Article
Chemistry, Organic
Muniyappa Vijaykumar, Chandini Pradhan, Rajesh G. Gonnade, Benudhar Punji
Summary: The palladium-catalyzed chemoselective oxygenation of C(sp2)-H and C(sp3)-H bonds in substituted isatin derivatives is described. This mild protocol allows for the C5 C(sp2)-H oxygenation of isatins through electrophilic intermolecular C-H palladation in concentrated solutions using PhI(OAc)2 or Selectfluor as an oxidant, while the N-CH3 C(sp3)-H oxygenation is achieved in dilute solutions via carbonyl-assisted intramolecular palladation in the presence of K2S2O8. This oxygenation reaction provides a direct and unified approach for synthesizing diverse oxygenated isatins with sensitive functionalities, including biorelevant compounds.
Article
Chemistry, Multidisciplinary
Anton Kudashev, Olivier Baudoin
Summary: A ligand-controlled site-selective C(sp(3))-H arylation of heteroaromatic ketones has been developed using Pd catalysis, with selective reactions occurring at the alpha- or beta-position of the ketone side-chain. Addition of a pyridone ligand enables switching from alpha- to beta-arylation. The alpha-arylation process demonstrates broad scope and high site- and chemoselectivity, while the beta-arylation is more limited, with mechanistic investigations suggesting different pathways for the two processes.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Physical
Garrett P. R. Freure, Eric A. Skrotzki, Jean-Danick E. Lavertu, Stephen G. Newman
Summary: Various methods have been investigated recently for the arylation of weakly acidic C(sp(3))-H bonds, with this study focusing on a base-mediated approach using organometallic superbases. The study developed conditions for high selectivity metalation using either n-BuLi/diamine or n-BuLi/KOtBu superbases, allowing for direct use in cross-coupling or formation of organozincs for reactions with functional groupdense organohalides.
Article
Chemistry, Physical
Tyler G. Saint-Denis, Nelson Y. S. Lam, Nikita Chekshin, Paul F. Richardson, Jason S. Chen, Jeff Elleraas, Kevin D. Hesp, Daniel C. Schmitt, Yajing Lian, Chan Woo Huh, Jin-Quan Yu
Summary: Enantioselective C(sp(3))-H activation has attracted significant interest, but the mechanisms responsible for enantioselection remain unclear. This study found extreme sensitivity differences in two substrate classes, leading to high enantiomeric ratios for thioether-directed-C(sp(3))-H arylation. The exploitation of transient chirality at sulfur was key to achieving stereochemical information transfer from ligand backbone to substrate carbons.
Article
Chemistry, Physical
Yuan Xue, Han Seul Park, Chao Jiang, Jin-Quan Yu
Summary: In this study, a Pd(II)-catalyzed beta-C(sp(3))-H nitrooxylation of ketones and native amides was reported. The use of fine-tuned removable aminooxyamide auxiliary enabled beta-C(sp(3))-H functionalization of various aliphatic ketones. Palladacycle intermediates were isolated to elucidate the reaction mechanism for ketones C(sp(3))-H activation with the L,X-type imino-amide directing group.
Article
Chemistry, Physical
Zengbing Bai, Qingqing Chen, Jun Gu, Chuangxu Cai, Jie Zheng, Wangjian Sheng, Shandong Yi, Fang Liu, Huan Wang
Summary: The paper introduces a versatile strategy based on late-stage palladium-catalyzed C-H activation for synthesizing peptides with backbone thiazole motifs, enabling site-selective arylation in peptide side chains and expanding the structural diversity of peptide compounds. This method exhibits high biocompatibility and is capable of efficiently constructing peptide libraries with featured backbone thiazole units.
Article
Chemistry, Multidisciplinary
Quan-Zhe Li, Si-Hua Hou, Jun-Chen Kang, Peng-Fei Lian, Yu Hao, Chao Chen, Jia Zhou, Tong-Mei Ding, Shu-Yu Zhang
Summary: Bioinspired palladium-catalyzed intramolecular cyclization of amino acid derivatives containing a vinyl iodide moiety by C-H activation enabled rapid access to a wide range of functionalized proline derivatives with an exocyclic olefin. The functionalized prolines were used as intermediates for the synthesis of several natural products: lucentamycin A, oxotomaymycin, oxoprothracarcin, and barmumycin.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Mario Martinez-Mingo, Ines Alonso, Nuria Rodriguez, Ramon Gomez Arrayas, Juan C. Carretero
Summary: Mechanistic insights into chemoselectivity control in Pd-catalyzed reactions have enabled the access to different heterocyclic frameworks from the same starting substrate by manipulating the reaction conditions.
CATALYSIS SCIENCE & TECHNOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Mario Martinez-Mingo, Andres Garcia-Viada, Daniel Sowa Prendes, Ines Alonso, Nuria Rodriguez, Ramon Gomez Arrayas, Juan C. Carretero
Summary: The selective delta-C(sp(3))-H acetoxylation of N-(SO2Py)-protected amino acid derivatives has been achieved using palladium-catalysis and PhI(OAc)(2) as both oxidant and acetoxy source. The unique structural and electronic features of SO2Py are crucial in overriding the more favorable intramolecular C-H amination.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Yi-Hao Li, Yuxin Ouyang, Nikita Chekshin, Jin-Quan Yu
Summary: Pd(II)-catalyzed gamma-C(sp3)-H (hetero)arylation of aliphatic ketones using alpha-amino acids as transient directing groups (TDG) has been developed. By reducing the loading of acid additives, the crucial ligand effect of 2-pyridone is enhanced, leading to improved reactivity and the possibility of cyclic gamma-methylene C(sp3)-H arylation of ketones. Mechanistic investigation and comparison to the gamma-C-H arylation of aldehydes provide structural insights for designing site-selective TDGs.
Article
Chemistry, Organic
Hyeonbin Ha, Ho Jeong Choi, Hahyoun Park, Yunyeong Gwon, Jiin Lee, Jaesung Kwak, Min Kim, Byunghyuck Jung
Summary: The research reveals the use of 3-bromo-2-hydroxybenzaldehyde as a transient directing group in the Pd-catalyzed gamma-position sp(3)-C-H arylation of primary amines, and detailed the reaction mechanism and high selectivity origins through density functional theory calculations and X-ray crystal structure analysis.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Jinquan Zhang, Shuaizhong Zhang, Hongbin Zou
Summary: The study introduces a new Pd-catalyzed gamma-C(sp(3))-H selective alkylation and alkenylation reaction with removable 7-azaindole as a directing group. Acid and base were found to be decisive regulators for selective alkylation and alkenylation on the same substrate under the same reaction conditions. The results demonstrate the potential of the strategy for structurally diverse aliphatic chain extension and functionalization.
Article
Chemistry, Organic
Liming Yang, Henan Xie, Guanghui An, Guangming Li
Summary: In this study, a new method was developed to enhance the coordination of Pd catalysts with weak-coordinating substrates using a commercially available sulfonic acid, enabling arylation and alkenylation of C(sp(3))-H bonds of Weinreb amides.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Chen-Hui Yuan, Xiao-Xia Wang, Lei Jiao
Summary: We developed sulfoxide-2-hydroxypridine (SOHP) ligands that showed great efficiency in the Pd-catalyzed C(sp(2))-H activation. In this study, we presented an efficient asymmetric Pd-II/SOHP-catalyzed beta-C(sp(3))-H arylation of aliphatic tertiary amides, where the SOHP ligand played a crucial role in the stereoselective C-H deprotonation-metalation step.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Huaquan Fang, Kaixue Xie, Sebastian Kemper, Martin Oestreich
Summary: The study demonstrates that Tris(pentafluorophenyl)borane catalyzes the two-fold C(sp(3))-H silylation of various trialkylamine derivatives with dihydrosilanes, resulting in the formation of 4-silapiperidines in decent yields. The reaction cascade involves amine-to-enamine dehydrogenation at two alkyl residues and two electrophilic silylation reactions of those enamines, one inter- and one intramolecular.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Qi Zhang, Haizhu Yu, Yao Fu
SCIENCE CHINA-CHEMISTRY
(2015)
Article
Chemistry, Organic
Qi Zhang, Ming-Chen Fu, Hai-Zhu Yu, Yao Fu
JOURNAL OF ORGANIC CHEMISTRY
(2016)
Article
Chemistry, Inorganic & Nuclear
Qi Zhang, Hai-Zhu Yu, Yao Fu
Article
Chemistry, Physical
Qi Zhang, Zhen-Qi Zhang, Yao Fu, Hai-Zhu Yu
Article
Chemistry, Organic
Qi Zhang, Bing Wang, Jia-Qin Liu, Yao Fu, Yu-Cheng Wu
JOURNAL OF ORGANIC CHEMISTRY
(2018)
Article
Chemistry, Inorganic & Nuclear
Qi Zhang, Mo Li, Jia-Qin Liu, Hai-Zhu Yu
JOURNAL OF ORGANOMETALLIC CHEMISTRY
(2018)
Article
Chemistry, Inorganic & Nuclear
Qi Zhang, Hai-Zhu Yu, Yi-Tong Li, Lei Liu, Yong Huang, Yao Fu
DALTON TRANSACTIONS
(2013)
Article
Chemistry, Organic
Qi Zhang, Hai-Zhu Yu, Yao Fu
Organic Chemistry Frontiers
(2014)
Article
Chemistry, Physical
Qi Zhang, Xiaofei Zhang, Mo Li, Jiaqin Liu, Yucheng Wu
APPLIED SURFACE SCIENCE
(2019)
Article
Chemistry, Physical
Jiaqin Liu, Mo Li, Xiaofei Zhang, Qi Zhang, Jian Yan, Yucheng Wu
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2019)
Article
Chemistry, Physical
Zhang Qi, Yu Hai-Zhu, Shi Jing
ACTA PHYSICO-CHIMICA SINICA
(2013)