Article
Chemistry, Organic
Takeo Sakai, Tomoki Furuhata, Kota Hosoe, Kaho Umemura, Yuji Mori
Summary: A novel cascade reaction involving alkylation, cyclization, isomerization, and 3-aza-Cope rearrangement was developed. The chiral centers of the starting piperidines were transferred to the bicyclic enamine products, and a wide range of electron-withdrawing groups on the alkyne moieties were tolerated. The resulting bicyclic enamines underwent cyclization mediated by trifluoroacetic acid (TFA) to produce tricyclic amines with tetrasubstituted carbons.
Article
Chemistry, Organic
D. Magoo, Komal Aggarwal, Shruti Gupta, Kalawati Meena
Summary: A diverse library of nitrogen containing heterocyclic compounds can be synthesized through the versatility of enamine intermediates and multicomponent reactions.
Review
Chemistry, Multidisciplinary
Hsuan-Hung Liao, Shinje Minoza, Shao-Chi Lee, Magnus Rueping
Summary: This review presents the progress of aza-ortho-quinone methide (aza-o-QM) chemistry in the past few decades. Various catalytic strategies using transition metals and organocatalysts are discussed for controlling aza-o-QM intermediates, leading to the synthesis of complex molecular scaffolds.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Organic
Ricardo Meyrelles, Yener Fetisleam, Boris Maryasin
Summary: This study presents a computational analysis of the aza-Cope rearrangement, which leads to angularly substituted 1-azabicyclic ring systems. The calculations estimate the probability of proton transfer between reaction intermediates and solvents, explain the observed reaction selectivity, and propose new potentially more efficient systems for further in vitro and in vivo investigations.
Article
Chemistry, Physical
Sahand Emamian, Kendra A. Ireland, Vatsal Purohit, Kirklin L. McWhorter, Olga Maximova, Winter Allen, Scott Jensen, Diego M. Casa, Yulia Pushkar, Katherine M. Davis
Summary: The study demonstrates the feasibility of collecting X-ray emission spectra of metalloenzyme crystals to elucidate structural rearrangements and active site conformation information in metalloenzyme mechanisms.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Physical
Kaito Takahashi
Summary: This article investigates the UV spectra of Criegee intermediates and uses wave packet propagation to simulate the spectra of different Criegee intermediates. The study finds that multireference methods can better predict experimental results, while single reference methods tend to give narrower peaks. Testing various approximated potential energy curves and transition moment functions also confirms the validity of the Gaussian approximation.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Chemistry, Multidisciplinary
Jyothish Joy, Daniel H. Ess
Summary: The reaction mechanism between non-heme Fe-oxo complexes and alkane C-H bonds involves a hydrogen atom transfer reaction step with a radical pair intermediate. Density functional theory-based quasiclassical direct dynamics trajectories reveal that the post-HAT reaction dynamics and selectivity are determined by dynamic effects. These trajectories provide a new understanding of the reaction pathway selectivity for non-heme Fe-oxo-mediated C-H functionalization reactions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Physical
Carlos Bistafa, Yukichi Kitamura, Masataka Nagaoka
Summary: We propose a self-contained theoretical methodology to predict the pH effects on the molecular electronic spectra in aqueous solution. By combining the configuration-selection constant-pH simulation method with quantum mechanics/molecular mechanics method, we can obtain the theoretical description of the pH dependent electronic spectra.
CHEMICAL PHYSICS LETTERS
(2022)
Article
Chemistry, Physical
Pieter Cnudde, Michel Waroquier, Veronique Van Speybroeck
Summary: The influence of pore topology and acid strength on the adsorption of (iso)butene in Bronsted acid zeolites has been studied using calculations and simulations. The adsorbed intermediates - physisorbed alkene, chemisorbed carbenium ion, and alkoxide - were evaluated for different zeolite topologies and acid site strengths. The stabilization of the carbenium ion depends on zeolite confinement and acid site strength, while alkoxides are not found at high temperature. The adsorption energies and protonation barriers can be predicted using universal descriptors such as dispersion component and ammonia adsorption energy.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Physical
Johanna Rogvall, Roshan Singh, Morgane Vacher, Marcus Lundberg
Summary: Photochemistry and photophysics processes involve structures far from equilibrium, with strong coupling between nuclear and electronic degrees of freedom. K beta X-ray emission spectroscopy (XES) is sensitive to electronic structure and can be used as a probe for structural dynamics. Simulations of spectral changes in an iron photosensitizer [Fe-II(bmip)(2)](2+) showed a blue-shift with increasing metal-ligand distance, indicating the presence of coherent wavepacket dynamics. This study provides insights for designing and interpreting XES probes in photocatalysis.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
A. A. Kamneva, D. V. Yashunsky, A. G. Gerbst, N. E. Nifantiev
Summary: The reactions between 2-O-trifluoromethanesulfonate & beta;-D-glucopyranoside derivatives and the azide anion in the synthesis of oligosaccharides related to Haemophilus influenzae type e capsular polysaccharide fragments were studied. These reactions resulted in products of nucleophilic substitution and rearrangement, accompanied by contraction of a 6-membered pyranose ring to a 5-membered ring through (O5-C2)-cyclization. The formation of these products was explained for the first time using quantum mechanical calculations.
Article
Optics
Cunqiang Wu, Runxia Zhao, Denghong Zhang, Mingwu Zhang, Yingli Xue, Deyang Yu, Chenzhong Dong, Xiaobin Ding
Summary: The excitation energies of Be-like ions (4≤Z≤74) in the doubly excited state 1s(2)2p(2) and doubly core-excited state 2s2p3 were calculated using the multi-configuration Dirac-Hartree-Fock method. The contributions of relativistic effects, Breit interaction, and QED effects to the excitation energies were analyzed. The results provide insights for future experimental and theoretical work.
EUROPEAN PHYSICAL JOURNAL D
(2023)
Article
Chemistry, Medicinal
Marta S. Andrade, Vanessa S. Silva, Ana M. Lourenco, Ana M. Lobo, Henry S. Rzepa
Article
Chemistry, Multidisciplinary
D. Christopher Braddock, Areeb Mahtey, Henry S. Rzepa, Andrew J. P. White
CHEMICAL COMMUNICATIONS
(2016)
Correction
Chemistry, Medicinal
M. S. Andrade, V. S. Silva, A. M. Lourenco, A. M. Lobo, H. S. Rzepa
Article
Biophysics
Diana Silva, Luis F. V. Pinto, Dimitriya Bozukova, Luis F. Santos, Ana Paula Serro, Benilde Saramago
COLLOIDS AND SURFACES B-BIOINTERFACES
(2016)
Article
Chemistry, Organic
Hossay Abas, Sean M. Linsdall, Mathias Mamboury, Henry S. Rzepa, Alan C. Spivey
Article
Chemistry, Multidisciplinary
Matthew J. Harvey, Andrew McLean, Henry S. Rzepa
JOURNAL OF CHEMINFORMATICS
(2017)
Article
Chemistry, Multidisciplinary
Debdeep Mandal, Debabrata Dhara, Avijit Maiti, Lukas Klemmer, Volker Huch, Michael Zimmer, Henry S. Rzepa, David Scheschkewitz, Anukul Jana
CHEMISTRY-A EUROPEAN JOURNAL
(2018)
Article
Chemistry, Medicinal
Daniela Peixoto, Elisabete P. Ferreira, Ana M. Lourenco, Jordan L. Johnson, Ana M. Lobo, Prasad L. Polavarapu
Article
Chemistry, Medicinal
Francisco Avelelas, Andre Horta, Luis F. V. Pinto, Sonia Cotrim Marques, Paulo Marques Nunes, Rui Pedrosa, Sergio Miguel Leandro
Article
Chemistry, Multidisciplinary
Carina I. C. Crucho, Joao Avo, Ana M. Diniz, Mario J. S. Gomes
JOURNAL OF CHEMICAL EDUCATION
(2020)
Article
Biochemical Research Methods
Yuri Binev, Daniela Peixoto, Florbela Pereira, Ian Rodrigues, Sofia Cavaco, Ana M. Lobo, Joao Aires-de-Sousa
Article
Chemistry, Physical
P. R. Prezas, B. M. G. Melo, L. C. Costa, M. A. Valente, M. C. Lanca, J. M. G. Ventura, L. F. V. Pinto, M. P. F. Graca
APPLIED SURFACE SCIENCE
(2017)
Article
Chemistry, Multidisciplinary
James I. Murray, Nils J. Floden, Adriano Bauer, Nico D. Fessner, Daniel L. Dunklemann, Opetoritse Bob-Egbe, Henry S. Rzepa, Thomas Burgi, Jeffery Richardson, Alan C. Spivey
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2017)
Article
Chemistry, Organic
Geeta Devi Yadav, Pooja Chaudhary, Balaram Pani, Surendra Singh
Summary: Chiral transition metal complexes with privileged ligands are efficient catalysts for various asymmetric organic transformations. Transition metal complexes of C1-symmetric pyrrolidine-based ligands have been widely used in asymmetric organic reactions. However, a comprehensive review article on the transition metal complexes of chiral C1-symmetric pyrrolidine-based ligands derived from (L)-proline has not been published.
TETRAHEDRON LETTERS
(2024)
