1
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O’Neill RT, Boulatov R. The Contributions of Model Studies for Fundamental Understanding of Polymer Mechanochemistry. Synlett 2021. [DOI: 10.1055/a-1710-5656] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
AbstractThe exciting field of polymer mechanochemistry has made great empirical progress in discovering reactions in which a stretching force accelerates scission of strained bonds using single molecule force spectroscopy and ultrasonication experiments. Understanding why these reactions happen, i.e., the fundamental physical processes that govern coupling of macroscopic motion to chemical reactions, as well as discovering other patterns of mechanochemical reactivity require complementary techniques, which permit a much more detailed characterization of reaction mechanisms and the distribution of force in reacting molecules than are achievable in SMFS or ultrasonication. A molecular force probe allows the specific pattern of molecular strain that is responsible for localized reactions in stretched polymers to be reproduced accurately in non-polymeric substrates using molecular design rather than atomistically intractable collective motions of millions of atoms comprising macroscopic motion. In this review, we highlight the necessary features of a useful molecular force probe and describe their realization in stiff stilbene macrocycles. We describe how studying these macrocycles using classical tools of physical organic chemistry has allowed detailed characterizations of mechanochemical reactivity, explain some of the most unexpected insights enabled by these probes, and speculate how they may guide the next stage of mechanochemistry.
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Affiliation(s)
| | - Roman Boulatov
- Department of Chemistry, University of Liverpool
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University
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2
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O’Neill RT, Boulatov R. The many flavours of mechanochemistry and its plausible conceptual underpinnings. Nat Rev Chem 2021; 5:148-167. [PMID: 37117533 DOI: 10.1038/s41570-020-00249-y] [Citation(s) in RCA: 131] [Impact Index Per Article: 43.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/23/2020] [Indexed: 12/12/2022]
Abstract
Mechanochemistry describes diverse phenomena in which mechanical load affects chemical reactivity. The fuzziness of this definition means that it includes processes as seemingly disparate as motor protein function, organic synthesis in a ball mill, reactions at a propagating crack, chemical actuation, and polymer fragmentation in fast solvent flows and in mastication. In chemistry, the rate of a reaction in a flask does not depend on how fast the flask moves in space. In mechanochemistry, the rate at which a material is deformed affects which and how many bonds break. In other words, in some manifestations of mechanochemistry, macroscopic motion powers otherwise endergonic reactions. In others, spontaneous chemical reactions drive mechanical motion. Neither requires thermal or electrostatic gradients. Distinct manifestations of mechanochemistry are conventionally treated as being conceptually independent, which slows the field in its transformation from being a collection of observations to a rigorous discipline. In this Review, we highlight observations suggesting that the unifying feature of mechanochemical phenomena may be the coupling between inertial motion at the microscale to macroscale and changes in chemical bonding enabled by transient build-up and relaxation of strains, from macroscopic to molecular. This dynamic coupling across multiple length scales and timescales also greatly complicates the conceptual understanding of mechanochemistry.
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3
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Okuma K, Qu Y, Nagahora N. Novel Reaction Course of Thiiranes to Vinyloxiranes: Reaction of Benzyne with Thiiranes and Aldehydes. HETEROCYCLES 2021. [DOI: 10.3987/com-21-14465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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4
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Collison S, Harger MJP. Reactivity of ω-hydroxyalkylphosphinic Anilides in Cyclisation by Intramolecular Displacement of the Aniline Moiety. JOURNAL OF CHEMICAL RESEARCH 2019. [DOI: 10.3184/030823400103165563] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A cyclic phosphinate 2 is formed when HO(CH2) n+3P(O)(NHPh)Ph ( n = 0 or 1) is treated with acid (P–N bond cleavage); five-membered ring formation ( n= 0) is 70 times faster than six in CHCI3 and 50 times faster in MeOH.
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Affiliation(s)
- Shaun Collison
- Department of Chemistry, The University, Leicester, LE1 7RH, UK
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5
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Baker MB, Ferreira RB, Tasseroul J, Lampkins AJ, Al Abbas A, Abboud KA, Castellano RK. Selective and Sequential Aminolysis of Benzotrifuranone: Synergism of Electronic Effects and Ring Strain Gradient. J Org Chem 2016; 81:9279-9288. [DOI: 10.1021/acs.joc.6b01867] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Matthew B. Baker
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
| | - Renan B. Ferreira
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
| | - Jonathan Tasseroul
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
| | - Andrew J. Lampkins
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
| | - Alexandre Al Abbas
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
| | - Khalil A. Abboud
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
| | - Ronald K. Castellano
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
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6
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Krenske EH, Williams CM. Do Anti-Bredt Natural Products Exist? Olefin Strain Energy as a Predictor of Isolability. Angew Chem Int Ed Engl 2015; 54:10608-12. [PMID: 26235843 DOI: 10.1002/anie.201503822] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Indexed: 01/29/2023]
Abstract
Bredt's rule holds a special place in the realm of physical organic chemistry, but its application to natural products chemistry—the field in which the rule was originally formulated—is not well defined. Herein, the use of olefin strain (OS) energy as a readily calculated predictor of the stability of natural products containing a bridgehead alkene is introduced. Schleyer first used OS energies to classify parent bridgehead alkenes into "isolable", "observable", and "unstable" classes. OS calculations on natural products, using contemporary forcefield methods, unequivocally predict all structurally verified bridgehead alkene natural products to be "isolable". Thus, when one assigns the structure of a putative bridgehead alkene natural product, an OS in the "observable" or "unstable" ranges is a red flag for error.
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Affiliation(s)
- Elizabeth H Krenske
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, 4072, Queensland (Australia) http://www.scmb.uq.edu.au/homepages/williams/index.html.
| | - Craig M Williams
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, 4072, Queensland (Australia) http://www.scmb.uq.edu.au/homepages/williams/index.html.
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7
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Krenske EH, Williams CM. Do Anti-Bredt Natural Products Exist? Olefin Strain Energy as a Predictor of Isolability. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201503822] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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8
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Christmann M, Hu J, Kitamura M, Stoltz B. Tetrahedron reports on organic chemistry. Tetrahedron 2015. [DOI: 10.1016/s0040-4020(15)00744-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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9
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Marino MG, Kreuer KD. Alkaline stability of quaternary ammonium cations for alkaline fuel cell membranes and ionic liquids. CHEMSUSCHEM 2015; 8:513-23. [PMID: 25431246 DOI: 10.1002/cssc.201403022] [Citation(s) in RCA: 293] [Impact Index Per Article: 32.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Indexed: 05/08/2023]
Abstract
The alkaline stability of 26 different quaternary ammonium groups (QA) is investigated for temperatures up to 160 °C and NaOH concentrations up to 10 mol L(-1) with the aim to provide a basis for the selection of functional groups for hydroxide exchange membranes in alkaline fuel cells and of ionic-liquid cations stable in basic conditions. Most QAs exhibit unexpectedly high alkaline stability with the exception of aromatic cations. β-Protons are found to be far less susceptible to nucleophilic attack than previously suggested, whereas the presence of benzyl groups, nearby hetero-atoms, or other electron-withdrawing species promote degradation reactions significantly. Cyclic QAs proved to be exceptionally stable, with the piperidine-based 6-azonia-spiro[5.5]undecane featuring the highest half-life at the chosen conditions. Absolute and relative stabilities presented herein stand in contrast to literature data, the differences being ascribed to solvent effects on degradation.
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Affiliation(s)
- M G Marino
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart (Germany).
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10
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Martín C, Fiorani G, Kleij AW. Recent Advances in the Catalytic Preparation of Cyclic Organic Carbonates. ACS Catal 2015. [DOI: 10.1021/cs5018997] [Citation(s) in RCA: 758] [Impact Index Per Article: 84.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Carmen Martín
- Institute of Chemical Research of Catalonia (ICIQ), Avenida Països Catalans 16, 43007 Tarragona, Spain
| | - Giulia Fiorani
- Institute of Chemical Research of Catalonia (ICIQ), Avenida Països Catalans 16, 43007 Tarragona, Spain
| | - Arjan W. Kleij
- Institute of Chemical Research of Catalonia (ICIQ), Avenida Països Catalans 16, 43007 Tarragona, Spain
- Catalan Institute of Research and Advanced Studies (ICREA), Passeig Lluís Companys 23, 08010 Barcelona, Spain
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11
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Mak JYW, Pouwer RH, Williams CM. Naturstoffe mit Anti-Bredt- und Brückenkopf-Doppelbindung. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201400932] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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12
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Mak JYW, Pouwer RH, Williams CM. Natural products with anti-Bredt and bridgehead double bonds. Angew Chem Int Ed Engl 2014; 53:13664-88. [PMID: 25399486 DOI: 10.1002/anie.201400932] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 04/25/2014] [Indexed: 11/11/2022]
Abstract
Well over a hundred years ago, Professor Julius Bredt embarked on a career pursuing and critiquing bridged bicyclic systems that contained ring strain induced by the presence of a bridgehead olefin. These endeavors founded what we now know as Bredt's rule (Bredtsche Regel). Physical, theoretical, and synthetic organic chemists have intensely studied this premise, pushing the boundaries of such systems to arrive at a better understood physical phenomenon. Mother nature has also seen fit to construct molecules containing bridgehead double bonds that encompass Bredt's rule. For the first time, this topic is reviewed in a natural product context.
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Affiliation(s)
- Jeffrey Y W Mak
- Institute for Molecular Bioscience, The University of Queensland, Brisbane (Australia)
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13
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Stoltz B, Motherwell W. Tetrahedron reports on organic chemistry. Tetrahedron 2013. [DOI: 10.1016/s0040-4020(13)01252-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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14
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Orr D, Tolfrey A, Percy JM, Frieman J, Harrison ZA, Campbell-Crawford M, Patel VK. Single-Step Microwave-Mediated Synthesis of Oxazoles and Thiazoles from 3-Oxetanone: A Synthetic and Computational Study. Chemistry 2013; 19:9655-62. [DOI: 10.1002/chem.201301011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2013] [Indexed: 11/07/2022]
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15
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Yeoh SD, Skene CE, White JM. Hyperconjugation involving strained carbon-carbon bonds. structural analysis of ester and ether derivatives and one-bond 13C-13C coupling constants of α- and β-nopinol. J Org Chem 2013; 78:311-9. [PMID: 23215360 DOI: 10.1021/jo3020243] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
σ(C-C)-σ*(C-O) interactions involving the strained carbon-carbon bonds of α- and β-nopinol, and their ester and ether derivatives have been demonstrated in the solid state using the variable oxygen probe. These hyperconjugative interactions are manifested as a strong response of the C-OR bond distance to the electron demand of the OR substituent. Although the effects upon the donor C-C bond distances are not large enough to be measurable by X-ray crystallography, they do result in systematic and measurable effects on the (13)C-(13)C one-bond coupling constants. For the donor C-C bond, coupling constants decrease, consistent with weakening of this bond, while the intervening C-C bond coupling constants increase, consistent with bond strengthening, as the electron demand of OR increases.
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Affiliation(s)
- Shinn Dee Yeoh
- School of Chemistry and Bio-21 Institute, University of Melbourne, Parkville, Victoria 3010, Australia
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17
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Stoltz B, Motherwell W. Tetrahedron reports on organic chemistry. Tetrahedron 2011. [DOI: 10.1016/s0040-4020(11)00770-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Abstract
The purpose of this critical review is to introduce the reader to an increasingly important class of phenomena: enormous changes in rates of simple chemical reactions within macromolecules as they are stretched by interactions with the environment. In these chemomechanical, or mechanochemical, phenomena the effect of the macromolecular environment can be visualized as a spring (harmonic or anharmonic) bridging and pulling apart a pair of atoms of the macromolecule. Being able to predict how the parameters of this spring affect the kinetics of the reactions occurring between the constrained atoms may create revolutionary opportunities for designing new reactions, molecules and materials that would capture large-scale deformations to drive useful chemistry or, conversely, that would propel autonomous micro- and nanomechanical devices by coupling them to the concerted motion of atoms that convert reactants into products. Although chemists have long studied and exploited coupling between molecular strain and reactivity in small molecules, a quantitative understanding of the relationship between large-scale (>50 nm) strain and localized reactivity presents unique conceptual and experimental challenges. Below we discuss both the phenomenology and the interpretive framework of chemomechanical phenomena (102 references).
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Affiliation(s)
- Zhen Huang
- Department of Chemistry, University of Illinois, Urbana, IL 61801, USA
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19
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Kucharski TJ, Boulatov R. The physical chemistry of mechanoresponsive polymers. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c0jm04079g] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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20
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Stoltz B, Motherwell W. Tetrahedron reports on organic chemistry. Tetrahedron 2010. [DOI: 10.1016/s0040-4020(10)01735-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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21
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Dugarte NY, Erben MF, Romano RM, Ge MF, Li Y, Della Védova CO. Matrix Photochemistry at Low Temperatures and Spectroscopic Properties of γ-Butyrothiolactone. J Phys Chem A 2010; 114:9462-70. [DOI: 10.1021/jp105767y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Nahir Y. Dugarte
- CEQUINOR (UNLP-CONICET, CCT La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, C.C. 962 (1900), La Plata, República Argentina, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China, and LaSeISiC (CIC-UNLP-CONICET), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Camino Centenario y 508, Gonnet, República Argentina
| | - Mauricio F. Erben
- CEQUINOR (UNLP-CONICET, CCT La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, C.C. 962 (1900), La Plata, República Argentina, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China, and LaSeISiC (CIC-UNLP-CONICET), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Camino Centenario y 508, Gonnet, República Argentina
| | - Rosana M. Romano
- CEQUINOR (UNLP-CONICET, CCT La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, C.C. 962 (1900), La Plata, República Argentina, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China, and LaSeISiC (CIC-UNLP-CONICET), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Camino Centenario y 508, Gonnet, República Argentina
| | - Mao-Fa Ge
- CEQUINOR (UNLP-CONICET, CCT La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, C.C. 962 (1900), La Plata, República Argentina, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China, and LaSeISiC (CIC-UNLP-CONICET), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Camino Centenario y 508, Gonnet, República Argentina
| | - Yao Li
- CEQUINOR (UNLP-CONICET, CCT La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, C.C. 962 (1900), La Plata, República Argentina, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China, and LaSeISiC (CIC-UNLP-CONICET), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Camino Centenario y 508, Gonnet, República Argentina
| | - Carlos O. Della Védova
- CEQUINOR (UNLP-CONICET, CCT La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, C.C. 962 (1900), La Plata, República Argentina, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China, and LaSeISiC (CIC-UNLP-CONICET), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Camino Centenario y 508, Gonnet, República Argentina
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22
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Banks HD. Is nucleophilic cleavage chemistry practical for 4-membered heterocycles? Org Biomol Chem 2009; 7:4496-501. [PMID: 19830301 DOI: 10.1039/b908861j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
A computational study at the MP2(Full)/6-311++G(d,p)//MP2(Full)/6-31+G(d) level of the ammonolysis of halogen substituted azetidines, oxetanes and thietanes was performed in the gas phase and in the commonly used solvent, acetonitrile. Using the free energy of activation of a benchmark reaction for evaluation of synthetic viability, several haloazetidines and oxetanes that possessed the required reactivity were identified; however, no substituted thietane investigated herein was determined to be synthetically useful under the mild conditions selected for this study. In the case of the azetidines, the side reaction of displacement of halide ion was determined to be the preferred reaction course in acetonitrile; however, the amino product of the reactions of the 2-haloazetidines cleaved at an acceptable rate under mild conditions. For the oxetane derivatives investigated, 2-fluorooxetane proved to be a direct source of ring cleavage product. Nucleophilic cleavage of halogen-substituted azetidines and oxetanes is predicted to be a viable source of functionalized three-carbon moieties under mild conditions in organic synthesis.
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Affiliation(s)
- Harold D Banks
- U.S. Army Edgewood Chemical Biological Center, APG, Maryland 21010-5424, USA.
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Volta L, Stirling CJM. Methylenecyclopropanes in Elimination and Addition Reactions: Quantification of the Effects of Strain. PHOSPHORUS SULFUR 2009. [DOI: 10.1080/10426500902947856] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Luca Volta
- a Department of Chemistry , The University of Sheffield , Sheffield, UK
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Yang QZ, Huang Z, Kucharski TJ, Khvostichenko D, Chen J, Boulatov R. A molecular force probe. NATURE NANOTECHNOLOGY 2009; 4:302-6. [PMID: 19421215 DOI: 10.1038/nnano.2009.55] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2008] [Accepted: 02/25/2009] [Indexed: 05/09/2023]
Abstract
Force probes allow reaction rates to be measured as a function of the restoring force in a molecule that has been stretched or compressed. Unlike strain energy, approaches based on restoring force allow quantitative molecular understanding of phenomena as diverse as translation of microscopic objects by reacting molecules, crack propagation and mechanosensing. Conceptually, localized reactions offer the best opportunity to gain fundamental insights into how rates vary with restoring forces, but such reactions are particularly difficult to study systematically using microscopic force probes. Here, we show how a molecular force probe, stiff stilbene, simplifies force spectroscopy of localized reactions. We illustrate the capabilities of our approach by validating the central postulate of chemomechanical kinetics--force lowers the activation barrier proportionally to the difference in a single internuclear distance between the ground and transition states projected on the force vector--on a paradigmatic unimolecular reaction: concerted dissociation of the C-C bond.
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Affiliation(s)
- Qing-Zheng Yang
- Department of Chemistry, University of Illinois, Urbana, Illinois 61801, USA
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25
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Dugarte NY, Erben MF, Romano RM, Boese R, Ge MF, Li Y, Della Védova CO. Matrix Photochemistry, Photoelectron Spectroscopy, Solid-Phase Structure, and Ring Strain Energy of β-Propiothiolactone. J Phys Chem A 2009; 113:3662-72. [DOI: 10.1021/jp811480v] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Nahir Y. Dugarte
- CEQUINOR (UNLP-CONICET, CCT-La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CC 962 (1900), La Plata, República Argentina, Institut für Anorganische Chemie, Universität Duisburg-Essen, Universitätsstrasse 5-7, D-45117 Essen, Germany, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China, and LaSeISiC (CIC-UNLP-CONICET), Departamento de Química, Facultad de
| | - Mauricio F. Erben
- CEQUINOR (UNLP-CONICET, CCT-La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CC 962 (1900), La Plata, República Argentina, Institut für Anorganische Chemie, Universität Duisburg-Essen, Universitätsstrasse 5-7, D-45117 Essen, Germany, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China, and LaSeISiC (CIC-UNLP-CONICET), Departamento de Química, Facultad de
| | - Rosana M. Romano
- CEQUINOR (UNLP-CONICET, CCT-La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CC 962 (1900), La Plata, República Argentina, Institut für Anorganische Chemie, Universität Duisburg-Essen, Universitätsstrasse 5-7, D-45117 Essen, Germany, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China, and LaSeISiC (CIC-UNLP-CONICET), Departamento de Química, Facultad de
| | - Roland Boese
- CEQUINOR (UNLP-CONICET, CCT-La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CC 962 (1900), La Plata, República Argentina, Institut für Anorganische Chemie, Universität Duisburg-Essen, Universitätsstrasse 5-7, D-45117 Essen, Germany, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China, and LaSeISiC (CIC-UNLP-CONICET), Departamento de Química, Facultad de
| | - Mao-Fa Ge
- CEQUINOR (UNLP-CONICET, CCT-La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CC 962 (1900), La Plata, República Argentina, Institut für Anorganische Chemie, Universität Duisburg-Essen, Universitätsstrasse 5-7, D-45117 Essen, Germany, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China, and LaSeISiC (CIC-UNLP-CONICET), Departamento de Química, Facultad de
| | - Yao Li
- CEQUINOR (UNLP-CONICET, CCT-La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CC 962 (1900), La Plata, República Argentina, Institut für Anorganische Chemie, Universität Duisburg-Essen, Universitätsstrasse 5-7, D-45117 Essen, Germany, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China, and LaSeISiC (CIC-UNLP-CONICET), Departamento de Química, Facultad de
| | - Carlos O. Della Védova
- CEQUINOR (UNLP-CONICET, CCT-La Plata), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CC 962 (1900), La Plata, República Argentina, Institut für Anorganische Chemie, Universität Duisburg-Essen, Universitätsstrasse 5-7, D-45117 Essen, Germany, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China, and LaSeISiC (CIC-UNLP-CONICET), Departamento de Química, Facultad de
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26
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Tetrahedron reports on organic chemistry. Tetrahedron 2008. [DOI: 10.1016/s0040-4020(08)00897-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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27
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Beaver MG, Billings SB, Woerpel KA. Nucleophilic Substitution Reactions of 2‐Phenylthio‐Substituted Carbohydrate Acetals and Related Systems: Episulfonium Ions vs. Oxocarbenium Ions as Reactive Intermediates. European J Org Chem 2008. [DOI: 10.1002/ejoc.200700911] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Matthew G. Beaver
- Department of Chemistry, University of California, Irvine, California 92697‐2025, USA, Fax: +1‐949‐824‐9920
| | - Susan B. Billings
- Department of Chemistry, University of California, Irvine, California 92697‐2025, USA, Fax: +1‐949‐824‐9920
| | - K. A. Woerpel
- Department of Chemistry, University of California, Irvine, California 92697‐2025, USA, Fax: +1‐949‐824‐9920
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28
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Tetrahedron reports on organic chemistry. Tetrahedron 2007. [DOI: 10.1016/s0040-4020(07)01371-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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29
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Tetrahedron reports on organic chemistry. Tetrahedron 2007. [DOI: 10.1016/s0040-4020(07)00834-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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30
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Tetrahedron reports on organic chemistry. Tetrahedron 2007. [DOI: 10.1016/s0040-4020(07)00205-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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31
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32
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Lectka T, Motherwell W. Tetrahedron reports on organic chemistry. Tetrahedron 2006. [DOI: 10.1016/s0040-4020(06)01801-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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33
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Lectka T, Motherwell W. Tetrahedron reports on organic chemistry. Tetrahedron 2006. [DOI: 10.1016/s0040-4020(06)00771-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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34
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Zora M. A comparison of the Cope rearrangements of cis-1,2-divinylcyclopropane, cis-2,3-divinylaziridine, cis-2,3-divinyloxirane, cis-2,3-divinylphosphirane, and cis-2,3-divinylthiirane: a DFT study. J Org Chem 2005; 70:6018-26. [PMID: 16018698 DOI: 10.1021/jo050711l] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Transition structures, energetics, and nucleus-independent chemical shifts (NICS) for Cope rearrangements of cis-2,3-divinylaziridine (1N), cis-2,3-divinyloxirane (1O), cis-2,3-divinylphosphirane (1P), and cis-2,3-divinylthiirane (1S), leading to 4,5-dihydro-1H-azepine (3N), 4,5-dihydrooxepine (3O), 4,5-dihydro-1H-phosphepine (3P), and 4,5-dihydrothiepine (3S), respectively, are reported at the (U)B3LYP/6-31G level and compared to those of cis-1,2-divinylcyclopropane (1C). The minimum energy path for all rearrangements proceeds through an endo-boatlike, aromatic transition structure. The predicted activation barriers increase in the order of 1C < 1N < 1O < 1P < 1S, which agrees qualitatively with the decreasing ring strain order of reference compounds (cyclopropane > aziridine > oxirane > phosphirane > thiirane). The exothermicities for these rearrangements decrease in the order of 1N > 1O > 1C > 1P > 1S. If the place of 1C in this sequence is ignored, the decreasing reaction exothermicity order correlates well with the increasing activation barrier order and with decreasing strain order of reference compounds. NICS values calculated for transition structures are typical of highly aromatic transition structures of thermally allowed pericyclic reactions.
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Affiliation(s)
- Metin Zora
- Department of Chemistry, Middle East Technical University, 06531 Ankara, Turkey.
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35
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Kagumba LC, Penelle J. Anionic Ring-opening Polymerization of Alkyl 1-Cyanocyclopropanecarboxylates. Macromolecules 2005. [DOI: 10.1021/ma0484025] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lawino C. Kagumba
- Department of Polymer Science and Engineering, University of Massachusetts, Amherst, Massachusetts 01003-4530
| | - Jacques Penelle
- Department of Polymer Science and Engineering, University of Massachusetts, Amherst, Massachusetts 01003-4530
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36
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Müller P, Mareda J. Steric Effects on Reaction Rates. Part IX. Force-Field Parameters for Bridgehead and Rigid Tertiary Carbenium Ions. Helv Chim Acta 2004. [DOI: 10.1002/hlca.19870700414] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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37
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Müller P, Mareda J, Milin D. Strain and structural effects on rates of formation and stability of tertiary carbenium ions in the light of molecular mechanics calculations. J PHYS ORG CHEM 2004. [DOI: 10.1002/poc.610080802] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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38
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Poon T, Sivaguru J, Franz R, Jockusch S, Martinez C, Washington I, Adam W, Inoue Y, Turro NJ. Temperature and Solvent Control of the Stereoselectivity in the Reactions of Singlet Oxygen with Oxazolidinone-Substituted Enecarbamates. J Am Chem Soc 2004; 126:10498-9. [PMID: 15327281 DOI: 10.1021/ja048438c] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Oxazolidinone-functionalized enecarbamates react stereoselectively with singlet oxygen to give methyldesoxybenzoin (MDB) in moderate to high enantiomeric excess. The stereochemical outcome depends on the E/Z substrate geometry, temperature, and solvent variables. The analysis of the differential activation parameters suggests a large contribution from the entropy term in determining the enantioselectivity. We demonstrate the utility of the temperature and solvent variables in determining the degree of the photochemical kinetic resolution of the enecarbamates; for example, in the photooxygenation at -70 degrees C in methanol, MDB may be obtained in methanol.
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Affiliation(s)
- Thomas Poon
- Joint Science Department, W.M. Keck Science Center, 925 North Mills Avenue, Claremont McKenna, Pitzer, and Scripps Colleges, Claremont, California 91711, USA
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39
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Posner PG, Motherwell PW. Tetrahedron reports on organic chemistry. Tetrahedron 2004. [DOI: 10.1016/s0040-4020(04)01396-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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40
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Tetrahedron reports on organic chemistry. Tetrahedron 2004. [DOI: 10.1016/s0040-4020(04)00315-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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41
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Rüchardt C, Beckhaus HD. Consequences of Strain for the Structure of Aliphatic Molecules. ACTA ACUST UNITED AC 2003. [DOI: 10.1002/anie.198505293] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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42
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Posner PG, Motherwell PW. Tetrahedron reports on organic chemistry. Tetrahedron 2003. [DOI: 10.1016/s0040-4020(03)01884-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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43
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Posner PG, Motherwell PW. Tetrahedron reports on organic chemistry. Tetrahedron 2003. [DOI: 10.1016/s0040-4020(03)01130-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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44
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Posner PG, Motherwell PW. Tetrahedron reports on organic chemistry. Tetrahedron 2003. [DOI: 10.1016/s0040-4020(03)00841-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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45
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Tetrahedron reports on organic chemistry. Tetrahedron 2003. [DOI: 10.1016/s0040-4020(03)00323-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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46
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Posner G, Motherwell W. Tetrahedron reports on organic chemistry. Tetrahedron 2002. [DOI: 10.1016/s0040-4020(02)01503-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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47
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Harger MJP. Acid Catalysed Reactions of Ω-Mercaptoalkyl-Phosphinic Anilides: Reluctance of the Thiol Group to Participate in Displacement of the Aniline Moiety. JOURNAL OF CHEMICAL RESEARCH 2000. [DOI: 10.3184/030823400103167363] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Acid catalysed cyclisation occurs readily with HO(CH2)n+3P(O)(NHPh)Ph (n = 0 or 1) in MeOH but only acyclic HS(CH2)n+3P(O)(OMe)Ph is obtained when HS(CH2)n+3P(O)(NHPh)Ph (n = 0 or 1) is treated with HCl in CDCl3 containing 1% MeOH; cyclisation can occur if MeOH is excluded completely but even the five-membered cyclic thiophosphinate 5 (n= 0) is not formed readily.
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48
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Lammertsma K, Wang B, Hung JT, Ehlers AW, Gray GM. Synthesis, Structure, Strain Energy, and Excess Strain of a Phospha[3]triangulane. J Am Chem Soc 1999. [DOI: 10.1021/ja9905896] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Koop Lammertsma
- Contribution from the Faculty of Chemistry, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands, and Department of Chemistry, University of Alabama at Birmingham, UAB Station, Birmingham, Alabama 35294-1240
| | - Bing Wang
- Contribution from the Faculty of Chemistry, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands, and Department of Chemistry, University of Alabama at Birmingham, UAB Station, Birmingham, Alabama 35294-1240
| | - Jui-Te Hung
- Contribution from the Faculty of Chemistry, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands, and Department of Chemistry, University of Alabama at Birmingham, UAB Station, Birmingham, Alabama 35294-1240
| | - Andreas W. Ehlers
- Contribution from the Faculty of Chemistry, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands, and Department of Chemistry, University of Alabama at Birmingham, UAB Station, Birmingham, Alabama 35294-1240
| | - Gary M. Gray
- Contribution from the Faculty of Chemistry, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands, and Department of Chemistry, University of Alabama at Birmingham, UAB Station, Birmingham, Alabama 35294-1240
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49
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Wilsey S, Dowd P, Houk KN. Effect of Alkyl Substituents and Ring Size on Alkoxy Radical Cleavage Reactions. J Org Chem 1999; 64:8801-8811. [PMID: 11674782 DOI: 10.1021/jo990652+] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The alpha-cleavage ring-opening reactions of a series of acyclic and cyclic alkoxy radicals are examined computationally with CASSCF/6-31G, UHF/6-31G, and UB3LYP/6-31G methods, to explain the anomalous results obtained by Zhang and Dowd (Tetrahedron 1993, 49, 1965): tricyclic alkoxy radicals were found to cleave to give the less-stable products in several cases; even allylic stabilization of the radical formed by cleavage does not influence the direction of cleavage. The source of this kinetic preference is identified as arising from two factors: (i) through-bond interactions significantly slow the rate of bond cleavage in fused four-membered rings relative to exocyclic cleavage of four-membered rings, and (ii) allylic stabilization is not effective in the early transition state of alkoxy radical cleavage in these strained systems. The relationship between activation energies of cleavage and the energy of the reaction is explored for a variety of cyclic and acyclic alkoxy radicals. Benson's observation that the ease of cleavage is related to both the heat of reaction and the ionization potential of the radical formed (Int. J. Chem. Kinet. 1981, 13, 833) is confirmed and extended to more examples.
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Affiliation(s)
- Sarah Wilsey
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California, 90095-1569, and Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
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50
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Cao W, Erden I, Grow RH, Keeffe JR, Song J, Trudell MB, Wadsworth TL, Xu FP, Zheng JB. Article. CAN J CHEM 1999. [DOI: 10.1139/v99-061] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Equilibrium and rate constants have been determined for the acid-catalyzed heterolysis of two alcohols, 9-xanthydrol and p-anisyldiphenylmethanol, and two sulfides, (9-xanthyl) methyl sulfide and (7-tropyl) methyl sulfide. These data together with literature information are compared with rate constants for acid-catalyzed C-C heterolysis of several (9-xanthyl) compounds, (7-tropyl) compounds, a set of 3-arylcyclobutanones, and two 2-arylnitrocyclopropanes, all of which fragment to carbocations plus a carbon-centered nucleofuge. The fragmentation mechanisms are shown to be A1 or A1(ion pair) except for the 2-arylnitrocyclopropanes which cleave in trifluoroacetic acid by a concerted mechanism. Rate comparisons among several unstrained substrate sets indicate that O-centered nucleofuges undergo acid-catalyzed heterolysis ca. 103-104 faster than S-centered nucleofuges and ca. 109-1014 faster than the C-centered nucleofuges used here. Factors assisting C-C heterolysis (and their effectiveness) include the acidity of the medium (strong); the basicity and nucleofugality of the nucleofuge (moderate); the stability of the electrofugic carbocation (strong); and relief of ring strain (enormous). Compared with acyclic cleavages, rate accelerations worth ca. 15 kcal/mol (for cyclobutanones) and ca. 27 kcal/mol (for nitrocyclopropanes) are found. These effects are discussed in terms of transition-state structure, aided by computational evidence.Key words: C-C heterolysis, fragmentation, acid catalysis, carbocation, ring strain.
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