Theoretical study of the ground and excited states of 1-methylamideanthraquinone and its complex with fluoride anion

We have performed a series of calculations using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) for 1-methylamideanthraquinone (MAAQ). In the S0 state of MAAQ, amide group is coplanar with anthraquinone, and an intramolecular hydrogen bond [Formula: see text] is formed. The [Formula: see text] transition has an intramolecular charge transfer character. Two stable structures (planar nMAAQ and twisted tMAAQ) have been obtained in the S1 state of MAAQ. Thereinto, nMAAQ is lower by 0.105[Formula: see text]eV than tMAAQ in energy, so nMAAQ is the dominant conformation in the S1 state of MAAQ and the emission spectra of tMAAQ cannot be observed in the solution of MAAQ. Excited state intramolecular proton transfer (ESIPT) between C[Formula: see text]O and N–H was not observed in the S1 state of MAAQ. Upon addition of fluoride anion, only twisted conformations were obtained in both S0 and S1 states of MAAQ-F[Formula: see text]. An intermolecular hydrogen bond [Formula: see text] is formed in the S0 state, and intermolecular proton transfer happens in the S1 state for MAAQ-F[Formula: see text].

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An X-ray crystallographic and density functional theory study of (3Z)-4-(5-ethylsulfonyl-2-hydroxyanilino)pent-3-en-2-one and (3Z)-4-(5-tert-butyl-2-hydroxyanilino)pent-3-en-2-one

Acta Crystallographica Section C Crystal Structure Communications ◽

10.1107/s0108270113002369 ◽

2013 ◽

Vol 69 (3) ◽

pp. 258-262

Author(s):

Kate J. Akerman ◽

Orde Q. Munro

Keyword(s):

Density Functional Theory ◽

Hydrogen Bond ◽

Intramolecular Hydrogen Bond ◽

Density Functional ◽

Intermolecular Hydrogen Bond ◽

Functional Theory ◽

One Dimensional ◽

X Ray ◽

Intramolecular Hydrogen ◽

Hydrogen Bonded

The Schiff base enaminones (3Z)-4-(5-ethylsulfonyl-2-hydroxyanilino)pent-3-en-2-one, C13H17NO4S, (I), and (3Z)-4-(5-tert-butyl-2-hydroxyanilino)pent-3-en-2-one, C15H21NO2, (II), were studied by X-ray crystallography and density functional theory (DFT). Although the keto tautomer of these compounds is dominant, the O=C—C=C—N bond lengths are consistent with some electron delocalization and partial enol character. Both (I) and (II) are nonplanar, with the amino–phenol group canted relative to the rest of the molecule; the twist about the N(enamine)—C(aryl) bond leads to dihedral angles of 40.5 (2) and −116.7 (1)° for (I) and (II), respectively. Compound (I) has a bifurcated intramolecular hydrogen bond between the N—H group and the flanking carbonyl and hydroxy O atoms, as well as an intermolecular hydrogen bond, leading to an infinite one-dimensional hydrogen-bonded chain. Compound (II) has one intramolecular hydrogen bond and one intermolecular C=O...H—O hydrogen bond, and consequently also forms a one-dimensional hydrogen-bonded chain. The DFT-calculated structures [in vacuo, B3LYP/6-311G(d,p) level] for the keto tautomers compare favourably with the X-ray crystal structures of (I) and (II), confirming the dominance of the keto tautomer. The simulations indicate that the keto tautomers are 20.55 and 18.86 kJ mol−1lower in energy than the enol tautomers for (I) and (II), respectively.

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Time-Dependent Density Functional Theory Investigation of Excited State Intramolecular Proton Transfer in Tris(2-hydroxyphenyl)triazasumanene

The Journal of Physical Chemistry A ◽

10.1021/acs.jpca.9b10340 ◽

2020 ◽

Vol 124 (7) ◽

pp. 1227-1234 ◽

Cited By ~ 4

Author(s):

Sitanan Sartyoungkul ◽

Masahiro Ehara ◽

Hidehiro Sakurai

Keyword(s):

Density Functional Theory ◽

Excited State ◽

Proton Transfer ◽

Density Functional ◽

Intramolecular Proton Transfer ◽

Time Dependent ◽

Functional Theory ◽

Dependent Density

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An analogy study on ESIPT reaction for 3BHC sensor between polar DMF and nonpolar toluene

Canadian Journal of Chemistry ◽

10.1139/cjc-2017-0463 ◽

2017 ◽

Vol 95 (12) ◽

pp. 1303-1307

Author(s):

Dapeng Yang ◽

Min Jia ◽

Jingyuan Wu ◽

Xiaoyan Song ◽

Qiaoli Zhang

Keyword(s):

Excited State ◽

Density Functional ◽

Emission Spectra ◽

Dft Method ◽

Intramolecular Proton Transfer ◽

Nonpolar Solvent ◽

State Behavior ◽

Functional Theory ◽

Td Dft ◽

Intramolecular Hydrogen

A comparison about excited state intramolecular proton transfer (ESIPT) mechanism of a new sensor 3-(1,3-benzothiazol-2-yl)-2-hydroxynaphthalene-1-carbaldehyde (3BHC) in polar solvent dimethylformamide (DMF) and nonpolar solvent toluene have been investigated within the framework of the time-dependent density functional theory (TD-DFT) method. The reproduced previous experimental absorption and emission spectra via our calculations reveals the reasonability of the DFT and TD-DFT theoretical level. The staple bond lengths, bond angles, and corresponding infrared vibrational spectra demonstrate that the intramolecular hydrogen bond of 3BHC should be strengthened in both polar DMF and nonpolar toluene. Two kinds of ESIPT mechanisms for different solvents have been put forward; there is a low potential barrier in the ESIPT process in the DMF solvent, whereas there is almost a nonbarrier for the ESIPT process in the toluene solvent. Hence, we could conclude that the ESIPT process of 3BHC sensor is more likely to occur in the nonpolar solvent upon the photoexcitation, based on which, the excited state behavior of 3BHC could be controlled.

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Competitive excited-state single or double proton transfer mechanisms for bis-2,5-(2-benzoxazolyl)-hydroquinone and its derivatives

Physical Chemistry Chemical Physics ◽

10.1039/c4cp05651e ◽

2015 ◽

Vol 17 (18) ◽

pp. 11990-11999 ◽

Cited By ~ 176

Author(s):

Jinfeng Zhao ◽

Junsheng Chen ◽

Jianyong Liu ◽

Mark R. Hoffmann

Keyword(s):

Density Functional Theory ◽

Excited State ◽

Proton Transfer ◽

Density Functional ◽

Intramolecular Proton Transfer ◽

Time Dependent ◽

Functional Theory ◽

Double Proton Transfer ◽

Transfer Mechanisms ◽

Dependent Density

The excited state intramolecular proton transfer (ESIPT) mechanism of HBO, BBHQ and DHBO have been investigated using time-dependent density functional theory (TDDFT).

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Caryolene-forming carbocation rearrangements

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.9.37 ◽

2013 ◽

Vol 9 ◽

pp. 323-331 ◽

Cited By ~ 21

Author(s):

Quynh Nhu N Nguyen ◽

Dean J Tantillo

Keyword(s):

Density Functional Theory ◽

Proton Transfer ◽

Energy Barrier ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Intramolecular Proton Transfer ◽

The Other ◽

Orbital Symmetry ◽

Functional Theory ◽

Biosynthetic Precursor

Density functional theory calculations on mechanisms of the formation of caryolene, a putative biosynthetic precursor to caryol-1(11)-en-10-ol, reveal two mechanisms for caryolene formation: one involves a base-catalyzed deprotonation/reprotonation sequence and tertiary carbocation minimum, whereas the other (with a higher energy barrier) involves intramolecular proton transfer and the generation of a secondary carbocation minimum and a hydrogen-bridged minimum. Both mechanisms are predicted to involve concerted suprafacial/suprafacial [2 + 2] cycloadditions, whose asynchronicity allows them to avoid the constraints of orbital symmetry.

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