Article
Chemistry, Multidisciplinary
Francis Bru, Mathieu Lesieur, Albert Poater, Alexandra M. Z. Slawin, Luigi Cavallo, Catherine S. J. Cazin
Summary: The synthesis and isolation of [Pd(NHC)(PhC equivalent to CPh)] complexes were reported, which are new 14-electron Pd(0)-complexes that serve as key synthons for known palladium(0) and palladium(II) species and allow access to unprecedented mixed NHC-phosphite palladium(0) complexes. These complexes are also capable of catalyzing the facile hydrosilylation of allenes. DFT calculations provided insights into the relatively weak interaction between the metal and the diphenylacetylene ligand, comparing it with other ligands with varying coordinating power, structure, and electronic properties.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Applied
Orhan Altan
Summary: This study investigates the catalytic activity of Pd (II) complexes of phosphino-benzaldoxime ligands in Suzuki-Miyaura coupling reactions. The results show that reducing the amount of catalyst leads to an increase in catalytic activity, and it is found that palladium nanoparticles formed in the reaction medium are responsible for this activity. This study contributes to the debate over whether the catalytic activity of phosphine-palladium complexes in SMC reactions results from a homogeneous or heterogeneous pathway.
APPLIED ORGANOMETALLIC CHEMISTRY
(2022)
Article
Chemistry, Applied
Seoyoung Lee, Juyeong Kim, Kyungjun Kang, Ansoo Lee, Hyunwoo Kim
Summary: In this study, we developed a ligand-controlled palladium-catalyzed allylic substitution approach that selectively achieves [1+1] and [1+2] allylic aminations between allylic diols and diamines. By combining this approach with sequential acetylation and allylic amination, tetraazamacrocycles with ring sizes ranging from 16 to 38 were successfully synthesized. These findings demonstrate the potential of a sequential allylation strategy for synthesizing complex molecules with broad applications in the fields of chemistry, pharmaceuticals, and medicine.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Nardana Sivendran, Nico Pirkl, Zhiyong Hu, Angelino Doppiu, Lukas J. Goossen
Summary: Halogen-bridged methylnaphthyl (MeNAP) palladium dimers, presented as versatile Pd precursors, demonstrate excellent catalytic performance by in situ conversion into well-defined monoligated complexes. They show benchmark activities in challenging reactions, enable record-setting yields, and can achieve previously elusive cross-couplings.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Biochemistry & Molecular Biology
Kalok Chan, Long Thanh Ta, Yong Huang, Haibin Su, Zhenyang Lin
Summary: In this study, a simple molecular representation method was developed using machine learning and artificial intelligence techniques to predict rate constants of aryl bromides in palladium-catalyzed Sonogashira coupling reactions. The results demonstrate the importance of incorporating domain knowledge into machine learning for improved data analysis.
Article
Chemistry, Inorganic & Nuclear
Jie Dong, Dandan Yang, Baiquan Wang
Summary: A series of allyl palladium and nickel complexes based on imidazo[1,5-a]pyridine sulfonate ligands were synthesized and characterized. The palladium complexes showed high activity in norbornene polymerization and copolymerization with BVE, while the nickel complexes exhibited similar activity and were more suitable for copolymerization with BVE and ABE. The steric hindrance of the substituent affected the catalytic activity of the complexes in both systems.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
James E. Baumann, Gojko Lalic
Summary: A new method for the differential dihydrofunctionalization of terminal alkynes has been developed, enabling the synthesis of allylic boronate esters through a reductive three-component coupling reaction. This transformation, promoted by a copper/palladium catalyst system, hydrofunctionalizes both pi-bonds of the alkyne. The method is compatible with a wide range of functional groups.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Applied
Takahiro Yamada, Kosaku Tanaka, Yoshimitsu Hashimoto, Nobuyoshi Morita, Osamu Tamura
Summary: Here, the authors describe a reaction system based on Pd(II) catalyst and Tl(OCOCF3)3 for the electrophilic C3-H alkenylation of 2,6-dialkoxypyridines with alkenes. The synergistic action of the Pd/thioether ligand catalytic system and Tl(III) enables efficient C-H alkenylation of various nitrogen heteroaromatics with complete regioselectivity. Mechanistic studies suggest that the reaction proceeds via electrophilic thallation of heteroarenes followed by Pd-catalyzed Heck-type reaction.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Physical
Simon Sieger, Ilja Lubins, Bernhard Breit
Summary: A highly versatile palladium-catalyzed allylation reaction has been reported, providing a waste-free access to allylated nucleophiles with unlimited possibilities for further functionalization. The reaction can be conducted using propadiene in toluene, and the mechanism is supported by deuterium labeling experiments.
Article
Chemistry, Physical
Simon V. Sieger, Ilja Lubins, Bernhard Breit
Summary: A highly versatile palladium-catalyzed allylation reaction using various pronucleophiles has been reported. Through the use of propadiene in toluene, this reaction provides an efficient and waste-free method to obtain allylated nucleophiles with unlimited potential for further functionalization. The Pd/BINAP system is not only capable of adding N-, O-, and S-pronucleophiles, but also C-pronucleophiles to allene. The plausible mechanism is supported by deuterium labeling experiments.
Article
Chemistry, Physical
Diego Olivieri, Riccardo Tarroni, Stefano Zacchini, Nicola Della Ca', Raffaella Mancuso, Bartolo Gabriele, Gilberto Spadoni, Carla Carfagna
Summary: The direct alkoxy-aryloxycarbonylation reaction of olefins has been achieved for the first time, leading to the formation of mixed alkyl aryl succinates. The reaction shows high regioselectivity and moderate to excellent yields. Detailed DFT calculations and experimental results support the proposed catalytic cycle, which involves the crucial role of p-benzoquinone as both regenerating the active species and promoting the final elimination step.
JOURNAL OF CATALYSIS
(2023)
Review
Chemistry, Multidisciplinary
Xinpeng Cheng, Liming Zhang
Summary: This review highlights the progress made in developing remotely functionalized biaryl-2-ylphosphine ligands and using them in cooperative gold catalysis to achieve excellent catalytic efficiency or realize previously unknown reactivities. This approach also opens up new possibilities for implementing asymmetric gold catalysis.
Review
Chemistry, Multidisciplinary
Justus Diekamp, Thomas Seidensticker
Summary: The recycling of homogeneous catalysts in a homogeneous matrix is a challenging task for many reactions aiming for industrial applications. Although various synthetic approaches for recyclable homogeneous catalysts exist, a concise overview of catalyst modifications is lacking in the literature. This review aims to fill this gap by summarizing the existing synthesis pathways for polar, non-polar, fluorous, and molecular-weight-enlarged catalysts and examining their modular and late-stage approaches. Additionally, the potential for a generally applicable tag library to facilitate catalyst modifications for specific recycling strategies is explored.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Man Ho Tse, Rong-Lin Zhong, Fuk Yee Kwong
Summary: In this study, a general Pd-catalyzed Miyaura borylation of sterically hindered aryl chlorides was achieved using a tailor-made phosphine ligand. The success of this reaction demonstrated the possibility of coupling highly sterically congested electrophilic partners and showed good functional group compatibility. The ligand-enabled C-B bond formation could provide fundamental knowledge for developing catalyst systems suitable for other highly sterically hindered cross-coupling reactions.
Article
Chemistry, Multidisciplinary
Sylvain Sudan, Ru-Jin Li, Suzanne M. Jansze, Andre Platzek, Robin Rudolf, Guido H. Clever, Farzaneh Fadaei-Tirani, Rosario Scopelliti, Kay Severin
Summary: The design of structurally defined heteroleptic coordination cages is challenging and only a few examples are known. In this study, a novel hexanuclear Pd cage containing two types of dipyridyl ligands was identified using a selection approach. The structure of the cage was elucidated by single-crystal X-ray diffraction, revealing an unprecedented trigonal-antiprismatic cage structure.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Chemistry, Organic
Jindian Duan, Pui Ying Choy, Kin Boon Gan, Fuk Yee Kwong
Summary: A general protocol for N-difluoromethylation of aniline derivatives using commercially available ethyl bromodifluoroacetate as a difluorocarbene source is developed, which exhibits notable operational simplicity, wide functional group tolerance, and good-to-excellent product yields.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Review
Chemistry, Organic
Yi Ling Tsang, Pui Ying Choy, Man Pan Leung, Xinwei He, Fuk Yee Kwong
Summary: Rhodium-catalysed cross-dehydrogenative coupling (CDC) has attracted considerable attention as an attractive synthetic tool for selective C-C bond formation. This process eliminates the need for pre-functionalised starting materials and generates minimal metallic waste, making it more environmentally friendly and sustainable. Moreover, it offers a straightforward synthetic approach using simple materials, resulting in better step- and atom economy.
ORGANIC CHEMISTRY FRONTIERS
(2022)
Article
Chemistry, Physical
Man Ho Tse, Rong-Lin Zhong, Fuk Yee Kwong
Summary: In this study, a general Pd-catalyzed Miyaura borylation of sterically hindered aryl chlorides was achieved using a tailor-made phosphine ligand. The success of this reaction demonstrated the possibility of coupling highly sterically congested electrophilic partners and showed good functional group compatibility. The ligand-enabled C-B bond formation could provide fundamental knowledge for developing catalyst systems suitable for other highly sterically hindered cross-coupling reactions.
Article
Chemistry, Multidisciplinary
Kin Boon Gan, Rong-Lin Zhong, Zhen-Wei Zhang, Fuk Yee Kwong
Summary: In this study, a rational design of a new collection of chiral phosphines featuring a C-N axial chirality is presented. These phosphines were successfully applied in the enantioselective synthesis of highly steric hindered tetra-ortho-substituted biaryls. It was found that the carbazolyl framework played a crucial role in facilitating the reaction through a fleeting Pd-N/Pd-pi coordination.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Review
Chemistry, Multidisciplinary
Man Ho Tse, Pui Ying Choy, Fuk Yee Kwong
Summary: This article presents a promising collection of phosphine ligands and explores their applications in modern arylation processes. Using a readily accessible 2-arylindole scaffold, three major phosphino-moiety-positioned ligand series can be generated. The study shows that the balance of steric and electronic properties of phosphine ligands is crucial for the success of the reaction.
ACCOUNTS OF CHEMICAL RESEARCH
(2022)
Review
Chemistry, Multidisciplinary
Pui Ying Choy, Kin Boon Gan, Fuk Yee Kwong
Summary: Sonogashira cross-coupling protocol allows the construction of C(sp(2))-C(sp) bond through the reaction between aryl/vinyl halide and terminal alkyne. The resulting internal alkynes are versatile for the synthesis of various functionalized alkyne-containing scaffolds or as valuable synthetic synthons. The reaction conditions can be adjusted to activate hindered and/or electron-rich electrophiles, and Pd-catalyzed copper-free Sonogashira coupling reaction has gained attention for being more environmentally friendly and allowing convergent synthesis in a one-pot manner.
CHINESE JOURNAL OF CHEMISTRY
(2023)
Review
Chemistry, Multidisciplinary
Pui Ying Choy, Man Ho Tse, Fuk Yee Kwong
Summary: Transition metal-catalyzed borylation is a powerful strategy for synthesizing organoboron compounds, and it finds widespread applications in various fields. This review provides a concise summary of recent advances in palladium- and rhodium-catalyzed borylation, highlighting catalyst systems, substrates scope, and reaction conditions. The discussion also includes the diverse array of borylative products obtained and future directions for more efficient and selective methodologies.
CHEMISTRY-AN ASIAN JOURNAL
(2023)
Article
Chemistry, Organic
Yanan Liu, Pui Ying Choy, Demao Wang, Mengdi Wu, Qiang Tang, Xinwei He, Yongjia Shang, Fuk Yee Kwong
Summary: A 1,8-diazabicyclo[5.4.0]-undec-7-ene-promoted cascade double-annulation of ortho-alkynyl quinone methide is developed for constructing of 2-aryl-4-hydroxybenzo-[c]-chromen-6-ones. This method offers operational simplicity and good functional group compatibility.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Xinwei He, Ruxue Li, Pui Ying Choy, Jiahui Duan, Zhenzhen Yin, Keke Xu, Qiang Tang, Rong-Lin Zhong, Yongjia Shang, Fuk Yee Kwong
Summary: An operationally simple and environmentally friendly method for the modular and regioselective synthesis of (E)-4-(vinyl or aryl or alkynyl)iminochromenes from propargylamines and S-methylated beta-ketothioamides using FeCl3 in undried acetonitrile and air atmosphere is reported. This method exhibits a broad substrate scope and nice functional group compatibility, providing an efficient access to 3,4-disubstituted iminochromenes.
