Article
Chemistry, Applied
Eugenia Marques-Lopez, Isaac G. Sonsona, Miryam Garces-Marin, M. Concepcion Gimeno, Raquel P. Herrera
Summary: In this study, the potential of phosphites as nucleophiles for the asymmetric synthesis of chiral chromene derivatives was explored. By employing asymmetric organocatalyzed phospha-Michael addition, chiral chromenylphosphonates were synthesized using a bifunctional squaramide. The optimized protocol provided good reactivity with yields of up to 95% and chiral products with an enantiomeric excess of up to 98%.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Organic
Juan A. Venegas-Nava, Francisco Yuste, Ruben Sanchez-Obregon
Summary: A transition metal free synthesis of tetrasubstituted allenes is reported, where the reaction between alpha,beta-unsaturated esters and ortho-sulfinylated benzyl-propargylic carbanions yields tetrasubstituted chiral allenes in good yields and with good isomeric ratios.
TETRAHEDRON LETTERS
(2021)
Article
Chemistry, Organic
Hengqian Song, Jiacheng Song, Lihong Yan, Weigang He, Pengyan Wang, Yuanzhen Xu, Hongbo Wei, Weiqing Xie
Summary: The asymmetric synthesis of (-)-dihydrospirotryprostatin B has been achieved in 8 longest linear steps from commercially available amino acids. The key step involves the tandem Michael addition of oxindole derived from dipeptide diketopiperazine to alkynone, leading to the rapid construction of the spiro [pyrrolidine-3,3'-oxindole] scaffold.
TETRAHEDRON LETTERS
(2021)
Article
Chemistry, Organic
Hanlin Yang, Zhipeng Ning, Shiyu Wang, Jiazhu Li, Zu-Li Wang, Wei-Li Wang, Xin-Ming Xu
Summary: An efficient method was developed for constructing diverse seven-membered N-heterocyclic rings under mild conditions. The resulting products contained multiple reactive sites, making them valuable intermediates for synthesizing other N-heterocyclic compounds.
TETRAHEDRON LETTERS
(2021)
Article
Chemistry, Physical
Alexey A. Tsygankov, Denis Chusov
Summary: By using a fluoride anion source, well-known transition metal catalysts can be transformed into high-performance versions, increasing catalytic activity, particularly in reactions such as asymmetric cyanation of aldehydes, asymmetric Michael addition, and synthesis of cyclic carbonates.
Article
Chemistry, Multidisciplinary
Karem J. Sabah, N. Idayu Zahid, Rauzah Hashim
Summary: A series of new mix aza- and thia-macrocyclic glycolipids have been synthesized and studied for their enantiomeric selectivity, with the galactose aza-crown ether-based glycolipid 21 proving to be the most effective catalyst with 90% ee in the enantioselective Michael addition reaction.
RESEARCH ON CHEMICAL INTERMEDIATES
(2021)
Article
Chemistry, Multidisciplinary
Zubeda Begum, Haruka Sannabe, Chigusa Seki, Yuko Okuyama, Eunsang Kwon, Koji Uwai, Michio Tokiwa, Suguru Tokiwa, Mitsuhiro Takeshita, Hiroto Nakano
Summary: Simple primary beta-amino alcohols act as efficient organocatalysts in the asymmetric Michael addition of beta-keto esters with nitroalkenes, producing highly pure chiral Michael adducts. The choice of catalyst and reaction temperature determines the enantiomeric outcome of the adducts.
Article
Chemistry, Physical
Yongkang Song, Jian Wang, Shaomin Deng, Guohua Liu, Tanyu Cheng
Summary: Domino catalytic reactions are a powerful strategy for synthesizing complex and high-value compounds. In this study, a domino enantioselective Michael addition/cyclization process, catalyzed by inexpensive and readily available quinidine, was developed. The reaction proceeded smoothly under mild conditions at room temperature within 2 hours, affording chiral 1,4-dihydro-pyridine containing benzosultams in good yields (up to 95%) and excellent enantioselectivities (up to 99% ee).
MOLECULAR CATALYSIS
(2022)
Article
Chemistry, Applied
Irma Garcia-Monzon, Jorge Borges-Gonzalez, Tomas Martin
Summary: The heterogenization of homogeneous catalysts onto a solid support is a crucial step towards sustainable chemistry. In this study, we developed a series of polymer-supported tetrahydropyran-based hybrid dipeptides as active catalysts for the enantioselective Michael addition of aldehydes to beta-nitrostyrenes. The optimal anchor position and orientation between the catalyst and solid support, as well as the linker length, were carefully designed to enhance the catalytic efficiency. These supported catalysts exhibited high yields and enantiomeric excesses, and detailed deactivation studies provided important insights for prolonging their useful life.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Organic
Ruslan A. Kovalevsky, Maxim Smirnov, Alexander S. Kucherenko, Kseniya A. Bykova, Elizaveta Shikina, Sergei G. Zlotin
Summary: In this study, 2-nitroallylic carbonates were used for the first time as promising biselectrophilic C3 synthons. They reacted with kojic acid derivatives in a bifunctional squaramide catalyzed asymmetric domino reaction, yielding nitro compounds that contain two hydroxypyranone units. The reaction products undergo noncatalytic epimerization at the carbon atom next to the nitro group. A plausible mechanism of the epimerization based on reversible formation of intermediate aci-nitro compound is proposed. The double addition products were transformed into configurationally stable acetates and chiral nitro glutarates, which are promising precursors for chiral amino glutaric acid derivatives.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Leman Alkan, Ozgur Alver, Stephen T. Astley, Eralp Kulan, Cemal Parlak
Summary: The tandem Knoevenagel-Michael addition of diethyl malonate to nitro-substituted benzaldehydes was found to proceed in a mild and convenient process. The H-1 NMR spectra of the products showed significant changes according to the position of the nitro group. Conformational analysis calculations confirmed the presence of a structure containing a mirror plane near the ground state in all cases. However, increased steric crowding in the meta and ortho substituted products resulted in decreased rotational freedom of the ethyl substituents. Molecular orbital calculations predicted a higher electrophilic reactivity of the ortho nitro substituted product, consistent with the observed increase in steric stress.
JOURNAL OF MOLECULAR STRUCTURE
(2022)
Article
Chemistry, Physical
Yiqi Ren, Maodi Wang, Qihua Yang, Junfa Zhu
Summary: The development of chiral solid catalysts using unconventional strategies is crucial for efficient heterogeneous asymmetric catalysis. The study presents a chiral solid catalyst, chiral diamine modified Ni/SiO2, for asymmetric Michael addition. The experimental results demonstrate that the peripheral Ni sites in close contact with SiO2 support are likely to be the active sites.
Article
Chemistry, Multidisciplinary
Sebastian Frankowski, Justyna Kowalska, Anna Albrecht
Summary: A novel method has been described for the preparation of enantiomerically enriched pyridine derivatives using 2-pyridylacetic acids as valuable synthons in an asymmetric fashion. The synthesis based on iminium activation using a chiral aminocatalyst successfully controlled the stereochemical outcome of the transformation.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Organic
Prasenjit Gayen, Prasanta Ghorai
Summary: A highly chemoselective 1,2-addition of thiols with 2-isothiocyanatochalcones followed by an enantioselective intramolecular thia-Michael addition cascade has been developed for the synthesis of enantioenriched [1,3]-benzothiazine derivatives. The squaramide catalyst derived from cinchona provides excellent yield and enantioselectivity with a wide range of substrates. Furthermore, this strategy can be extended to access enantioenriched organophosphorus-substituted [1,3]-benzothazines using diphenylphosphine oxide nucleophile.
Article
Chemistry, Applied
Gianluca Casotti, Vincenzo Rositano, Anna Iuliano
Summary: Stabilised arylzinc iodide prepared by direct insertion of zinc into aryl iodides, were successfully applied as nucleophiles in the Hayashi Rh-catalysed enantioselective conjugate addition to enones, with high yields and 99% ee of the addition product. The general applicability of the protocol was confirmed by using different arylzinc iodides and enones, as well as organometallic reagents with both halogen and electrophilic groups.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Organic
Fariba Golpayegani, Zohreh Mirjafary, Hamid Saeidian, Javad Mokhtari
Summary: This study investigated ketene derivatives with cyclopropene and methylenecyclopropene substituents as powerful carbon superbases using theoretical calculations, revealing that the protonation of these compounds can lead to new neutral organic bases with high proton affinities. The basicity of the designed ketenes was enhanced by substituting electron-releasing groups on the molecular framework, and aromaticity indices like nucleus-independent chemical shift and harmonic oscillator model were utilized to explain the basicity of ketenes.
JOURNAL OF PHYSICAL ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Applied
Masomeh Mahmoudi, Hamid Saeidian, Zohreh Mirjafary, Javad Mokhtari
Summary: In this study, a memantine release system based on polycaprolactone nanocapsules (MEM@PCL) was prepared for the first time, with an encapsulation efficiency of 80% as measured by high-performance liquid chromatography analysis. Physicochemical stability studies over 40 days demonstrated that the nanocapsules remained stable in solution without aggregation.
JOURNAL OF POROUS MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Baharak Farzin, Hamid Saeidian, Zohreh Mirjafary, Javad Mokhtari Aliabad
Summary: Density functional theory (DFT) calculations were performed on a new set of organic Bronsted acids based on the 9H-fluorene scaffold, determining their optimal structures, acidity, and tautomerization processes. The acidity of the designed compounds was calculated using computational methods, with some compounds found to be superacids. Aromaticity indices and charge distribution analysis were also conducted for the designed compounds and their conjugate bases.
STRUCTURAL CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Zohreh Esmaeeli, Mohammad Reza Khodabakhshi, Zohreh Mirjafary, Hamid Saeidian
Summary: In this study, 12 new dispiroheterocycles containing aurone scaffold were successfully synthesized with high yields through a three-component 1,3-dipolar cycloaddition reaction. The comparison between experimental and theoretical results shed light on the regioselectivity of the reaction.
STRUCTURAL CHEMISTRY
(2022)
Article
Multidisciplinary Sciences
Ewa D. Raczynska, Jean-Francois Gal, Pierre-Charles Maria, Hamid Saeidian
Summary: This study investigates the gas-phase basicity enhancement of nitriles through theoretical methods and identifies the push-pull effect of cyclopropenimine and methylenecyclopropene, as well as their derivatives. The protonation of the cyano group is found to be favored, and strong electron donor X substituents exhibit similar push-pull effects in the two pi-systems. The calculated proton affinities enrich the gas-phase basicity scale of nitriles to around 1000 kJ mol(-1).
Article
Chemistry, Inorganic & Nuclear
Elham Afzali, Zohreh Mirjafary, Azim Akbarzadeh, Hamid Saeidian
Summary: A novel nanoreactor containing well-distributed Cu (II) ions was developed for azide-alkyne cycloaddition reaction, resulting in the synthesis of 1,4disubstituted-1,2,3-triazole derivatives with excellent yields. The synthesized nanocatalyst has high surface area and appropriate pore size, along with good reusability features.
INORGANIC CHEMISTRY COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Zohreh Esmaeeli, Mohammad Reza Khodabakhshi, Zohreh Mirjafary, Hamid Saeidian
Summary: A new family of 1, 2, 3-triazole-based benzodiazepines has been successfully synthesized by the Huisgen [3+2] dipolar cycloaddition reaction in aqueous medium, with mild reaction conditions, excellent yields, and environmentally-friendly features. Density functional theory calculations were conducted on the characterized structure 6a, providing structural, electronic, and thermodynamic data which were further interpreted using computational methods.
JOURNAL OF MOLECULAR STRUCTURE
(2021)
Article
Engineering, Environmental
Masomeh Mahmoudi, Hamid Saeidian, Zohreh Mirjafary, Javad Mokhtari
Summary: A 7-MEOTA delivery system based on polycaprolactone nanocapsules was prepared and investigated, showing stable physico-chemical properties with controlled drug release. The drug amount loaded in nanocapsules was estimated at 65%, with spherical nanoparticles free of aggregation. In vitro release experiments indicated controlled release of 7-MEOTA from the nanocapsules, following Fick's law of diffusion.
JOURNAL OF POLYMERS AND THE ENVIRONMENT
(2022)
Article
Biochemical Research Methods
Seyed Esmaeil Hosseini, Sajjad Mousavi Faraz, Mohammad Taghi Naseri, Davood Ashrafi, Hamid Saeidian
Summary: This study prepared a new category of selenophosphorus compounds using microsynthetic protocols and investigated their fragmentation pathways using mass spectrometry. The results revealed interesting fragmentation pathways, highlighting the importance of this research in identifying CWC-related chemicals during on-site inspection and off-site analysis.
RAPID COMMUNICATIONS IN MASS SPECTROMETRY
(2022)
Article
Chemistry, Physical
Fariba Golpayegani, Zohreh Mirjafary, Javad Mokhtari Aliabad, Hamid Saeidian
Summary: The study revealed that the basicity of phosphaallenes in the gas phase can be enhanced by introducing electron-donating substituents on the ring, making them potential candidates for strong neutral organic superbases and hyperbases.
COMPUTATIONAL AND THEORETICAL CHEMISTRY
(2021)
Article
Physics, Atomic, Molecular & Chemical
Masomeh Eskandari, Sajjad Mousavi Faraz, Seyed Esmaeil Hosseini, Shahram Moradi, Hamid Saeidian
Summary: The mass spectral data of a new group of Novichok organophosphorus nerve agent derivatives were studied, and the fragmentation pathways were proposed and confirmed using deuterated analogs and DFT calculations. Several new fragmentations and rearrangements were observed. The findings from this study are helpful in detecting CWC-related chemicals during on-site and/or off-site inspection.
INTERNATIONAL JOURNAL OF MASS SPECTROMETRY
(2022)
Article
Chemistry, Multidisciplinary
Arjang Jalezadeh, Zohreh Mirjafary, Morteza Rouhani, Hamid Saeidian
Summary: Calycopetrin and xanthomicrol, extracted from plants, are polymethoxylated flavones with extraordinary biological properties. Their structural, electronic, and spectral data were obtained using computational methods and their antioxidant properties and reactivity with oxygen radicals were evaluated.
STRUCTURAL CHEMISTRY
(2022)
Article
Biochemistry & Molecular Biology
Ewa D. Raczynska, Jean-Francois Gal, Pierre-Charles Maria, Ghulam Sakhi Sakhawat, Mohammad Qasem Fahim, Hamid Saeidian
Summary: This work investigates the gas-phase basicity of two series of nitriles and analyzes their isomeric phenomena and substituent effects. By calculating the microscopic and macroscopic gas-phase basicity parameters, the alkalinity properties are predicted.
Article
Biochemistry & Molecular Biology
Zohreh Mirjafary, Mahdieh Mohammad Karbasi, Parsa Hesamzadeh, Hamid Reza Shaker, Asghar Amiri, Hamid Saeidian
Summary: A series of 1,2,3-triazole derivatives based on benzothiazole were synthesized using a simple and green method. The synthesized compounds showed promising anti-inflammatory and inhibition activities. ADMET analysis revealed two molecules with potential for drug development.
Article
Chemistry, Inorganic & Nuclear
H. Ahankar, A. Ramazani, H. Saeidian, K. slepokura, T. Lis
Summary: An efficient method for the synthesis of a highly substituted pyrrolidinone derivative was developed, and the structure was confirmed through various spectroscopic techniques and single crystal X-ray analysis. Comparison with known compounds revealed insight into the molecular dimers formed in the solid state. Calculations using DFT were in agreement with experimental data, verifying the synthesized product structure.
JOURNAL OF STRUCTURAL CHEMISTRY
(2021)
