Article
Chemistry, Multidisciplinary
Peng Zhang, Qi Xu, Xiao-Mei Wang, Jia Feng, Chuan-Jun Lu, Yingzi Li, Ren-Rong Liu
Summary: The first enantioselective synthesis of N-N bisindole atropisomers via palladium-catalyzed construction of one indole skeleton is reported in this study. A wide variety of N-N axially chiral bisindoles were generated with good yields and excellent enantioselectivities through a cascade condensation/N-arylation reaction. The reaction mechanism and enantiocontrol were further investigated using density functional theory (DFT) calculations.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Hiroto Uno, Koki Kawai, Taichi Araki, Motoo Shiro, Norio Shibata
Summary: Gem-difluoromethylene moieties are attractive in medicinal chemistry due to their ability to mimic other more ubiquitous functional groups. A novel asymmetric method for their construction was developed, allowing easy access to chiral 1,3-dioxanes that contain a tetrasubstituted difluoroalkyl stereogenic center. The gem-difluoro substitution pattern promotes the reaction, and various substrates were suitable for this method.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Review
Chemistry, Multidisciplinary
Chuan-Jun Lu, Qi Xu, Jia Feng, Ren-Rong Liu
Summary: In the past few decades, the Buchwald-Hartwig reaction has played a vital role in the pharmaceuticals, materials, and catalysis fields as a powerful tool for forming C-N bonds. However, the development of asymmetric Buchwald-Hartwig amination reactions for constructing centered chirality, planar chirality, and axial chirality has been limited due to substrate scope and ligand design challenges. Recent interest in the synthesis of C-N/N-N atropisomers has led to a resurgence in asymmetric Buchwald-Hartwig amination chemistry, providing a practical protocol for the preparation of C-N atropisomers. This review discusses reported protocols and their chemical practicality.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
David Savary, Olivier Baudoin
Summary: C-H activation-based ring-forming methods are powerful for constructing complex molecular structures, especially useful for synthesizing chiral polycyclic aromatic hydrocarbons and other important organic electronic materials. A new enantioselective synthesis method using Pd-catalyzed C(sp(2))-H arylation protocol has been described, delivering diverse polycyclic compounds with high yield and good to excellent enantioselectivity, with investigation into their chiroptical properties.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Review
Chemistry, Multidisciplinary
Johannes Grosskopf, Thorsten Bach
Summary: Upon irradiation with a suitable chiral catalyst, racemic compounds can be converted into enantiopure compounds through a process called photochemical deracemization. This review comprehensively covers the research and current developments in this field, discussing the reactions and mechanistic details underlying the presented reaction. Photochemical deracemization offers a unique opportunity to directly obtain enantiopure compounds from racemates, and short-lived intermediates play a key role in determining the enantioselectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Dong-Huang Chen, Wei-Ting Sun, Cheng-Jie Zhu, Guang-Sheng Lu, Dong-Ping Wu, Ai-E Wang, Pei-Qiang Huang
Summary: The combination of transition-metal catalysis and organocatalysis has enabled chemists to achieve direct enantioselective reductive cyanation and phosphonylation of secondary amides, synthesizing enantioenriched chiral alpha-aminonitriles and alpha-aminophosphonates for the first time. The protocol is efficient, enantioselective, scalable, and the thiourea catalyst can be recycled and reused.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Guanghao Huang, Regis Guillot, Cyrille Kouklovsky, Boris Maryasin, Aurelien de la Torre
Summary: A broadly applicable diastereo- and enantioselective inverse-electron-demand Diels-Alder reaction of 2-pyrones and acyclic enol ethers is reported, leading to the synthesis of bridged bicyclic lactones with high yields and enantioselectivities using a copper(II)-BOX catalytic system. Mechanistic studies suggest a stepwise mechanism, and the synthetic potential of the bridged bicyclic lactones is demonstrated through the enantioselective synthesis of polyfunctional cyclohexenes and cyclohexadienes, as well as a carbasugar unit.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Qinglin Zhang, Kang Liang, Chang Guo
Summary: A novel electrolytic system has been introduced to divert standard ionic reactivity, providing a brand-new pattern of reactivity-electricity-driven asymmetric catalysis, which serves as a privileged chiral platform for enantioselective radical allylation.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Ken-Loon Choo, Bijan Mirabi, Karl Z. Demmans, Mark Lautens
Summary: Enantioenriched spiro-oxiranes with three contiguous stereocenters were synthesized using a rhodium-catalyzed cascade reaction, enabling the formation of a spirocyclic framework in a single step. Both sp(2)- and sp-hybridized carbon nucleophiles were found to be efficient initiators, yielding products with different functional groups. Derivatization studies demonstrated the synthetic versatility of the products' epoxide and alkyne moieties. DFT calculations were employed to explain spectroscopic discrepancies between solution- and solid-state structures of the products.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Jiaxin Han, Larry Hoteite, Joseph P. A. Harrity
Summary: The first enantioselective Pd-catalyzed asymmetric allylic alkylation of alpha-fluoro-beta-ketoesters has been achieved with up to 92% ee using Trost family chiral ligands. This work provides new insights into the modest selectivities associated with acyclic alpha-fluoroenolates and experimental evidence that poor levels of enantiocontrol in these systems are not necessarily due to E/Z enolate mixtures. Additionally, this methodology enables the easy preparation of useful 3-fluoropiperidine intermediates, demonstrating applicability to a variety of functionalization reactions for the discovery of bioactive products.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Wu-Wei Dong, Kui Tian, Xiu-Qin Dong, Chun-Jiang Wang
Summary: A series of structurally novel multifunctional chiral aminophosphine catalysts were developed through a concise synthetic strategy. These catalysts were successful in catalyzing the highly enantioselective intermolecular cross Rauhut-Currier reactions between vinyl ketones and 3-acyl acrylates and 2-ene-1,4-diones, generating a wide range of structurally important chiral multicarbonyl products with high stereocontrol.
CHINESE JOURNAL OF CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Shuai Zhang, Saima Perveen, Yizhao Ouyang, Liang Xu, Tao Yu, Min Zhao, Linghua Wang, Peidong Song, Pengfei Li
Summary: A new class of chiral bipyridine ligands, SBpy, featuring minimized steric hindrance and structural tunability, was designed and developed for the highly enantioselective Ni-catalyzed addition reaction. Compared to known methods, this reaction is more cost-effective and tolerant towards functional groups. The proposed reaction mechanism and stereocontrol model were based on experimental and computational results.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Sharad Kumbhar, Chinpiao Chen
Summary: Asymmetric allylation and vinylation of aldehydes using chromium(II)-oxazoline catalyst have been achieved, leading to high yields and enantioselectivity of homoallylic alcohols and allylic alcohols. The developed protocol offers a reliable and milder method for preparing chiral homoallylic and allylic alcohols.
CATALYSIS COMMUNICATIONS
(2021)
Article
Chemistry, Applied
Raja K. K. Rit, Hongyi Li, Stephen P. P. Argent, Katherine M. M. Wheelhouse, Simon Woodward, Hon Wai Lam
Summary: Chiral dienes are important ligands in asymmetric catalysis but they are difficult to obtain. In this study, a simple chiral allenecarboxanilide was used to produce pseudoenantiomeric bicyclo[2.2.2]octa-2,5-dienes containing an alkenyl bromide via intramolecular [4+2] cycloaddition. These compounds can be easily functionalized to provide diverse chiral diene ligands. The synthesis is straightforward and can be conducted on a large scale. The resulting ligands exhibit high performance in nine types of enantioselective Rh(I)-catalyzed addition reactions.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Applied
Byungjun Kim, Sukwoo Lee, Sarah Yunmi Lee
Summary: In this study, a new method was reported to successfully promote the catalytic asymmetric Diels-Alder reactions using a chiral catalyst in conjunction with a chiral isothiourea catalyst or a Bronsted acid, resulting in the synthesis of densely functionalized cyclohexenes with multiple stereocenters.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Review
Chemistry, Multidisciplinary
Sarina M. Berger, Todd B. Marder
Summary: Triarylboranes, known for more than 100 years, have potential applications in organic optoelectronics and have been recently explored in biological applications such as bioimaging and biomolecule sensing.
MATERIALS HORIZONS
(2022)
Article
Chemistry, Multidisciplinary
Xiaolei Zhang, Alexandra Friedrich, Todd B. Marder
Summary: A copper-catalyzed borylation reaction is reported, which involves the reaction of acyl chlorides with boron esters to produce stable potassium acyltrifluoroborates. This reaction is conducted under mild conditions and can tolerate various functional groups. It is applicable to substrates with different carbon skeletons and can be scaled up for industrial use. It is also useful for the late-stage conversion of carboxylic acid-containing drugs into acylboron analogues.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Multidisciplinary
Sinem Toksabay, Markus Leisegang, Andreas Christ, Patrick Haertl, Johannes Krebs, Todd B. Marder, Soumyajyoti Haldar, Stefan Heinze, Matthias Bode, Anke Krueger
Summary: The on-surface self-assembly of a bowl-shaped derivative on Cu(111) is reported, showing highly different arrangements at different temperatures. The formation process includes pi-stacked bowl-to-bowl dimers, chiral honeycomb structures, an intermediate trigonal superstructure, and a fully carbon-based, flattened hexagonal superstructure. This provides a potential precursor for holey graphene networks with unique defect structures.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Lukas Tendera, Felipe Fantuzzi, Todd B. Marder, Udo Radius
Summary: This study reports the synthesis of three nickel bis-boryl complexes and explores their bonding situation with the help of X-ray diffraction and DFT calculations. A delocalized, multicenter bonding scheme is observed in these complexes. The nickel complexes also show efficient catalysis in the diboration of alkynes, offering a different mechanistic pathway compared to platinum-catalyzed diboration. Stoichiometric reactions and DFT calculations are utilized to study the mechanism of the nickel-catalyzed alkyne borylation.
Article
Chemistry, Multidisciplinary
Fangyuan Zhang, Florian Rauch, Asim Swain, Todd B. Marder, Prince Ravat
Summary: This article introduces a design strategy to achieve narrow-band emission for applicable circularly polarized luminescence (CPL) active materials in ultrahigh-definition CP-OLEDs, by exploiting intramolecular donor-acceptor interactions between nitrogen and boron atoms. Single- and double-helicenes with 1,4-B,N-embedded configurationally stable structure were successfully synthesized, showing unprecedentedly narrow fluorescence and CPL bands, along with high fluorescence quantum yields.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Yuan-He Li, Su-Lei Zhang, Yong Lu, Bo Xiao, Tian-Yu Sun, Qian-Qian Xu, Jia-Hua Chen, Zhen Yang
Summary: A highly enantioselective catalytic system for exo-Diels-Alder reactions was developed using bispyrrolidine diboronates(BPDB). Activated by various Lewis or Bronsted acids, BPDB can catalyze highly stereoselective asymmetric exo-Diels-Alder reactions. The catalyst can also distinguish between different binding sites to achieve highly regioselective reactions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Hamad H. Al Mamari, Julie Borel, Aobha Hickey, Eimear Courtney, Julia Merz, Xiaolei Zhang, Alexandra Friedrich, Todd B. Marder, Gerard P. McGlacken
Summary: The quinolone-quinoline tautomerization is utilized to achieve regioselective C8-borylation of biologically important 4-quinolones. This is done by using [Ir(OMe)(cod)](2) as the catalyst precursor, the silica-supported monodentate phosphine Si-SMAP as the ligand, and B(2)pin(2) as the boron source. The resulting C8-borylated quinolines can be further converted to various derivatives with different substituents.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Physical
Arvind Barak, Nishant Dhiman, Floriane Sturm, Florian Rauch, Yapamanu Adithya Lakshmanna, Karen S. Findlay, Andrew Beeby, Todd B. Marder, Siva Umapathy
Summary: The compound DACM-DPA exhibits significant charge transfer character in the excited state in polar solvents. Transient absorption measurements show different excited-state lifetimes in n-hexane, acetonitrile, and methanol. Raman measurements reveal the structural dynamics and the formation of an intramolecular charge-separated state.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Biochemistry & Molecular Biology
Lidija-Marija Tumir, Dijana Pavlovic Saftic, Ivo Crnolatac, Zeljka Ban, Matea Maslac, Stefanie Griesbeck, Todd B. Marder, Ivo Piantanida
Summary: A series of tetracationic bis-triarylborane dyes with different aromatic linkers showed high affinities towards ds-DNA and ds-RNA. The linker influenced the emissive properties of triarylborane cations and controlled the fluorimetric response of dyes. The different dye analogs exhibited selective or non-selective fluorescence responses and induced circular dichroism signals depending on the DNA/RNA sequences.
Article
Chemistry, Organic
Shu-Min Lu, Chao Chen, Chang Liu, Rudong Liu, Jia-Hua Chen, Zhongchao Zhang, Zhen Yang
Summary: Regioselective synthesis of 5,6,7-trihydroxyl and 5,7,8-trihydroxyl flavones was achieved using a transition-metal-catalyzed C-H oxidation with naturally enriched 5,7-dihydroxyl flavone as the starting material. This method was applied to the synthesis of biologically active flavonoids wogonin, oroxylin A, and their glycosylated derivatives as potential carnitine palmitoyltransferase 1 activators.
Article
Chemistry, Multidisciplinary
Lukas Tendera, Laura Kuehn, Todd B. Marder, Udo Radius
Summary: The synthesis of the first terminal mono-boryl complexes of nickel, without a pincer ligand, is reported. Various reactions were conducted to exchange ligands and obtain the desired nickel mono-boryl complexes.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Hao-Yuan Liu, Zhen-Yu Zhang, Yi-Ke Zhou, Jia-Hua Chen, Zhen Yang, Yuan-He Li
Summary: This paper presents an efficient strategy for synthesizing the DEFGH rings of phainanoid F, involving a photo-induced electrocyclization and a homoallylic elimination. It is noteworthy that the electrocyclization reaction was used to simultaneously construct two vicinal quaternary carbons in total synthesis, which is a rare example. The strategy outlined here serves as the basis for the total synthesis of Phainanoid F and could be applied in synthesizing other natural products with similar 13,30-cyclodammarane skeletons.
CHEMISTRY-AN ASIAN JOURNAL
(2023)
Article
Chemistry, Organic
Zhenyu Zhang, Wei Zhang, Jun-Chen Tang, Jin-Teng Che, Zhongchao Zhang, Jia-Hua Chen, Zhen Yang
Summary: The researchers synthesized (+)-Haperforin G in 20 steps from commercially available starting materials. They used a Co-catalyzed intramolecular Pauson-Khand reaction to selectively construct a cyclopentanone with an all-carbon quaternary stereogenic center at the bridge-head position. Light-initiated photocatalysis was employed for the convergent and asymmetric cross-coupling of the unstabilized C(sp(3)) radical with an enone. This developed chemistry opens up possibilities for synthesizing structurally diverse analogs of haperforin G (6).
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Medicinal
Marta Jurkovic, Matthias Ferger, Isabela Draskovic, Todd B. Marder, Ivo Piantanida
Summary: This study presents a novel triarylborane (TB)-dye that serves as both an NMe2 pi-donor and an inductive NMe2-alkyl cationic acceptor. The TB-dye is highly sensitive to a click reaction with an azide-substituted lysine side chain, resulting in a significant red shift of emission. Furthermore, the TB-dye exhibits high affinities towards both DNA and proteins, making it an ideal fluorimetric probe for detecting the progress of click reactions and sensing the binding site composition.
Article
Chemistry, Multidisciplinary
Jiefeng Hu, Man Tang, Jing Wang, Zhu Wu, Alexandra Friedrich, Todd B. Marder
Summary: We report the design and synthesis of a stable, multifunctional (diborylmethyl)iodide reagent for the photoinduced cyclopropanation of alkenes, providing an array of 1,2-substituted cyclopropylboronates in good yields. The protocol displays high chemo- and diastereoselectivity, excellent functional-group tolerance, and allows for late-stage borylcyclopropanation of complex molecules. Mechanistic studies reveal that the borylcyclopropanation proceeds through a radical addition/polar cyclization pathway mediated by the photocatalyst fac-Ir(ppy)(3) and visible light.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
