Results 21 to 30 of about 1,579 (190)
How do the Hückel and Baird Rules Fade away in Annulenes?
Molecules, 2020 Two of the most popular rules to characterize the aromaticity of molecules are those due to Hückel and Baird, which govern the aromaticity of singlet and triplet states.
Irene Casademont-Reig +3 more
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Molecules, 2020 Density functional calculations and up to five different basis sets have been applied to the exploration of the structural, enthalpy and free energy changes upon conversion of the azepine to the corresponding N-oxide.
René Fournier +5 more
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ChemistryOpen, 2023 The construction of 1,2‐position‐connected azulene oligomers was achieved. In the crystal packing structure of the terazulene, two molecules of (Ra)‐ and (Sa)‐configurations formed a pair.
Prof. Dr. Takahiro Tsuchiya +2 more
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Molecules, 2023 We utilized a cycloaromatization reaction driven by relief of excited state antiaromaticity to photouncage aldehydes and ketones. We developed several synthetic routes towards the synthesis of photocaged carbonyls as allylically substituted 3-(2 ...
Adam Campbell +2 more
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Norcorrole: Aromaticity and Antiaromaticity in Contest [PDF]
Organic Letters, 2020 Magnetic shielding studies demonstrate that nickel norcorrole (NiNc) and norcorrole (H2Nc) provide unusual examples of stable molecules with high antagonistic levels of antiaromaticity and aromaticity: Both incorporate an antiaromatic "core", a 14-membered cyclic conjugated subsystem with 16 π electrons, surrounded by an aromatic "halo" in the form of ...
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Cyclobutadiene: The Antiaromatic Paradigm? [PDF]
ChemInform, 2006 AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
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Relief of excited-state antiaromaticity enables the smallest red emitter
Nature Communications, 2021 Commonly, large π-conjugated systems facilitate low-energy electronic transitions. Here, the authors demonstrate that the relief of excited-state antiaromaticity of the benzene core leads to large Stokes shifts, and allows the construction of emitters ...
Heechan Kim +5 more
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The Silacyclobutene Ring: An Indicator of Triplet State Baird-Aromaticity
Inorganics, 2017 Baird’s rule tells that the electron counts for aromaticity and antiaromaticity in the first ππ* triplet and singlet excited states (T1 and S1) are opposite to those in the ground state (S0). Our hypothesis is that a silacyclobutene (SCB) ring fused with
Rabia Ayub +2 more
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Advanced Science, 2020 Although polycyclic conjugated hydrocarbons (PCHs) and their analogues have gained great progress in the fields of organic photoelectronic materials, the in‐depth study on present PCHs is still limited to hexacene or below because longer PCHs are ...
Wangqiao Chen +4 more
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Angewandte Chemie, EarlyView.Here we report two nonalternant polycyclic aromatic hydrocarbons (PAH) (1 and 2), which contain two and four consecutive pentagons, respectively. Under acidic conditions, 1 and 2 dimerize to afford the axially chiral dimers AC1 and AC2. The central azulene moiety in both 2 and AC2 shows an unusually short transannular bond of 1.366 Å.
Chang Wang +3 more
wiley +2 more sources