Article
Chemistry, Organic
Gangarajulu Kesavulu, Biguvu Balachandra, Kavirayani R. Prasad
Summary: The use of lithio tris(methylthio)methane as an anion equivalent enables the synthesis of α-amino acids. Reactions with nonracemic sulfinimines yield α-sulfinamido trithioformates with excellent diastereoselectivity. Conversion of trithioformates to diverse functionalities such as α-amino acid thioesters, esters, anilides, amides, and di/tripeptides is achieved without epimerization of chiral centers.
Article
Chemistry, Multidisciplinary
Rosa Lopez, Claudio Palomo
Summary: N,N-Diacylaminals are flexible molecular scaffolds commonly used as amide surrogates in peptidomimetics. Recently, their singularity as an N-acyl imine equivalent and hydrogen-bond donor has led to new synthetic opportunities, particularly in the field of asymmetric catalysis. This concept article highlights the diverse synthetic potential of N,N-Diacylaminals and provides the necessary elements for further developments.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Review
Chemistry, Applied
Gabriele Lupidi, Alessandro Palmieri, Marino Petrini
Summary: N-Activated ketimines are characterized by electron-withdrawing groups linked to the nitrogen atom, enhancing the electrophilic character and allowing addition reactions with weak nucleophiles. The presence of oxygen atoms in these groups is crucial for asymmetric catalytic reactions. This review summarizes the literature on the synthesis of optically active alpha-substituted amino derivatives using open-chain N-activated ketimines.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Organic
Erick Martinez-Toto, Mario Ordonez, Juan C. Morales-Solis, Marcos Flores-Alamo
Summary: The diastereoselective synthesis of (2S,5R)-5-methyl-5-(phosphono)-proline, a phosphoproline derivative from L-pyroglutamic acid, is reported. The key feature of this method is the use of chiral cyclic imines as intermediates and the selective nucleophilic addition of phosphites. The target compound is obtained through cleavage and hydrolysis reactions.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Review
Chemistry, Applied
Hao-Qiang Cao, Jun-Kuan Li, Fa-Guang Zhang, Dominique Cahard, Jun-An Ma
Summary: This review comprehensively summarizes modern synthetic methods towards asymmetric construction of chiral amino carboxylic-phosphonic acid derivatives, including phosphono-containing amino acid derivatives and catalytic enantioselective synthesis as a potent strategy. Topics such as chiral resolution protocols, chiral auxiliary-directed syntheses, and valorization of abundant chiral amino acid resources are also discussed.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Review
Chemistry, Multidisciplinary
Fujie Tanaka
Summary: This article discusses catalysts and catalyst systems that use amino acids, primary, secondary, and/or tertiary amines as key catalytic functional groups to accelerate chemical transformations. It also explores strategies and methods that utilize amine derivatives as catalysts. The understanding of dynamics and kinetic controls in amine-catalyzed reactions has enabled the synthesis of complex molecules in stereocontrolled manners.
Article
Chemistry, Applied
Izabela Weglarz, Karol Michalak, Jacek Mlynarski
Summary: The study reported the first successful enantioselective hydrosilylation of cyclic imines promoted by a chiral zinc complex, achieving pharmaceutically relevant enantioenriched 2-aryl-substituted pyrrolidines with excellent enantioselectivities. The synthetic utility of the presented methodology was demonstrated in an efficient synthesis of pharmaceutical drug precursors to Aticaprant and Larotrectinib.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Multidisciplinary
Jia-Bin Pan, Zhi-Chun Yang, Xuan-Ge Zhang, Mao-Lin Li, Qi-Lin Zhou
Summary: Here, we present a method for enantioselective phosphoric acid catalyzed amination of ketenes generated from α-aryl-α-diazoketones. Mechanistic studies elucidated the reaction pathway and explained how the catalyst expedited the transformation and controlled the enantioselectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Feng Jiang, Tengfei Meng, Ying Zhou, Zhenying Xiong, Yupei Zhao, Wengang Guo
Summary: We report an enantio- and diastereodivergent synthesis of enantioenriched fluorenes with broad substrate scope and high enantioselectivity (up to 99% ee) under low catalyst loading (0.1 mol %). The success of this method lies in the pseudo-diastereodivergent desymmetrization of stereoisomers of meso-epoxides enabled by the same organocatalyst. Furthermore, some of the chiral fluorenes obtained exhibit high fluorescence quantum yields (up to 76.6%), as evidenced by photophysical properties studies.
Article
Chemistry, Multidisciplinary
Ke-Wei Chen, Zhi-Han Chen, Shuang Yang, Shu-Fang Wu, Yu-Chen Zhang, Feng Shi
Summary: A new strategy has been developed for the highly atroposelective synthesis of N-N axially chiral indole scaffolds and bispyrroles, which can be used as chiral organocatalysts and exhibit potent anticancer activity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Organic
Xiaoxue Tang, Zhishan Su, Liqiao Yan, Qiong Tang, Shunxi Dong, Lili Lin, Xiaoming Feng
Summary: Highly diastereo- and enantioselective allylation of isatins with 3-substituted allylboronic compounds was achieved using the chiral N,N'-dioxide/Lu(OTf)(3) complex, leading to enantioenriched 3-allyl-3-hydroxyoxindoles with adjacent tetrasubstituted tertiary or tetrasubstituted quaternary stereogenic centers. The synthetic utility of the reaction was demonstrated by further transformation of the product to a tetrahydrofuranyl oxindole derivative.
Article
Chemistry, Physical
Kuldeep Singh, Idan Avigdori, Alexander Kaushansky, Natalia Fridman, Dor Toledano, Mark Gandelman
Summary: Nitrogen Lewis acids (NLAs) have emerged as a powerful tool in strong bond activation and catalysis. This article presents the synthesis and characterization of a new generation of nitrenium-based Lewis acids and demonstrates their efficiency in gram-scale hydrosilylation reactions. Experimental and theoretical studies provide insights into the mechanistic action of nitrenium Lewis acids in reduction-type reactions.
Article
Chemistry, Multidisciplinary
Donggeon Nam, Antonio Tinoco, Zhuofan Shen, Ronald D. Adukure, Gopeekrishnan Sreenilayam, Sagar D. Khare, Rudi Fasan
Summary: This study presents a biocatalytic strategy utilizing engineered variants of cytochrome c(552) to synthesize enantioenriched alpha-trifluoromethyl amines with high yield and enantioselectivity. The methodology can be applied to a broad range of substrates, providing a chemoenzymatic access to valuable compounds for medicinal chemistry and the synthesis of bioactive molecules.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Organic
Chuan-Wei Feng, Dan-Yan Wang, Hui-Ling Lu, Zi-Wei Xi, Yong-Miao Shen, Jianyu Cao
Summary: We have developed an efficient visible light-driven method for synthesizing sulfinamides and sulfoxides, which is versatile and easily scalable.
Article
Chemistry, Organic
Apoorva Malik, Pragati R. Sharma, Rakesh K. Sharma
Summary: We report a class of quaternary ammonium Cinchona-functionalized crown ether-strapped calix[4]-arene phase-transfer catalysts for the efficient enantioselective alpha-alkylation of glycine imines. The catalyst exhibits excellent catalytic performance at 0.1 mol % catalytic loading, affording the desired alpha-alkylated glycinates with 98% yield and 99.9% ee. The catalyst could be recovered and recycled up to 30 test cycles without a significant drop in activity.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Applied
Vladimir Yu. Vaganov, Yasuaki Fukazawa, Nikolay S. Kondratyev, Sergei A. Shipilovskikh, Steven E. Wheeler, Aleksandr E. Rubtsov, Andrei V. Malkov
ADVANCED SYNTHESIS & CATALYSIS
(2020)
Article
Chemistry, Organic
Aleksandr E. Rubtsov, Andrei V. Malkov
Summary: Asymmetric crotylation has become an important tool in organic synthesis for stereoselective construction of carbon skeletons. The use of organometallic reagents based on silicon and boron, as well as the development of new chiral Lewis base catalysts, are highlighted in this account. Additionally, a novel protocol for kinetic resolution of racemic secondary allylboronates has been discussed in the context of setting up stereogenic centers.
Article
Chemistry, Organic
Simona Zeimyte, Sigitas Stoncius
Summary: The newly synthesized chiral Lewis basic bipyridine N,N'-dioxides exhibited good catalytic activity in asymmetric synthesis reactions, providing high yields of target products, but the enantioselectivity needs improvement.
Article
Energy & Fuels
Sona Ulicna, Liam M. Welch, Ali Abbas, Mustafa Togay, Vincent Tsai, Tom R. Betts, Andrei Malkov, John M. Walls, Jake W. Bowers
Summary: This study discusses a novel strategy for Na-doping in CIGS absorbers through thermal evaporation of NaCl, leading to enhanced grain growth and improved efficiency of solution-processed solar cells. The effect of Na on device performance is mainly attributed to morphological changes and carrier collection improvements, showcasing the potential of Na as a dopant in CIGS absorbers.
PROGRESS IN PHOTOVOLTAICS
(2021)
Review
Chemistry, Organic
Aleksandr E. Rubtsov, Andrei V. Malkov
Summary: This review discusses recent advances in the synthesis of 2,2'-bipyridines, focusing on both the synthesis of compounds with specific substitution patterns and the development of new methods for assembling the bipyridine core. Special attention is given to the use of pyridine N-oxides and metal-free protocols to facilitate the formation of bipyridines in this field of research.
SYNTHESIS-STUTTGART
(2021)
Article
Chemistry, Analytical
Jan Klouda, Lenka Benesova, Pavel Kocovsky, Karolina Schwarzova-Peckova
Summary: 7-Dehydrocholesterol is an essential biomarker for Smith-Lemli-Opitz syndrome, and its electrochemical oxidation allows for voltammetric determination, providing clinical value for diagnosis and monitoring. This study establishes a reliable method for diagnosing SLOS and monitoring the biotransformation of 7-dehydrocholesterol to cholecalciferol.
Article
Chemistry, Multidisciplinary
Ahmed M. Sheta, Anas Alkayal, Mohammad A. Mashaly, Samy B. Said, Saad S. Elmorsy, Andrei V. Malkov, Benjamin R. Buckley
Summary: In this study, an electrochemical approach was explored for the hydrocarboxylation of α,β-unsaturated alkenes with excellent regioselectivity and the ability to carboxylate hindered substrates to afford α-quaternary center carboxylic acids. The process reported requires no chromatography, and products can be purified by simple crystallization from the reaction mixture after work-up.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Vidmantas Bieliunas, Sigitas Stoncius
Summary: The design and synthesis of second generation C-2-symmetric ligands with additional substituents was reported. These substituents provide a further element for fine-tuning the ligand structure by enforcing conformational rigidity. The tetrasubstituted bicyclo[3.3.1]nona-2,6-dienes were successfully employed in the rhodium-catalyzed arylation reaction with good to excellent yields and enantioselectivities up to 99% ee.
Article
Chemistry, Organic
Petr Matous, Michal Majek, Ondrej Kysilka, Jiri Kunes, Jana Marikova, Ales Ruzicka, Milan Pour, Pavel Kocovsky
Summary: The method of workup has a significant impact on the annulation of benzonitriles ArC equivalent to N, resulting in different products depending on whether the reaction is quenched slowly with water or poured slowly into water. This study provides insights into the mechanism of the processes and the role of H+ concentration in the workup.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Kirill K. Popov, Joanna L. P. Campbell, Ondrej Kysilka, Jan Hosek, Christopher D. Davies, Milan Pour, Pavel Kocovsky
Summary: In this study, Aldimines generated from various aldehydes and amines can be reduced using trichlorosilane in the presence of dimethylformamide as an organocatalyst. The reaction tolerates a wide range of functional groups and offers advantages over traditional methods in terms of efficiency and chemoselectivity. The use of DMA as a greener alternative to DMF is also explored.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Applied
Lenka Benesova, Jan Klouda, Eva Blahova, Karel Nesmerak, Pavel Kocovsky, Jana Nadvornikova, Petr Bartak, Jana Skopalova, Karolina Schwarzova-Peckova
Summary: A simple electrochemical method for quantifying cholesterol in dairy products was evaluated in this study. The method showed close agreement with GC-MS and outperformed HPLC-UV in terms of performance.
Article
Engineering, Electrical & Electronic
Simas Macionis, Dalius Gudeika, Dmytro Volyniuk, Malek Mahmoudi, Jurate Simokaitiene, Viktorija Andruleviciene, Murad Najafov, Rita Sadzeviciene, Sigitas Stoncius, Juozas V. Grazulevicius
Summary: The synthesis and optoelectronic properties of four thioxanthone derivatives with different electron-donating abilities are reported. These compounds form molecular glasses and exhibit different charge transport and luminescence properties, as well as various electroluminescence colors in organic-light-emitting diodes.
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Yi Du, Adelaide Lunga, Aleksandr E. Rubtsov, Andrei Malkov
Summary: This study reports a greener and step-economical synthesis of N-acetylcolchinol using electrochemical reactions instead of transition metals or hazardous reagents. The target compound was obtained with high overall yield and enantiomeric purity.
Article
Biochemistry & Molecular Biology
Alexander G. Tkachenko, Natalya M. Kashevarova, Roman Yu Sidorov, Larisa Yu Nesterova, Anna Akhova, Ivan Tsyganov, Vladimir Yu Vaganov, Sergei A. Shipilovskikh, Aleksandr E. Rubtsov, Andrei Malkov
Summary: A synthetic compound called DMNP has been identified as capable of suppressing persistence and eradicating biofilms in Mycobacterium smegmatis, possibly by targeting enzymes like Rel(Msm) and RelZ. This research suggests that DMNP may be a promising lead compound for the development of antimycobacterial drugs.
CELL CHEMICAL BIOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Ahmed M. Sheta, Mohammad A. Mashaly, Samy B. Said, Saad S. Elmorsy, Andrei Malkov, Benjamin R. Buckley
