Determination of Hammett Sigma Constants by Intramolecular Hydrogen Bonding [PDF]
Nature, 1958 THE extensive literature that exists concerning Hammett's σ-constants has been subjected to several recent reviews, including a compilation and examination of available data1, a discussion of the significance and limitations of the concepts involved2, and an attempt to deduce best values and probable errors for the σ-values3.
A. T. SHULGIN, A. W. BAKER
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Leveraging graph neural networks to predict Hammett’s constants for benzoic acid derivatives
Artificial Intelligence ChemistryThe Hammett constants, σm and σp, reflect the electron-withdrawing and electron-donating abilities of substituents on aromatic compounds, and have been successfully used in various structure-activity relationship studies.
Vaneet Saini, Ranjeet Kumar
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Exchange Speed of Four-Component Nanorotors Correlates with Hammett Substituent Constants
Chemistry, 2021 Three distinct four-component supramolecular nanorotors were prepared, using, for the first time, bipyridine instead of phenanthroline stations in the stator.
Yi-Fan Li +4 more
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Gas phase hydration, bond dissociation enthalpies, and acidity of aldehydes: A CBS-Q//B3, G4MP2, and G4 theoretical study of substituent effects [PDF]
, 2010 CBS-Q//B3, G4MP2, and G4 composite method calculations were used to estimate gas phase standard state (298.15 K, 1 atm) free energies of hydration (Δ~hydr~G°~(g)~), hydration equilibrium constants (log K~hydr,(g)~), bond dissociation ...
Kaya Forest, Sierra Rayne
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Excited state substituent constants: to Hammett or not? [PDF]
Structural Chemistry, 2011 In this study, an answer has been sought to several questions: Can substituents’ impact on the electronic properties of molecules in the excited singlet states be summed up by a set of substituent constants? Are the well known, ground state Hammett σ constants practical for this purpose? To answer these questions, the potentials and charges on atoms of
Sadlej-Sosnowska, Nina, Kijak, Michał
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Mechanism of C−F Reductive Elimination from Palladium(IV) Fluorides [PDF]
, 2010 The first systematic mechanism study of C−F reductive elimination from a transition metal complex is described. C−F bond formation from three different Pd(IV) fluoride complexes was mechanistically evaluated.
Benitez, Diego +6 more
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Selective Pd-Catalyzed Oxidative Coupling of Anilides with Olefins through C-H Bond Activation at Room Temperature [PDF]
, 2002 Kinetic Alfv\'en waves represent an important subject in space plasma physics, since they are thought to play a crucial role in the development of the turbulent energy cascade in the solar wind plasma at short wavelengths (of the order of the proton ...
Boele, Maarten D.K., +5 more
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Molecules, 2016 The relationship between the electrophilicity ω index and the Hammett constant σp has been studied for the [2+3] cycloaddition reactions of a series of para-substituted phenyl azides towards para-substituted phenyl alkynes. The electrophilicity ω index—a
Hicham Ben El Ayouchia +5 more
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The substituent effects on the 13c chemical shifts of the azomethine carbon atom of n-(phenyl substituted) salycilaldimines [PDF]
Journal of the Serbian Chemical Society, 2012 The Hammett correlations between 13C-NMR chemical shifts of the azomethine carbon atom and the corresponding substituent constants for thirtheen Schiff bases were established.
Drmanić Saša Ž. +3 more
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تعیین ثوابت تأین بعض قواعد شف المشتقة من الفانلین والأنلین ومعوضاته بالطریقة التسحیحیة الطیفیة (تطبیق علاقة هامت) [PDF]
مجلة ابحاث كلية التربية الاساسية, 2023 شتمل البحث على تحضیر تسع مرکبات من قواعد شف من تفاعل التکاثف لالدیهاید الفانلین مع معوضات الانلین، إن ثوابت التأین لـ 3-میثوکسی-4-هیدروکسی بنزالدینیلین ومعوضاته بمجموعة النایترو بموقع اورثو ومیتا ومجموعتی المثیل والکلور فی موقع اورثو ومیتا وبارا تم ...
رواء داؤد
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