298938 DOI: 10.3390/molecules28114462] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 05/25/2023] [Accepted: 05/27/2023] [Indexed: 06/12/2023] Open
Abstract
Short, strong, symmetric, low-barrier hydrogen bonds (H-bonds) are thought to be of special significance. We have been searching for symmetric H-bonds by using the NMR technique of isotopic perturbation. Various dicarboxylate monoanions, aldehyde enols, diamines, enamines, acid-base complexes, and two sterically encumbered enols have been investigated. Among all of these, we have found only one example of a symmetric H-bond, in nitromalonamide enol, and all of the others are equilibrating mixtures of tautomers. The nearly universal lack of symmetry is attributed to the presence of these H-bonded species as a mixture of solvatomers, meaning isomers (or stereoisomers or tautomers) that differ in their solvation environment. The disorder of solvation renders the two donor atoms instantaneously inequivalent, whereupon the hydrogen attaches to the less well solvated donor. We therefore conclude that there is no special significance to short, strong, symmetric, low-barrier H-bonds. Moreover, they have no heightened stability or else they would have been more prevalent.
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Affiliation(s)
- Charles L Perrin
- Department of Chemistry & Biochemistry University of California, La Jolla, San Diego, CA 92093, USA
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2
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Wang T, Xu ES, Chen B, Hoffmann R, Crespi VH. Theory of Borazine-Derived Nanothreads: Enumeration, Reaction Pathways, and Piezoelectricity. ACS NANO 2022; 16:15884-15893. [PMID: 36166474 DOI: 10.1021/acsnano.2c02778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Nanothreads are one-dimensional macromolecules formed by pressure-induced polymerization along stacks of multiply unsaturated (or highly strained) molecules such as benzene (or cubane). Borazine is isoelectronic to benzene yet with substantial bond polarity, thus motivating a theoretical examination of borazine-derived nanothreads with degrees of saturation of 2, 4, and 6 (defined as the number of four-coordinated boron and nitrogen atoms per borazine formula unit). The energy increases upon going from molecular borazine to degree-2 borazine-derived threads and then decreases for degree-4 and degree-6 nanothreads as more σ bonds are formed. With the constraint of no more than two borazine formula units within the repeat unit of the framework's bonding topology, there are only 13 fully saturated (i.e., degree-6) borazine-derived nanothreads that avoid energetically costly homopolar bonds (as compared to more than 50 such candidates for benzene-derived threads). Only two of these are more stable than borazine. Hypothetical pathways from molecular borazine to these two degree-6 borazine-derived nanothreads are discussed. This relative paucity of outcomes may assist in kinetic control of reaction products. Beyond the high mechanical strength also predicted for carbon-based threads, properties such as piezoelectricity and flexoelectricity may be accessible to the polar lattice of borazine-derived nanothreads, with intriguing prospects for expression in these extremely thin yet rigid objects.
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Affiliation(s)
- Tao Wang
- Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - En-Shi Xu
- Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- School of Physics and Electronics, Qiannan Normal University for Nationalities, Duyun 558000, P.R. China
| | - Bo Chen
- Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 Donostia-San Sebastian, Spain
- IKERBASQUE, Basque Foundation for Science, Plaza Euskadi 5, 48009 Bilbao, Spain
| | - Roald Hoffmann
- Department of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, Ithaca, New York 14853-1301, United States
| | - Vincent H Crespi
- Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Department of Materials Science and Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States
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3
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Ozeryanskii VA, Kolupaeva EV, Pozharskii AF. N-Methylated 1,8-Diaminonaphthalenes as Bifunctional Nucleophiles in Reactions with α,ω-Dihalogenoalkanes: A Facile Route to Heterocyclic and Double Proton Sponges. SYNTHESIS-STUTTGART 2020. [DOI: 10.1055/s-0040-1707079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The reaction of 1-dimethylamino-8-(methylamino)naphthalene with 1,3-dibromopropane chemoselectively leads to the product of N,N′-heterocyclization, while in the case of 1,4-dibromobutane and 1,2-bis(bromomethyl)benzene the process results in heterocyclization onto the same nitrogen atom with the formation of previously unknown 1-dimethylamino-8-pyrrolidino- and 1-dimethylamino-8-isoindolino-naphthalenes. The same reactions conducted without adding any auxiliary base lead to the formation of N,N′-linked double proton sponges as a new type of polynitrogen organic receptor. Proceeding as a sequence of quaternization–demethylation–cyclization steps, this heterocyclization process can also be used to construct six-membered rings (piperidino, morpholino), albeit in lower yields. The ability of 1,2-dibromoethane to brominate N-alkylated 1,8-diaminonaphthalenes is also described. It is shown for the first time that a commercially available 1,8-bis(dimethylamino)naphthalene (DMAN) can be used as a starting material in a heterocyclization reaction, which via a one-pot approach and in a short time can be converted into 1,5-dimethylnaphtho[1,8-bc]-1,5-diazacyclooctane or 1-dimethylamino-8-(pyrrolidin-1-yl)naphthalene.
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Synthesis of 2‐Aryl‐ and 2,7‐Diaryl‐1,8‐bis(dimethylamino)naphthalenes. Overview of the “Buttressing effect” in 2,7‐Disubstituted Proton Sponges. ChemistrySelect 2020. [DOI: 10.1002/slct.202002745] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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5
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Pozharskii AF, Ozeryanskii VA, Filatova EA, Dyablo OV, Pogosova OG, Borodkin GS, Filarowski A, Steglenko DV. Neutral Pyrrole Nitrogen Atom as a π- and Mixed n,π-Donor in Hydrogen Bonding. J Org Chem 2019; 84:726-737. [PMID: 30576143 DOI: 10.1021/acs.joc.8b02562] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
9-Dimethylaminobenzo[ g]indoles 3-6 and 1-dimethylamino-8-(pyrrolyl-1)naphthalene 7 were examined as possible models for establishing the ability of the pyrrole nitrogen atom to participate in [NHN]+ hydrogen bonding as a proton acceptor. Indoles 3-5 (to a lesser extent 6) form rather stable tetrafluoroborates, with the proton mostly located on the NMe2 group but simultaneously engaged in the formation of a charged intramolecular [NHN]+ hydrogen bond (IHB) with the pyrrole N atom. The theoretically estimated energies of IHB in salts 3H+BF4--6H+BF4- vary between 7.0-10.7 and 6.2-7.0 kcal mol-1 in vapor and MeCN, respectively. The pyrrole N atom undergoes a perceptible pyramidalization but still remains involved in the 6π-electron aromatic system, suggesting that the hydrogen bonding in salts 3H+BF4--6H+BF4- represents a previously unknown mixed NH···N(n,π) interaction. Despite the favorable orientation of the N-H bond and the pyrrole ring in salt 7H+BF4-, no signs of NH···N(n) bonding in it were noticed, and the existing interaction was classified as pure NH···N(π). The results obtained may be useful in studies of secondary protein structures, especially those α-helix sections which contain tryptophan residues.
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Affiliation(s)
- Alexander F Pozharskii
- Department of Organic Chemistry , Southern Federal University , Zorge str. 7 , 344090 Rostov-on-Don , Russian Federation
| | - Valery A Ozeryanskii
- Department of Organic Chemistry , Southern Federal University , Zorge str. 7 , 344090 Rostov-on-Don , Russian Federation
| | - Ekaterina A Filatova
- Department of Organic Chemistry , Southern Federal University , Zorge str. 7 , 344090 Rostov-on-Don , Russian Federation
| | - Olga V Dyablo
- Department of Organic Chemistry , Southern Federal University , Zorge str. 7 , 344090 Rostov-on-Don , Russian Federation
| | - Olga G Pogosova
- Department of Organic Chemistry , Southern Federal University , Zorge str. 7 , 344090 Rostov-on-Don , Russian Federation
| | - Gennady S Borodkin
- Institute of Physical and Organic Chemistry , Southern Federal University , Stachki Avenue 194/2 , 344090 Rostov-on-Don , Russian Federation
| | - Aleksander Filarowski
- Faculty of Chemistry , University of Wroclaw , F. Joliot-Curie 14 , 50-383 Wroclaw , Poland.,Department of Physics , Industrial University of Tyumen , Volodarskogo 38 , 625000 Tyumen , Russian Federation
| | - Dmitriy V Steglenko
- Department of Organic Chemistry , Southern Federal University , Zorge str. 7 , 344090 Rostov-on-Don , Russian Federation.,Institute of Physical and Organic Chemistry , Southern Federal University , Stachki Avenue 194/2 , 344090 Rostov-on-Don , Russian Federation
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Vealey ZN, Foguel L, Vaccaro PH. Spectral Signatures of Proton-Transfer Dynamics at the Cusp of Low-Barrier Hydrogen Bonding. J Phys Chem Lett 2018; 9:4949-4954. [PMID: 30101590 DOI: 10.1021/acs.jpclett.8b02199] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Despite their importance in diverse chemical and biochemical processes, low-barrier hydrogen bonds remain elusive targets to classify and interpret spectroscopically. Here the correlated nature of hydrogen bonding and proton transfer in the low-barrier regime has been probed for the ground and excited electronic states of 6-hydroxy-2-formylfulvene by acquiring jet-cooled fluorescence spectra of the parent and monodeuterated isotopologs. While excited-state profiles reveal regular vibronic patterns devoid of obvious dynamical signatures, their ground-state counterparts display a radically altered energy landscape characterized by spectral bifurcations comparable in magnitude to typical vibrational spacings (>100 cm-1). Quantitative analyses yield unusual deuterium kinetic isotope effects that straddle limiting values attributed to above-barrier vibration and below-barrier tunneling of the proton adjoining donor/acceptor sites. Our findings provide compelling experimental evidence for ultrafast hydron-migration events commensurate with the onset of low-barrier hydrogen bonding and afford a trenchant glimpse of molecular phenomena taking place at the "tipping point" between disparate dynamical regimes.
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Affiliation(s)
- Zachary N Vealey
- Department of Chemistry , Yale University , New Haven , Connecticut 06520-8107 United States
| | - Lidor Foguel
- Department of Chemistry , Yale University , New Haven , Connecticut 06520-8107 United States
| | - Patrick H Vaccaro
- Department of Chemistry , Yale University , New Haven , Connecticut 06520-8107 United States
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Maršalka A, Dagys L, Jakubkienė V, Tumkevičius S, Balevicius V. 1H and 17O NMR study of H-bond dynamics in picolinic acid N-oxide solutions in acetonitrile-h3 and acetonitrile‑d3: Novel aspects of old casus. Chem Phys 2018. [DOI: 10.1016/j.chemphys.2018.06.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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8
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Abstract
A powerful pH-free multicomponent NMR titration method can measure relative acidities, even of closely related compounds, with excellent accuracy. The history of the method is presented, along with details of its implementation and a comparison with earlier NMR titrations using a pH electrode. Many of its areas of applicability are described, especially equilibrium isotope effects. The advantages of the method, some practical considerations, and potential pitfalls are considered.
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Affiliation(s)
- Charles L Perrin
- University of California, San Diego, La Jolla, CA, United States.
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Pylaeva SA, Elgabarty H, Sebastiani D, Tolstoy PM. Symmetry and dynamics of FHF− anion in vacuum, in CD2Cl2 and in CCl4. Ab initio MD study of fluctuating solvent–solute hydrogen and halogen bonds. Phys Chem Chem Phys 2017; 19:26107-26120. [DOI: 10.1039/c7cp04493c] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Asymmetric solvation of FHF− by halogen- and hydrogen-bonding solvents breaks the symmetry of the anion.
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Affiliation(s)
- S. A. Pylaeva
- Institute of Chemistry, Martin-Luther Universität Halle-Wittenberg
- Germany
| | - H. Elgabarty
- Institute of Chemistry, Martin-Luther Universität Halle-Wittenberg
- Germany
| | - D. Sebastiani
- Institute of Chemistry, Martin-Luther Universität Halle-Wittenberg
- Germany
| | - P. M. Tolstoy
- Center for Magnetic Resonance, St. Petersburg State University
- Russia
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10
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Affiliation(s)
- Charles L. Perrin
- Department of Chemistry & Biochemistry University of California, San Diego, La Jolla, California 92093-0358, United States
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11
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Pozharskii AF, Ozeryanskii VA, Mikshiev VY, Antonov AS, Chernyshev AV, Metelitsa AV, Borodkin GS, Fedik NS, Dyablo OV. 10-Dimethylamino Derivatives of Benzo[h]quinoline and Benzo[h]quinazolines: Fluorescent Proton Sponge Analogues with Opposed peri-NMe2/–N═ Groups. How to Distinguish between Proton Sponges and Pseudo-Proton Sponges. J Org Chem 2016; 81:5574-87. [DOI: 10.1021/acs.joc.6b00917] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Alexander F. Pozharskii
- Department
of Chemistry, Southern Federal University, Zorge str. 7, 344090 Rostov-on-Don, Russian Federation
| | - Valery A. Ozeryanskii
- Department
of Chemistry, Southern Federal University, Zorge str. 7, 344090 Rostov-on-Don, Russian Federation
| | - Vladimir Y. Mikshiev
- Department
of Chemistry, Southern Federal University, Zorge str. 7, 344090 Rostov-on-Don, Russian Federation
| | - Alexander S. Antonov
- Department
of Chemistry, Southern Federal University, Zorge str. 7, 344090 Rostov-on-Don, Russian Federation
| | - Anatoly V. Chernyshev
- Institute
of Physical and Organic Chemistry, Southern Federal University, Stachki
Ave. 194/2, 344090 Rostov-on-Don, Russian Federation
| | - Anatoly V. Metelitsa
- Institute
of Physical and Organic Chemistry, Southern Federal University, Stachki
Ave. 194/2, 344090 Rostov-on-Don, Russian Federation
| | - Gennady S. Borodkin
- Institute
of Physical and Organic Chemistry, Southern Federal University, Stachki
Ave. 194/2, 344090 Rostov-on-Don, Russian Federation
| | - Nikita S. Fedik
- Department
of Chemistry, Southern Federal University, Zorge str. 7, 344090 Rostov-on-Don, Russian Federation
| | - Olga V. Dyablo
- Department
of Chemistry, Southern Federal University, Zorge str. 7, 344090 Rostov-on-Don, Russian Federation
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12
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Very strong intramolecular hydrogen bonding of 1,2-dithenoylcyclopentadiene; DFT and spectroscopic studies. J Mol Struct 2014. [DOI: 10.1016/j.molstruc.2014.06.058] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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13
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14
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Ozeryanskii VA, Pozharskii AF, Filarowski A, Borodkin GS. Extreme Magnetic Separation of Geminal Protons in Protonated N,N,N′-Trimethyl-1,8-diaminonaphthalene. A Puzzle of the Fourth Methyl Group. Org Lett 2013; 15:2194-7. [DOI: 10.1021/ol400746u] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Valery A. Ozeryanskii
- Department of Organic Chemistry, Southern Federal University, Zorge 7, 344090 Rostov-on-Don, Russian Federation, Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wroclaw, Poland, and Institute of Physical and Organic Chemistry, Southern Federal University, Stachki 194/2, 344090 Rostov-on-Don, Russian Federation
| | - Alexander F. Pozharskii
- Department of Organic Chemistry, Southern Federal University, Zorge 7, 344090 Rostov-on-Don, Russian Federation, Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wroclaw, Poland, and Institute of Physical and Organic Chemistry, Southern Federal University, Stachki 194/2, 344090 Rostov-on-Don, Russian Federation
| | - Alexander Filarowski
- Department of Organic Chemistry, Southern Federal University, Zorge 7, 344090 Rostov-on-Don, Russian Federation, Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wroclaw, Poland, and Institute of Physical and Organic Chemistry, Southern Federal University, Stachki 194/2, 344090 Rostov-on-Don, Russian Federation
| | - Gennady S. Borodkin
- Department of Organic Chemistry, Southern Federal University, Zorge 7, 344090 Rostov-on-Don, Russian Federation, Faculty of Chemistry, University of Wroclaw, F. Joliot-Curie 14, 50-383 Wroclaw, Poland, and Institute of Physical and Organic Chemistry, Southern Federal University, Stachki 194/2, 344090 Rostov-on-Don, Russian Federation
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Tayyari SF, Laleh S, Zahedi-Tabrizi M, Vakili M. Structure, vibrational assignment, and NMR spectroscopy of 1,2-bis (dichloroacetyl) cyclopentadiene. J Mol Struct 2013. [DOI: 10.1016/j.molstruc.2012.09.069] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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16
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Ip BCK, Shenderovich IG, Tolstoy PM, Frydel J, Denisov GS, Buntkowsky G, Limbach HH. NMR Studies of Solid Pentachlorophenol-4-Methylpyridine Complexes Exhibiting Strong OHN Hydrogen Bonds: Geometric H/D Isotope Effects and Hydrogen Bond Coupling Cause Isotopic Polymorphism. J Phys Chem A 2012; 116:11370-87. [DOI: 10.1021/jp305863n] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Brenda C. K. Ip
- Institut für Chemie und
Biochemie, Freie Universität Berlin, Takustrasse 3, D-14195 Berlin,
Germany
| | - Ilya G. Shenderovich
- Institut für Chemie und
Biochemie, Freie Universität Berlin, Takustrasse 3, D-14195 Berlin,
Germany
- St. Petersburg State University, 198504 St. Petersburg, Russian Federation
| | - Peter M. Tolstoy
- Institut für Chemie und
Biochemie, Freie Universität Berlin, Takustrasse 3, D-14195 Berlin,
Germany
- St. Petersburg State University, 198504 St. Petersburg, Russian Federation
| | - Jaroslaw Frydel
- Institut für Chemie und
Biochemie, Freie Universität Berlin, Takustrasse 3, D-14195 Berlin,
Germany
| | - Gleb S. Denisov
- St. Petersburg State University, 198504 St. Petersburg, Russian Federation
| | - Gerd Buntkowsky
- Eduard-Zintl-Institut für
Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Petersenstr. 20, D-64287 Darmstadt, Germany
| | - Hans-Heinrich Limbach
- Institut für Chemie und
Biochemie, Freie Universität Berlin, Takustrasse 3, D-14195 Berlin,
Germany
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Pozharskii AF, Ozeryanskii VA. Proton Sponges and Hydrogen Transfer Phenomena. MENDELEEV COMMUNICATIONS 2012. [DOI: 10.1016/j.mencom.2012.05.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Perrin CL, Karri P, Moore C, Rheingold AL. Hydrogen-bond symmetry in difluoromaleate monoanion. J Am Chem Soc 2012; 134:7766-72. [PMID: 22519701 DOI: 10.1021/ja2117848] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The symmetry of the hydrogen bond in hydrogen difluoromaleate monoanion is probed by X-ray crystallography and by the NMR method of isotopic perturbation in water, in two aprotic organic solvents, and in an isotropic liquid crystal. The X-ray crystal structure of potassium hydrogen difluoromaleate shows a remarkably short O-O distance of 2.41 Å and equal O-H distances of 1.206 Å, consistent with a strong and symmetric hydrogen bond. Incorporation of (18)O into one carboxyl group allows investigation of the symmetry of the H-bond in solution by the method of isotopic perturbation. The (19)F NMR spectra of the mono-(18)O-substituted monoanion in water, CD(2)Cl(2), and CD(3)CN show an AB spin system, corresponding to fluorines in different environments. The difference is attributed to the perturbation of the acidity of a carboxylic acid by (18)O, not to the mere presence of the (18)O, because the mono-(18)O dianion shows equivalent fluorines. Therefore, it is concluded that the monoanion exists as an equilibrating pair of interconverting tautomers and not as a single symmetric structure not only in water but also in organic solvents. However, in the isotropic liquid crystal phase of 4-cyanophenyl 4-heptylbenzoate, tetrabutylammonium hydrogen difluoromaleate-(18)O shows equivalent fluorines, consistent with a single symmetric structure. These results support earlier studies, which suggested that the symmetry of hydrogen bonds can be determined by the local environment.
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Affiliation(s)
- Charles L Perrin
- Department of Chemistry, University of California-San Diego, La Jolla, California 92093-0358, USA.
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Dopieralski P, Perrin CL, Latajka Z. On the Intramolecular Hydrogen Bond in Solution: Car-Parrinello and Path Integral Molecular Dynamics Perspective. J Chem Theory Comput 2011; 7:3505-13. [PMID: 26598249 DOI: 10.1021/ct200580c] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The issue of the symmetry of short, low-barrier hydrogen bonds in solution is addressed here with advanced ab initio simulations of a hydrogen maleate anion in different environments, starting with the isolated anion, going through two crystal structures (sodium and potassium salts), then to an aqueous solution, and finally in the presence of counterions. By Car-Parrinello and path integral molecular dynamics simulations, it is demonstrated that the position of the proton in the intramolecular hydrogen bond of an aqueous hydrogen maleate anion is entirely related to the solvation pattern around the oxygen atoms of the intramolecular hydrogen bond. In particular, this anion has an asymmetric hydrogen bond, with the proton always located on the oxygen atom that is less solvated, owing to the instantaneous solvation environment. Simulations of water solutions of hydrogen maleate ion with two different counterions, K(+) and Na(+), surprisingly show that the intramolecular hydrogen-bond potential in the case of the Na(+) salt is always asymmetric, regardless of the hydrogen bonds to water, whereas for the K(+) salt, the potential for H motion depends on the location of the K(+). It is proposed that repulsion by the larger and more hydrated K(+) is weaker than that by Na(+) and competitive with solvation by water.
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Affiliation(s)
| | - Charles L Perrin
- Department of Chemistry and Biochemistry, University of California at San Diego , La Jolla, California 92093-0358, United States
| | - Zdzislaw Latajka
- Faculty of Chemistry, University of Wroclaw , Joliot-Curie 14, 50-383 Wroclaw, Poland
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20
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Scerba MT, Leavitt CM, Diener ME, DeBlase AF, Guasco TL, Siegler MA, Bair N, Johnson MA, Lectka T. NH+–F Hydrogen Bonding in a Fluorinated “Proton Sponge” Derivative: Integration of Solution, Solid-State, Gas-Phase, and Computational Studies. J Org Chem 2011; 76:7975-84. [DOI: 10.1021/jo2015328] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Michael T. Scerba
- Department of Chemistry, New Chemistry Building, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - Christopher M. Leavitt
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Matthew E. Diener
- Department of Chemistry, New Chemistry Building, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - Andrew F. DeBlase
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Timothy L. Guasco
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Maxime A. Siegler
- Department of Chemistry, New Chemistry Building, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - Nathaniel Bair
- Department of Chemistry, New Chemistry Building, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, United States
| | - Mark A. Johnson
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Thomas Lectka
- Department of Chemistry, New Chemistry Building, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, United States
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Lankau T, Yu CH. A quantum description of the proton movement in an idealized NHN+ bridge. Phys Chem Chem Phys 2011; 13:12758-69. [DOI: 10.1039/c0cp02172e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Abstract
In a symmetric hydrogen bond (H-bond), the hydrogen atom is perfectly centered between the two donor atoms. The energy diagram for hydrogen motion is thus a single-well potential, rather than the double-well potential of a more typical H-bond, in which the hydrogen is covalently bonded to one atom and H-bonded to the other. Examples of symmetric H-bonds are often found in crystal structures, and they exhibit the distinctive feature of unusually short length: for example, the O-O distance in symmetric OHO H-bonds is found to be less than 2.5 Å. In comparison, the O-O distance in a typical asymmetric H-bond, such as ROH···OR(2), ranges from about 2.7 to 3.0 Å. In this Account, we briefly review and update our use of the method of isotopic perturbation to search for a symmetric, centered, or single-well-potential H-bond in solution. Such low-barrier H-bonds are thought to be unusually strong, owing perhaps to the resonance stabilization of two identical resonance forms [A-H···B ↔ A···H-B]. This presumptive bond strength has been invoked to explain some enzyme-catalyzed reactions. Yet in solution, a wide variety of OHO, OHN, and NHN H-bonds have all been found to be asymmetric, in double-well potentials. Examples include the monoanion of (±)-2,3-di-tert-butylsuccinic acid and a protonated tetramethylnaphthalenediamine, even though these two ions are often considered prototypes of species with strong H-bonds. In fact, all of the purported examples of strong, symmetric H-bonds have been found to exist in solution as pairs of asymmetric tautomers, in contrast to their symmetry in some crystals. The asymmetry can be attributed to the disorder of the local solvation environment, which leads to an equilibrium among solvatomers (that is, isomers that differ in solvation). If the disorder of the local environment is sufficient to break symmetry, then symmetry itself is not sufficient to stabilize the H-bond, and symmetric H-bonds do not have an enhanced stability or an unusual strength. Nor are short H-bonds unusually strong. We discuss previous evidence for "short, strong, low-barrier" H-bonds and show it to be based on ambiguous comparisons. The role of such H-bonds in enzyme-catalyzed reactions is then ascribed not to any unusual strength of the H-bond itself but to relief of "strain."
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Affiliation(s)
- Charles L. Perrin
- Department of Chemistry & Biochemistry, University of California—San Diego, La Jolla, California 92093-0358, United States
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Enk B, Eisenstecken D, Kopacka H, Wurst K, Müller T, Pevny F, Winter RF, Bildstein B. Doubly N-Functionalized Pentafulvenes and Redox-Responsive [N,N]- and [N,C,N]-Pincer Bis(imidoyl)pentamethylruthenocene Metalloligands. Organometallics 2010. [DOI: 10.1021/om100458h] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Barbara Enk
- Institute of General, Inorganic and Theoretical Chemistry, Faculty of Chemistry and Pharmacy, University of Innsbruck, Innrain 52a, 6020 Innsbruck, Austria
| | - Daniela Eisenstecken
- Institute of General, Inorganic and Theoretical Chemistry, Faculty of Chemistry and Pharmacy, University of Innsbruck, Innrain 52a, 6020 Innsbruck, Austria
| | - Holger Kopacka
- Institute of General, Inorganic and Theoretical Chemistry, Faculty of Chemistry and Pharmacy, University of Innsbruck, Innrain 52a, 6020 Innsbruck, Austria
| | - Klaus Wurst
- Institute of General, Inorganic and Theoretical Chemistry, Faculty of Chemistry and Pharmacy, University of Innsbruck, Innrain 52a, 6020 Innsbruck, Austria
| | - Thomas Müller
- Institute of Organic Chemistry, Faculty of Chemistry and Pharmacy, University of Innsbruck, Innrain 52a, 6020 Innsbruck, Austria
| | - Florian Pevny
- Department of Chemistry, University of Konstanz, Universitätstrasse 10, D-78457 Konstanz, Germany
| | - Rainer F. Winter
- Department of Chemistry, University of Konstanz, Universitätstrasse 10, D-78457 Konstanz, Germany
| | - Benno Bildstein
- Institute of General, Inorganic and Theoretical Chemistry, Faculty of Chemistry and Pharmacy, University of Innsbruck, Innrain 52a, 6020 Innsbruck, Austria
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24
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Perrin CL. Secondary equilibrium isotope effects on acidity. ADVANCES IN PHYSICAL ORGANIC CHEMISTRY 2010. [DOI: 10.1016/s0065-3160(08)44003-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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25
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Abstract
A classic question regarding hydrogen bonds (H-bonds) concerns their symmetry. Is the hydrogen centered or is it closer to one donor and jumping between them? These possibilities correspond to single- and double-well potentials, respectively. The NMR method of isotopic perturbation can answer this question. It is illustrated with 3-hydroxy-2-phenylpropenal and then applied to dicarboxylate monoanions. The 18O-induced 13C NMR splittings signify that their intramolecular H-bonds are asymmetric and that each species is a pair of tautomers, not a single symmetric structure, even though maleate and phthalate are symmetric in crystals. The asymmetry is seen across a wide range of solvents and a wide variety of monoanions, including 2,3-di-tert-butylsuccinate and zwitterionic phthalates. Asymmetry is also seen in monoprotonated 1,8-bis(dimethylamino)naphthalenediamines, N,N'-diaryl-6-aminofulvene-2-aldimines, and 6-hydroxy-2-formylfulvene. The asymmetry is attributed to the disorder of the local environment, establishing an equilibrium between solvatomers. The broader implications of these results regarding the role of solvation in breaking symmetry are discussed. It was prudent to confirm a secondary deuterium isotope effect (IE) on amine basicity by NMR titration of a mixture of PhCH2NH2 and PhCHDNH2. The IE is of stereoelectronic origin. It is proposed that symmetric H-bonds can be observed in crystals but not in solution because a disordered environment induces asymmetry, whereas a crystal can guarantee a symmetric environment. The implications for the controversial role of low-barrier H-bonds in enzyme-catalyzed reactions are discussed.
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Affiliation(s)
- Charles L. Perrin
- 1Department of Chemistry, University of California, San Diego, La Jolla, CA 92093-0358, USA
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26
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Ozeryanskii V, Shevchuk D, Pozharskii A, Kazheva O, Chekhlov A, Dyachenko O. Protonation of naphthalene proton sponges containing higher N-alkyl groups. Structural consequences on proton accepting properties and intramolecular hydrogen bonding. J Mol Struct 2008. [DOI: 10.1016/j.molstruc.2008.04.051] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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27
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Yamane K, Hayashi S, Nakanishi W, Sasamori T, Tokitoh N. Fine structures of 1-(arylethynylselanyl)naphthalenes: Characteristic features brought by the ethynylselanyl group. Polyhedron 2008. [DOI: 10.1016/j.poly.2008.04.052] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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28
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Yaghmaei S, Khodagholian S, Kaiser JM, Tham FS, Mueller LJ, Morton TH. Chelation of a Proton by an Aliphatic Tertiary Diamine. J Am Chem Soc 2008; 130:7836-8. [DOI: 10.1021/ja8018725] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sepideh Yaghmaei
- Department of Chemistry, University of California, Riverside, California 92521-0403
| | - Sevana Khodagholian
- Department of Chemistry, University of California, Riverside, California 92521-0403
| | - J. Michael Kaiser
- Department of Chemistry, University of California, Riverside, California 92521-0403
| | - Fook S. Tham
- Department of Chemistry, University of California, Riverside, California 92521-0403
| | - Leonard J. Mueller
- Department of Chemistry, University of California, Riverside, California 92521-0403
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29
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Chmielewski P, Ozeryanskii VA, Sobczyk L, Pozharskii AF. Primary1H/2H isotope effect in the NMR chemical shift of HClO4 salts of 1,8-bis(dimethylamino)naphthalene derivatives. J PHYS ORG CHEM 2007. [DOI: 10.1002/poc.1219] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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30
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Hansen PE. Isotope effect on chemical shifts in hydrogen-bonded systems. J Labelled Comp Radiopharm 2007. [DOI: 10.1002/jlcr.1440] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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31
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Bailey PJ, Melchionna M, Parsons S. Ambidentate Character of the 6-Aminofulvene-2-aldiminate Ligand Containing Both Diimine and Cyclopentadienyl Donors. Organometallics 2006. [DOI: 10.1021/om060808d] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Philip J. Bailey
- School of Chemistry, University of Edinburgh, The King's Buildings, West Mains Road, Edinburgh, EH9 3JJ, U.K
| | - Michele Melchionna
- School of Chemistry, University of Edinburgh, The King's Buildings, West Mains Road, Edinburgh, EH9 3JJ, U.K
| | - Simon Parsons
- School of Chemistry, University of Edinburgh, The King's Buildings, West Mains Road, Edinburgh, EH9 3JJ, U.K
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32
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Toom L, Kütt A, Kaljurand I, Leito I, Ottosson H, Grennberg H, Gogoll A. Substituent Effects on the Basicity of 3,7-Diazabicyclo[3.3.1]nonanes. J Org Chem 2006; 71:7155-64. [PMID: 16958508 DOI: 10.1021/jo0604991] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Basicity constants for a series of 3,7-diazabicyclo[3.3.1]nonane derivatives in acetonitrile with a variation over 13 orders of magnitude have been determined using a spectrophotometric titration technique. An excellent correlation between basicity and calculated proton affinities obtained at PCM-B3LYP/6-31+G(d)//B3LYP/6-31G(d) level was found. The results are discussed in terms of substituent effects and compared to (15)N NMR chemical shifts.
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Affiliation(s)
- Lauri Toom
- Department of Biochemistry and Organic Chemistry, Uppsala University, Box 576, SE-75123, Uppsala, Sweden
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33
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Perrin CL, Lau JS. Hydrogen-Bond Symmetry in Zwitterionic Phthalate Anions: Symmetry Breaking by Solvation. J Am Chem Soc 2006; 128:11820-4. [PMID: 16953621 DOI: 10.1021/ja063797o] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The cationic nitrogen of zwitterion 1 is located symmetrically with respect to its intramolecular OHO hydrogen bond. Incorporation of one (18)O allows investigation of the H-bond symmetry by the NMR method of isotopic perturbation. In both CD(3)OD and CD(2)Cl(2) equilibrium isotope shifts are detected at the carboxyl and ipso carbons. Therefore, 1 exists as a pair of interconverting tautomers, not as a single symmetric structure with its hydrogen centered between the two oxygens. The H-bond is instantaneously asymmetric, and there is an equilibrium between solvatomers (isomers or stereoisomers that differ in solvation). The broader implications of this result regarding the role of the local environment ("solvation") in breaking symmetry are discussed.
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Affiliation(s)
- Charles L Perrin
- Department of Chemistry, University of California-San Diego, La Jolla, California 92093-0506, USA.
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34
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Golubev NS, Tolstoi PM, Shchepkin DN. Estimation of the contribution of vibronic interaction to the isotope effect on the nuclear magnetic shielding constant of a hydrogen bridge. RUSS J GEN CHEM+ 2006. [DOI: 10.1134/s1070363206080019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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35
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Ozeryanskii VA, Pozharskii AF, Schilf W, Kamieński B, Sawka-Dobrowolska W, Sobczyk L, Grech E. Novel Polyfunctional Tautomeric Systems Containing Salicylideneamino and Proton Sponge Moieties. European J Org Chem 2006. [DOI: 10.1002/ejoc.200500574] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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36
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Tayyari S, Zahedi-Tabrizi M, Rahemi H, Mirshahi H, Emampour J, Rajabi M, Milani-Nejad F. A two-dimensional potential function for bent hydrogen bonded systems. II-6-hydroxy-2-formylfulvene. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.theochem.2005.06.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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37
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Raczyńska ED, Rudka T, Darowska M, Dąbkowska I, Gal JF, Maria PC. Experimental (FT-ICR) and theoretical (DFT) estimation of the basic site preference for the bidentate molecule 2-(β-aminoethyl)-pyridine: similarity with histamine. J PHYS ORG CHEM 2005. [DOI: 10.1002/poc.954] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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38
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Alder RW. Design of C2-Chiral Diamines That Are Computationally Predicted To Be a Million-fold More Basic than the Original Proton Sponges. J Am Chem Soc 2005; 127:7924-31. [PMID: 15913383 DOI: 10.1021/ja051049d] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A set of C2-chiral diamines 18-21 based on 1,6-diazacyclodecane have been identified whose conjugate acids are predicted by B3LYP/6-31G calculations to have pKa values of approximately 23-6 on the water scale (pKa = 30-33 in MeCN); they are also expected to be kinetically active, but essentially nonnucleophilic. Strain relief on protonation largely determines the basicity of these compounds, and the key to the design of stronger bases is limiting conformational freedom, especially by preventing nitrogen inversion, through the introduction of additional ring fusions. 15,16-Dimethyl-15,16-diazatricyclo[9.3.1.1(4,8)]hexadecane (20) is examined in detail and shown to exist in 10 diastereomeric forms as a result of in-/out-isomerism. The predicted pKa values for these diastereomers range over 14 log units.
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Affiliation(s)
- Roger W Alder
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom.
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39
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Ozeryanskii V, Pozharskii A, Koroleva M, Shevchuk D, Kazheva O, Chekhlov A, Shilov G, Dyachenko O. N,N,N′-Trialkyl-1,8-diaminonaphthalenes: convenient method of preparation from protonated proton sponges and the first X-ray information. Tetrahedron 2005. [DOI: 10.1016/j.tet.2005.02.067] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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40
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Raczyńska ED, Darowska M, Dabkowska I, Decouzon M, Gal JF, Maria PC, Poliart CD. Experimental and Theoretical Evidence of Basic Site Preference in Polyfunctional Superbasic Amidinazine: N1,N1-Dimethyl-N2-β-(2-pyridylethyl)formamidine. J Org Chem 2004; 69:4023-30. [PMID: 15176827 DOI: 10.1021/jo030308j] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The gas-phase basicity (GB) of the flexible polyfunctional N(1),N(1)-dimethyl-N(2)-beta-(2-pyridylethyl)formamidine (1) containing two potential basic sites (the ring N-aza and the chain N-imino) is obtained from proton-transfer equilibrium constant measurements, using Fourier-transform ion-cyclotron resonance mass spectrometry. Comparison of the experimental GB obtained for 1 with those reported for model amidines and azines indicates that the chain N-imino in the amidine group is the favored site of protonation. Semiempirical (AM1) and ab initio calculations (HF, MP2, and DFT), performed for 1 and its protonated forms, confirm this interpretation. These results are in contrast to those found previously for N(1),N(1)-dimethyl-N(2)-azinylformamidines (containing the amidine function directly linked to the azinyl ring), in which the ring N-aza is the most basic site in the gas phase. The separation of the two potential basic sites in 1 by the ethylene chain interrupts the resonance conjugation between the two functions and changes their relative basicities and, thus, the preferable site of protonation. It also increases the chelation effect against the proton and the gas-phase basicity of 1 in such a magnitude that consequently 1 may be classified as a superbase (GB = 241.1 kcal mol(-)(1)). A transition state corresponding to the internal transfer of the proton (ITP) between the ring N-aza and the chain N-imino in 1 is investigated at the DFT(B3LYP)/6-31G level. The energy barrier calculated for the ITP between the two basic sites is small and vanishes when zero-point vibrational terms and thermal corrections are applied to obtain the enthalpy or Gibbs energy of activation for the proton transfer. Additional calculations at the DFT(MPW1K)/6-31G level confirm this behavior. This indicates that the quantum-chemical ITP in 1 has a single-well character. The proton is located on the N-imino site, and the H-bond is formed with the N-aza site.
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Affiliation(s)
- Ewa D Raczyńska
- Department of Chemistry, Agricultural University (SGGW) 02776 Warszawa, Poland.
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41
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Perrin CL, Ohta BK, Kuperman J. β-Deuterium Isotope Effects on Amine Basicity, “Inductive” and Stereochemical. J Am Chem Soc 2003; 125:15008-9. [PMID: 14653734 DOI: 10.1021/ja038343v] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Secondary beta deuterium isotope effects on acidity constants of ammonium ions are measured using a remarkably precise NMR titration method. Deuteration is found to increase the basicity of methylamine, dimethylamine, benzylamine, and N,N-dimethylaniline. The effect is attributed to a lowered zero-point energy of a CH bond adjacent to an amine nitrogen. The method permits a determination of the stereochemical dependence of the isotope effect in a locked piperidine, and it is found that deuteration is more effective when antiperiplanar to a lone pair. The values are consistent with a cos(2) dependence on dihedral angle, with no detectable angle-independent inductive effect.
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Affiliation(s)
- Charles L Perrin
- Department of Chemistry 0358, University of California, San Diego, La Jolla, California 92093-0358, USA
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