Article
Chemistry, Multidisciplinary
Sheng Zhang, Yating Liang, Ke Liu, Xuan Zhan, Weigang Fan, Man-Bo Li, Michael Findlater
Summary: This study presents a strategy using hydrogen evolution reaction (HER) to generate carbanions from weakly acidic sp(3) C-H bonds. This approach allows for selective functionalization of C-H bonds without the use of strong bases or complicated procedures, enabling mild and efficient allylation and allenylation reactions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Vijayanath Elakkat, Eskedar Tessema, Chia-Her Lin, Xiaoping Wang, Huan-Cheng Chang, You-Ning Zheng, Yu-Cheng Huang, Zhong-Yun Gurumallappa, Zhong-Yun Zhang, Ka Long A. Chan, Hening A. S. Rahayu, Joseph S. Francisco, Norman Lu
Summary: To understand the effect of non-covalent weak interactions on molecules, we investigated different types of weak interactions in fluorinated chiral zinc complexes, including improper H-bonding, tetrel bonds, and halogen bonds. High resolution neutron diffraction studies revealed elongation and shortening of the methylene carbon-hydrogen bond due to tetrel bonds and improper H-bond interactions, respectively. We demonstrated how multiple weak interactions can cumulatively affect the C-H bond and offset its elongation through formation of an improper H-bond. Non-covalent interaction and electrostatic potential analysis investigations confirmed the nature of these interactions using density functional theory (DFT) and related calculations.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Fang Wang, Jiaming Chen, Xiaoqi Jia, Dailin Zhuang, Zhenyang Wan, Lifang Ma, Ziyuan Li
Summary: A remote directing group-enabled radical relay strategy for benzylic direct C(sp3)-H alkoxylation with alcohols at room temperature is developed, which achieves satisfactory site-selectivity, chemoselectivity, and reaction scope under simple and mild conditions without the need for ligands or additives.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Subham Ranjan, Ryota Morioka, Meguya Ryu, Junko Morikawa, Satoshi Takamizawa
Summary: This study investigates the mechanical deformation in two cocrystals and reveals the relationship between structure and properties, providing guidance for the design of organic crystals with superelastic or ferroelastic properties based on rational selection of intermolecular interactions.
Article
Chemistry, Organic
David F. Fernandez, Maria Gonzalez-Esguevillas, Sebastian Keess, Felix Schafer, Jens Mohr, Andre Shavnya, Thomas Knauber, David C. Blakemore, David W. C. MacMillan
Summary: We present a general approach to synthesis of diversified libraries featuring aliphatic core rings via photoredox catalysis under mild conditions.
Article
Chemistry, Organic
A. Young Ji, Annaram Thirupathi, Joon Young Hwang, Yuri Kim, Gyuri Han, Kwang-Hyun Ahn, Kyungtae Kang, Eun Joo Kang
Summary: The Fe-III(phen)(3) catalysis of the benzylic C(sp(3))-H azidation of indoles has been studied. The Fe(III) complex can selectively oxidize indoles to form arene radical cations, which are transformed into benzylic C(sp(3)) radical intermediates. This strategy exhibits a difference in reactivity between N-heteroarenes and benzene, which is difficult to achieve via direct hydrogen abstraction approaches. Various biorelevant azide precursors were constructed, highlighting the utility of this mild first-row transition-metal catalyst system.
Article
Chemistry, Organic
A. Young Ji, Annaram Thirupathi, Joon Young Hwang, Yuri Kim, Gyuri Han, Kwang-Hyun Ahn, Kyungtae Kang, Eun Joo Kang
Summary: The FeIII(phen)3 catalysis of benzylic C(sp3)-H azidation of indoles was studied. The Fe(III) complex can selectively oxidize indoles to form arene radical cations, which further transform into benzylic C(sp3) radical intermediates. This strategy exhibits a difference in reactivity between N-heteroarenes and benzene, which is difficult to achieve via direct hydrogen abstraction approaches. Various biorelevant azide precursors were synthesized, demonstrating the utility of this mild first-row transition-metal catalyst system.
Article
Chemistry, Organic
Javeed Ahmad Tali, Ravi Shankar
Summary: Here, we report an unprecedented protocol using ruthenium-catalyzed annulation for the synthesis of 6H-chromeno[4 ',3 ':4,5]imidazo[1,2-a]pyridin-6-one, and a new method for intramolecular chelation-assisted C-H activation to produce functionalized 2-(3-formylimidazo[1,2-a]pyridin-2-yl)phenyl acetate. Furthermore, a one-pot approach using ruthenium catalysis and formic acid has been developed for the gram-scale synthesis of bis(2-phenylimidazo[1,2-a]pyridin-3yl)methane (BIP) and the late-stage functionalization of zolimidine, a marketed drug, with good yield.
Article
Chemistry, Multidisciplinary
Mao Suzuki, Masahiro Terada, Itaru Nakamura
Summary: The [1,3]-nitrogen rearrangement reactions of O-aryl ketoximes were promoted by N-heterocyclic carbene (NHC)-copper catalysts and BF3 center dot OEt2 as an additive, affording ortho-aminophenol derivatives in good yields. The reaction of substrates with electron-withdrawing substituents on the phenol moiety are accelerated by adding silver salt and modifying the substituent at the nitrogen atom. Density functional theory calculations suggest that the rate-determining step of this reaction is the oxidative addition of the N-O bond of the substrate to the copper catalyst. The negative rho values of the substituent at both the oxime carbon and phenoxy group indicate that the donation of electrons by the oxygen and nitrogen atoms accelerates the oxidative addition.
Article
Chemistry, Physical
Taro Udagawa, Amane Kinoshita, Kazuaki Kuwahata, Masanori Tachikawa
Summary: This study investigates the nuclear quantum effects (NQEs) and thermal effects in dihydrogen bond (DHB) complexes through calculations and simulations. It is found that the formation of DHB complexes suppresses quantum fluctuations in the perpendicular direction, but slightly enhances it in the parallel direction.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Mariusz Michalczyk, Wiktor Zierkiewicz, Steve Scheiner
Summary: The possibility of two Lewis bases sharing a single halogen atom within the context of a bifurcated halogen bond (XB) is explored using a detailed examination of the Cambridge Structural Database (CSD). The study reveals that less than 2% of the geometries fitting the definition of an XB are bifurcated, with a preference for I over Br, which tends to form monofurcated bonds. The conversion from monofurcated to bifurcated bonds is associated with fewer short contact distances and a trend towards lesser linearity, with the two XB lengths and angles being somewhat symmetrical. Quantum calculations of model systems confirm the observed patterns in crystals and suggest that the negative cooperativity within a bifurcated XB weakens and lengthens each individual bond.
CRYSTAL GROWTH & DESIGN
(2022)
Article
Chemistry, Multidisciplinary
Tobias Pinkert, Mowpriya Das, Malte L. Schrader, Frank Glorius
Summary: This study describes the formation of quaternary carbon centers with excellent diastereoselectivity via a strain-release protocol, involving Cp*Rh(III)-catalyzed C-H activation to generate an organometallic species for coupling with strained bicyclobutanes and a prochiral carbon electrophile. The method demonstrates the broad potential of BCBs in transition metal catalysis and exhibits ample functional group tolerance, with products convertible into valuable alpha-quaternary beta-lactones. Preliminary mechanistic investigations suggest a twofold C-C bond cleavage sequence involving sigma-bond insertion and beta-carbon elimination.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Multidisciplinary Sciences
Ken Chen, Qingrui Zeng, Longhuan Xie, Zisheng Xue, Jianbo Wang, Yan Xu
Summary: In this study, a photocatalytic reversible C-H sampling reaction was developed to achieve the translocation of cyano groups in nitriles. This reaction enables the direct exchange between a cyano group and an unactivated C-H bond, offering a selective and valuable method for the synthesis of unconventional C-H derivatives and building blocks of bioactive molecules.
Article
Chemistry, Multidisciplinary
Zhuang Wang, Kaikai Niu, Yuxiu Liu, Hongjian Song, Qingmin Wang
Summary: A mild and convenient protocol for the synthesis of alpha-alkoxy isochroman derivatives has been reported in this study. The electrochemical alpha-C(sp(3))-H/O-H cross-coupling reactions of isochromans and alcohols in the presence of benzoic acid were used, which facilitated the electro-oxidation process and increased the product yield. The desired coupling products were obtained in moderate to high yields.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Hairong Lyu, Zuowei Xie
Summary: A unique approach to vertex-selective catalytic B-H amination has been developed, allowing the reaction to occur at either the B(3)- or B(4)-position in o-carboranes. By using different transition metal catalysts, the dehydrogenative BH/NH cross-coupling of o-carboranes and free amines has been achieved, resulting in a wide variety of B(3)- or B(4)-aminated o-carboranes with high regioselectivity.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Rebecca F. Alford, Andrew Leaver-Fay, Jeliazko R. Jeliazkov, Matthew J. O'Meara, Frank P. DiMaio, Hahnbeom Park, Maxim V. Shapovalov, P. Douglas Renfrew, Vikram K. Mulligan, Kalli Kappel, Jason W. Labonte, Michael S. Pacella, Richard Bonneau, Philip Bradley, Roland L. Dunbrack, Rhiju Das, David Baker, Brian Kuhlman, Tanja Kortemme, Jeffrey J. Gray
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2017)
Article
Biochemistry & Molecular Biology
Jiayi Dou, Lindsey Doyle, Per Jr. Greisen, Alberto Schena, Hahnbeom Park, Kai Johnsson, Barry L. Stoddard, David Baker
Article
Biochemistry & Molecular Biology
Hahnbeom Park, David E. Kim, Sergey Ovchinnikov, David Baker, Frank DiMaio
PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS
(2018)
Article
Biochemistry & Molecular Biology
Sergey Ovchinnikov, Hahnbeom Park, David E. Kim, Frank DiMaio, David Baker
PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS
(2018)
Article
Multidisciplinary Sciences
Sergey Ovchinnikov, Hahnbeom Park, Neha Varghese, Po-Ssu Huang, Georgios A. Pavlopoulos, David E. Kim, Hetunandan Kamisetty, Nikos C. Kyrpides, David Baker
Article
Chemistry, Medicinal
Jonghun Won, Gyu Rie Lee, Hahnbeom Park, Chaok Seok
JOURNAL OF CHEMICAL INFORMATION AND MODELING
(2018)
Article
Multidisciplinary Sciences
Hahnbeom Park, Sergey Ovchinnikov, David E. Kim, Frank DiMaio, David Baker
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2018)
Article
Multidisciplinary Sciences
Jiayi Dou, Anastassia A. Vorobieva, William Sheffler, Lindsey A. Doyle, Hahnbeom Park, Matthew J. Bick, Binchen Mao, Glenna W. Foight, Min Yen Lee, Lauren A. Gagnon, Lauren Carter, Banumathi Sankaran, Sergey Ovchinnikov, Enrique Marcos, Po-Ssu Huang, Joshua C. Vaughan, Barry L. Stoddard, David Baker
Article
Biochemistry & Molecular Biology
Hahnbeom Park, Gyu Rie Lee, David E. Kim, Ivan Anishchenko, Qian Cong, David Baker
PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS
(2019)
Article
Multidisciplinary Sciences
Jianyi Yang, Ivan Anishchenko, Hahnbeom Park, Zhenling Peng, Sergey Ovchinnikov, David Baker
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2020)
Article
Biochemical Research Methods
Julia Koehler Leman, Brian D. Weitzner, Steven M. Lewis, Jared Adolf-Bryfogle, Nawsad Alam, Rebecca F. Alford, Melanie Aprahamian, David Baker, Kyle A. Barlow, Patrick Barth, Benjamin Basanta, Brian J. Bender, Kristin Blacklock, Jaume Bonet, Scott E. Boyken, Phil Bradley, Chris Bystroff, Patrick Conway, Seth Cooper, Bruno E. Correia, Brian Coventry, Rhiju Das, Rene M. De Jong, Frank DiMaio, Lorna Dsilva, Roland Dunbrack, Alexander S. Ford, Brandon Frenz, Darwin Y. Fu, Caleb Geniesse, Lukasz Goldschmidt, Ragul Gowthaman, Jeffrey J. Gray, Dominik Gront, Sharon Guffy, Scott Horowitz, Po-Ssu Huang, Thomas Huber, Tim M. Jacobs, Jeliazko R. Jeliazkov, David K. Johnson, Kalli Kappel, John Karanicolas, Hamed Khakzad, Karen R. Khar, Sagar D. Khare, Firas Khatib, Alisa Khramushin, Indigo C. King, Robert Kleffner, Brian Koepnick, Tanja Kortemme, Georg Kuenze, Brian Kuhlman, Daisuke Kuroda, Jason W. Labonte, Jason K. Lai, Gideon Lapidoth, Andrew Leaver-Fay, Steffen Lindert, Thomas Linsky, Nir London, Joseph H. Lubin, Sergey Lyskov, Jack Maguire, Lars Malmstroem, Enrique Marcos, Orly Marcu, Nicholas A. Marze, Jens Meiler, Rocco Moretti, Vikram Khipple Mulligan, Santrupti Nerli, Christoffer Norn, Shane O'Conchuir, Noah Ollikainen, Sergey Ovchinnikov, Michael S. Pacella, Xingjie Pan, Hahnbeom Park, Ryan E. Pavlovicz, Manasi Pethe, Brian G. Pierce, Kala Bharath Pilla, Barak Raveh, P. Douglas Renfrew, Shourya S. Roy Burman, Aliza Rubenstein, Marion F. Sauer, Andreas Scheck, William Schief, Ora Schueler-Furman, Yuval Sedan, Alexander M. Sevy, Nikolaos G. Sgourakis, Lei Shi, Justin B. Siegel, Daniel-Adriano Silva, Shannon Smith, Yifan Song, Amelie Stein, Maria Szegedy, Frank D. Teets, Summer B. Thyme, Ray Yu-Ruei Wang, Andrew Watkins, Lior Zimmerman, Richard Bonneau
Article
Biochemical Research Methods
Ryan E. Pavlovicz, Hahnbeom Park, Frank DiMaio
PLOS COMPUTATIONAL BIOLOGY
(2020)
Article
Biotechnology & Applied Microbiology
Brandon Frenz, Steven M. Lewis, Indigo King, Frank DiMaio, Hahnbeom Park, Yifan Song
FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY
(2020)
Article
Multidisciplinary Sciences
Naozumi Hiranuma, Hahnbeom Park, Minkyung Baek, Ivan Anishchenko, Justas Dauparas, David Baker
Summary: DeepAccNet is a deep learning framework that estimates per-residue accuracy and residue-residue distance signed error in protein models, guiding Rosetta protein structure refinement and demonstrating improved accuracy prediction and refinement compared to other methods.
NATURE COMMUNICATIONS
(2021)
Meeting Abstract
Chemistry, Multidisciplinary
Hahnbeom Park, David Baker
ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY
(2019)