Article
Chemistry, Applied
Yujiro Hayashi, Masashi Tomikawa, Naoki Mori
Summary: The asymmetric cross-aldol reaction is a synthetically relevant reaction. The reactivity and stereoselectivity of different catalysts were compared for the reaction, and it was found that the proper selection of catalysts can lead to the synthesis of chiral building blocks with high diastereoselectivities and enantioselectivities.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Yujiro Hayashi
Summary: The aldol reaction is a significant carbon-carbon bond-forming reaction in organic chemistry. The use of trifluoromethyl-substituted diarylprolinol as an organocatalyst has been found to be effective in promoting cross-aldol reactions with excellent selectivities.
Article
Chemistry, Organic
Hyoung Min Yeo, Sungmin Kang, Taek Hyeon Kim
Summary: The first chiral proline amide-isothiouronium based bifunctional organocatalyst was developed, showing high to quantitative yields in aldol products with excellent control performance of diastereoselectivities and enantioselectivity.
TETRAHEDRON LETTERS
(2021)
Article
Chemistry, Organic
Heena Inani, Avtar Singh, Meeta Bhati, Kiran Kumari, Alexander S. Kucherenko, Sergei G. Zlotin, Srinivasan Easwar
Summary: The proline-histidine dipeptide laid the groundwork for the construction of three new ion-tagged organocatalysts, utilizing the imidazole moiety of histidine for generating quaternary species. A comparative investigation of the catalysts in the enamine-mediated direct asymmetric aldol reaction revealed contrasting features, particularly under aqueous conditions. The best-performing catalyst was also used for preparing derivatives and achieving desymmetrization.
SYNTHESIS-STUTTGART
(2021)
Article
Chemistry, Organic
Axel Leblond, Ines Houari, Yann Beauxis, Karine Leblanc, Erwan Poupon, Mehdi A. Beniddir
Summary: In this study, an unconventional strategy was used to mimic the catalytic conditions of ketosterase, leading to the successful synthesis of nesteretal A and its analogues.
Article
Engineering, Environmental
Celine Demeese, Clara Lods, David-Alexandre Buisson, Edmond Gravel, Irishi N. N. Namboothiri, Eric Doris
Summary: A proline analog assembled on carbon nanotubes was utilized as a heterogenized catalyst in asymmetric aldol reactions, showing high efficiency, good enantioselectivity, and sustainability using pure water as the solvent. The catalyst operates with low loadings and can be recycled without loss of performance, resulting in aldol products with yields up to 99% and enantiomeric excesses up to 98%.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Stuart C. D. Kennington, Saul F. Teloxa, Miguel Mellado-Hidalgo, Oriol Galeote, Sabrina Puddu, Marina Bellido, Pedro Romea, Felix Urpi, Gabriel Aullon, Merce Font-Bardia
Summary: A direct and asymmetric aldol reaction of N-acyl thiazinanethiones with aromatic aldehydes catalyzed by chiral nickel(II) complexes was reported. The reaction gives high yields of O-TIPS-protected anti-aldol adducts with remarkable stereocontrol and atom economy. The removal of the achiral scaffold provides enantiomerically pure intermediates with synthetic interest for producing anti-alpha-amino-beta-hydroxy and alpha,beta-dihydroxy carboxylic derivatives, with theoretical calculations explaining the observed high stereocontrol.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
David Guzman Rios, Miguel A. Romero, Jose A. Gonzalez-Delgado, Jesus F. Arteaga, Uwe Pischel
Summary: The [Ru(bpy)2(Nor)2]2+ complex is an efficient catalyst for the aldol reaction of acetone with activated benzaldehydes in a buffered aqueous solution. The role of the metal as an activator for nornicotine organocatalyst ligands enhances catalytic activity by about 4.5 times compared to free nornicotine. The study provides insights into the synergistic effect of organic catalysts and metals.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Dattatraya N. Bhangare, Rohit G. Shinde, Pushpalata D. Pawar, Milind D. Nikalje, Mahendra N. Lokhande
Summary: This method utilizes Sc(OTf)(3) as a catalyst and (-)-menthol as a chiral auxiliary to achieve remarkable diastereoselectivity in the asymmetric aldol reaction. It offers mild reaction conditions, high yields, and excellent diastereoselectivity with a variety of substituted aromatic aldehydes. Sc(OTf)(3) demonstrates excellent diastereoselectivity at -45 degrees C under different reaction conditions.
JOURNAL OF HETEROCYCLIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Jae Ho Shim, Ji Yeon Lee, Hyeon Soo Kim, Deok-Chan Ha
Summary: The study developed a catalyst with N-selectivity for the nitroso aldol reaction, using a quantum calculation. The reaction mechanism was determined and optimized, resulting in a high yield of the product with high enantioselectivity. The catalyst provides a less expensive and more environmentally friendly alternative for the reaction.
Article
Chemistry, Multidisciplinary
Yu Wang, Chengyi Wang, Qipeng Cheng, Yu Su, Hongyu Li, Rui Xiao, Chunxia Tan, Guohua Liu
Summary: The development of a combination enzyme and organocatalyst for aqueous sequential organic transformation is environmentally friendly and overcomes the drawback of only a single methodological approach. The integrated laccase and proline as a chemo-enzymatic co-catalyst system enables efficient oxidation/aldol enantioselective sequential reaction, providing various 1,2-diastereoisomeric chiral beta-hydroxy ketones with acceptable yields and high enantio-/diastereoselectivities.
Article
Chemistry, Organic
E. H. Nisala Fernando, Jose Cortes Vazquez, Jacqkis Davis, Weiwei Luo, Vladimir N. Nesterov, Hong Wang
Summary: The formation of enamine from primary arylamines was studied and confirmed, with the necessity of a radical quencher for detection. A direct synthesis of alpha-enaminones from primary arylamines and ketones was developed, and a mechanistic investigation suggested the involvement of an amine radical cation. The reactivity and utility of alpha-enaminones were explored, showing different properties from enamines and advancing understanding in organic chemistry.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Ryoga Hikawa, Mio Shimogaki, Taichi Kano
Summary: Novel threonine-derived amino sulfonamide organocatalysts were developed and successfully applied to asymmetric aldol reactions. The reactions produced anti-aldol adducts with high diastereo- and enantioselectivity when catalyzed by threonine-derived tosylamide, and syn-aldol adducts were obtained when using threonine-derived triflamide catalyst in reactions between alpha-siloxyacetone and aromatic aldehydes. In both cases, a significant improvement in diastereoselectivity was observed compared to threonine-derived carboxylic acid catalyst.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Yuichiro Kawamoto, Naoki Noguchi, Daiki Ozone, Toyoharu Kobayashi, Hisanaka Ito
Summary: Chiral quaternary carbon-containing bicyclic compounds with carbonyl functionalities were efficiently synthesized through asymmetric intramolecular aldol reactions using organocatalysts. Different types of catalysts were used to construct different bicyclic systems.
TETRAHEDRON LETTERS
(2021)
Article
Chemistry, Organic
Luis C. Misal Castro, Ibrahim Sultan, Kohei Nishi, Hayato Tsurugi, Kazushi Mashima
Summary: A new method for preparing multifunctionalized indole derivatives under neutral conditions was developed using an organocatalytic system involving 4,4'-bipyridyl to activate the B-B bond of B(2)nep(2). This protocol allows for a wide range of indole synthesis and shows high compatibility with different functional groups.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Chada Raji Reddy, Ketan Wadekar, Karna Nair, Y. Lakshmi Prapurna
Summary: A new approach for synthesizing benzofurans from non-aromatic precursors is reported. The method involves sequential DBU-mediated cycloisomerization for furanylation followed by benzene ring construction via oxidative aromatization. The reaction has advantages such as atom- and pot-economy, simple reaction conditions, easy preparation of starting materials, and access to diverse substituted benzofurans.
SYNTHESIS-STUTTGART
(2022)
Article
Chemistry, Organic
Chada Raji Reddy, Siddique Z. Mohammed, Paridala Kumaraswamy, Roshan Chandrakant Kajare, Amol D. Patil, V. S. Rao Ganga, Andhavaram Ramaraju, Balasubramanian Sridhar
Summary: An effective synthetic approach for the construction of diverse bicyclic fused cyclopentenones from Morita-Baylis-Hillman (MBH) carbonates of propiolaldehydes has been demonstrated. The transformation involves the propargylation of an alkenylamine with an MBH carbonate followed by the Pauson-Khand reaction to yield cyclopentenone fused with aza-cycles having additional functionality.
SYNTHESIS-STUTTGART
(2022)
Article
Biochemistry & Molecular Biology
Nicolas Levoin, Appala Venkata Ramana Murthy, Vennu Narendar, Nangunoori Sampath Kumar, Pasula Aparna, Anagani Kanaka Durga Bhavani, Chada Raji Reddy, Paul Mosset, Rene Gree
Summary: A series of compounds with piperidine-triazole scaffolds were found to have strong affinity for dopamine and sigma receptors, with selectivity towards specific receptors and channels. The lead compound showed agonist activity and suggested the presence of a calcium-binding regulatory site.
BIOORGANIC & MEDICINAL CHEMISTRY
(2022)
Article
Chemistry, Organic
Chada Raji Reddy, Veeramalla Ganesh, Nagender Punna
Summary: Unprecedented domino aza-annulations of (E)-2-en-4-ynyl-acetonitriles with sodium azide under metal-and oxidant-free conditions for the assembly of triazolo-pyridines are accomplished. The developed strategy offers broad substrate scope and demonstrated its synthetic utility via denitrogenative coupling of fused triazoles with different nucleophiles.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Dabbugoddu Brahmaiah, Anagani Kanaka Durga Bhavani, Pasula Aparna, Nangunoori Sampath Kumar, Helene Solhi, Remy Le Guevel, Blandine Baratte, Thomas Robert, Sandrine Ruchaud, Stephane Bach, Surender Singh Jadav, Chada Raji Reddy, Paul Mosset, Nicolas Gouault, Nicolas Levoin, Rene Gree
Summary: Three series of CLK1 inhibitors were designed, synthesized, and tested against CLKs and DYRK1A kinases. A promising derivative 12g was discovered, showing significant inhibition activity against HsCLK1 and HsDYRK1A. Molecular modeling and kinome scan analysis further supported these results, suggesting the potential for developing selective inhibitors in this kinase family.
Article
Chemistry, Multidisciplinary
Chada Raji Reddy, Muppidi Subbarao, Dattahari H. Kolgave, Uprety Ajaykumar, Puthiya Purayil Vinaya
Summary: An efficient and straightforward method for the synthesis of diversified seleno-azaspiro-2,5-cyclohexadienones from N-(4-methoxy aryl)propiolamides using elemental selenium and boronic acids has been demonstrated. This method can also be extended to N-(4-methoxy aryl)propiolates and biaryl ynones to access the corresponding selenylated oxospiro-2,5-cyclohexadienones and spiro[5,5]trienones, respectively.
Article
Chemistry, Multidisciplinary
Jadhav Rahul Dhanaji, Polasani Samatha, Silver Raju, Prathama S. Mainkar, Raju Adepu, Srivari Chandrasekhar
Summary: The aryne insertion reaction with 2-aroyl malonates/cyanoesters leads to the formation of diarylmethane or chromones, depending on the substitution on the aryne ring. Chromones are generated when an electronegative atom is present at the ortho position of arynes, while other arynes undergo a cascade double aryne insertion to form diarylmethanes.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Organic
Chada Raji Reddy, Karna Nair, Amol D. Patil, Ramachandra Reddy Donthiri, Rene Gree
Summary: A novel one-pot base-promoted insertion reaction of indolyl 2-alkynes into a C-C single bond of 1,3-diketones, followed by intramolecular aldol reaction and dehydrative aromatization, has been described. This reaction cascade allows for the construction of 2-indolyl phenols, involving the formation of both C1-C2 and C3-C4 bonds of phenols with a good substrate range. Furthermore, these bifunctional compounds can be used in a novel arylative annulation in the presence of Grignard reagents to provide chromeno-indole frameworks.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Applied
Chada Raji Reddy, Muppidi Subbarao, Anjali Rathaur, Ejjirotu Srinivasu
Summary: This paper reports the Rh(III)-catalyzed cascade oxidative C-H functionalization/aza-annulation of indole and pyrrole-N-carboxamides with 1,3-enynes involving 1,4-rhodium migration. It provides an approach for the synthesis of imidazo[1,5-a]indol-3(2H)-ones from easily accessible substrates. The compatibility of sulfonamides in this method is also demonstrated, leading to the corresponding benzo[d]sultams.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Silver Raju, Palash Ghosh, Kiranmai Nayani, Jupally Prashanth, Balasubramanian Sridhar, Prathama S. Mainkar, Srivari Chandrasekhar
Summary: Cascade aza-Piancatelli reaction and [3+3]/[4+2] cycloaddition reactions can generate octahydro-4H-cyclopenta[b]pyridin-6-one scaffolds. In addition, octahydro-5,7a-epoxycyclopenta[cd]isoindol-4-one frameworks of gracilamine alkaloid and a novel decahydro-1H-dicyclopenta[cd,hi]isoindol-6-one can also be synthesized with excellent regio- and diastereo-selectivities.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Chada Raji Reddy, Uprety Ajaykumar, Dattahari H. Kolgave, Remya Ramesh
Summary: A variety of unactivated N-benzyl acrylamides underwent dearomative ipso-cyclization induced by sulfur-centered radicals in the presence of ceric ammonium nitrate as the oxidant to produce azaspirocycles in good yields. This represents the first report on ipso-dearomatization of N-benzyl acrylamides without substituents at the para-position of the aromatic ring. The reaction conditions are also applicable to substrates with substituents at the para-position such as F, NO2, OMe, OH, and OAc.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Chada Raji Reddy, Ankita Kumari, Suraj Aswale, Amol D. Patil, Y. Lakshmi Prapurna
Summary: The reaction of alkynyl p-quinone methide (pQM) with keto-methylenes through a base-mediated tandem 1,6-addition/annulation sequence, [2 + 3] annulation, affords furans for the first time. Various functionalized furans, including fused derivatives, can be obtained in good to excellent yields under mild reaction conditions. The effectiveness of alkynyl pQMs is demonstrated by their ability to access isoxazoles, pyrazoles via [3 + 2] annulation, and pyridines through [3 + 3] annulation in the presence of different bis-nucleophiles.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Chada Raji Reddy, Uprety Ajaykumar, Amol D. Patil, Remya Ramesh
Summary: A CAN-promoted oxidative ipso-cyclization of unactivated biaryl ynones with S-centered radicals has been developed for the synthesis of spiro[5,5]trienones. The method exhibited excellent regioselectivity towards spirocyclization and tolerated various functional groups. Dearomatization of previously unknown aryl/heteroaryl groups was also achieved. DMSO was employed as a low-toxicity, inexpensive solvent and oxygen source.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Chada Raji Reddy, Veeramalla Ganesh, Nagender Punna
Summary: This article describes a base-mediated unexpected aminative carbo-cyclization of cyano-enynyl esters, generated from Morita-Baylis-Hillman (MBH) acetates of propiolaldehydes, with secondary-amines. This metal-free reaction allows the synthesis of a unique cyclopentenone bearing an exocyclic double bond (cyano-olefin) with high E-selectivity in good yields. The synthetic potential of this annulation was further exemplified by the derivatization of bioactive molecules, a scale-up synthesis and synthetic transformations of the obtained cyclopentenone.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Organic
Kailas V. Preeti, Kailas V. Kallurkar, Prathama S. Mainkar, Raju Adepu, Srivari Chandrasekhar
Summary: A concise route for the synthesis of dihydrobenzo-[j]-phenanthridinones has been developed using an aryne annulation strategy under metal-free reaction conditions. The reaction involves multiple C-C and C-N bond cleavages/formations through Diels-Alder reaction, aromatization-driven C-N bond cleavage, and amide formation.