Article
Chemistry, Organic
Liubo Li, Anton El Khoury, Brennan O. Clement, Patrick G. Harran
Summary: This study describes the re-assignment of configuration previously ascribed to product diastereomers resulting from imidazolidinone-catalyzed conjugate addition, and introduces a modified procedure using a diphenylprolinol catalyst to selectively provide the 'syn' diastereomeric product in high enantiomeric excess on decagram scales.
TETRAHEDRON LETTERS
(2021)
Article
Chemistry, Organic
Khadijah Anwar, Francisco Jose Aguilar Troyano, Ayham H. Abazid, Oumayma El Yarroudi, Ignacio Funes-Ardoiz, Adrian Gomez-Suarez
Summary: Here, we present a highly modular strategy for synthesizing spirocyclic scaffolds from easily available starting materials, such as cyclic ketones and alpha-amino or oxamic acids. The reaction involves a simple Knoevenagel condensation, followed by a cascade Giese-type reaction and base-mediated cyclization, resulting in a wide range of polar spirocyclic products in high yields. Our method allows for easy diversification of the products, thus providing rapid access to libraries of potential drug-like molecules.
Article
Chemistry, Organic
Jinhu Wei, Jie-Sheng Huang, Chi-Ming Che
Summary: The chiral Fe-II(N4) complex developed is an effective chiral Lewis acid for the asymmetric conjugate addition of silyl enol ethers to alpha,beta-unsaturated 2-acyl imidazoles, resulting in high yields and enantioselectivities (up to 99% ee) of chiral 1,5-dicarbonyl synthons and cyclohexenone derivatives.
Article
Chemistry, Multidisciplinary
Oleg Grossmann, Rajat Maji, Miles H. Aukland, Sunggi Lee, Benjamin List
Summary: Strong and confined IDPi catalysts enable highly enantioselective substitutions of cyclic, aliphatic hemiaminal ethers with enol silanes, giving access to 2-substituted pyrrolidines, piperidines, and azepanes with high enantioselectivities. The method exhibits broad tolerance towards various enol silane nucleophiles. Mechanistic studies suggest the involvement of non-stabilized, cyclic N-(exo-acyl)iminium ions with the confined chiral counteranion as intermediates, while computational studies provide transition states that account for the observed enantioselectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Sophi R. Todtz, Cory W. Schneider, Tanmay Malakar, Clare Anderson, Heather Koska, Paul M. Zimmerman, James J. Devery
Summary: Lewis acid-catalyzed carbonyl-olefin metathesis has revealed new behaviors of Lewis acids, particularly the solution behaviors of FeCl3. Adding TMSCl to FeCl3-catalyzed carbonyl-olefin metathesis leads to significant deviations from normal reactivity, mitigating byproduct inhibition and increasing the reaction rate. Quantum chemical simulations suggest the formation of a silylium catalyst that binds to carbonyl groups, with potential utility in carbonyl-based transformations.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Organic
Ryoji Sugiyama, Masahisa Nakada
Summary: A highly enantio- and diastereoselective Mukaiyama-Michael reaction using an enol silane of tert-butyl thiopropionate is described. The yield, diastereomer ratio, and enantiomeric excess were 87%, 27:1, and 91% ee under stoichiometric conditions, while under catalytic conditions, they were 89%, 49:1, and 88% ee, respectively. The highly stereoselective epimerization of the Mukaiyama-Michael reaction product is also described, yielding the product with a 77% yield and a diastereomer ratio of 22:1. A method for synthesizing all four stereoisomers of the product as useful chiral building blocks has been established due to the availability of both enantiomers of the ligand for this reaction.
Article
Chemistry, Multidisciplinary
Jiaqi Tao, Linling Xu, Changbao Pei, Yansong Gu, Yanru He, Xianfei Zhang, Xuewei Tao, Jintang Zhou, Zhengjun Yao, Shifei Tao, Hongjing Wu
Summary: Heteroatom doping, especially with sulfur, can induce strong competition among anions, leading to enhanced dielectric coupling effect and activated defect-induced polarization, resulting in high-performance microwave absorption materials.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Organic
Nariyoshi Umekubo, Tohru Taniguchi, Kenji Monde, Yujiro Hayashi
Summary: Bicyclo[2.2.2]octane derivatives with a quaternary bridgehead carbon were synthesized in nearly optically pure form with excellent diastereoselectivity using diphenylprolinol silyl ether mediated domino Michael/Michael reaction of alpha,beta-unsaturated aldehyde and cyclohex-2-en-1-one containing an electron-withdrawing group at the 3-position. Carbonitrile, alkoxycarbonyl, and sulfonyl substituents proved to be effective electron-withdrawing groups at the 3-position of cyclohex-2-en-1-one.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Subba Rao Polimera, Andivelu Ilangovan, Murugaiah A. M. Subbaiah
Summary: This study discovered that silyl enol ethers can be used as a masked source of saturated ketones to produce beta-aryl enones and their derivatives through dehydrosilylation and subsequent oxidative arylation using Pd-(II) catalysis. Oxygen was found to be an efficient and environmentally friendly oxidant for both dehydrosilylation and arylation. The arylation conditions can be customized to utilize aryl halides as an alternative source of arylation agents. 35 examples were tested with up to 95% yield, and mechanistic studies revealed a cationic Pd-(II)-based catalytic system.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Subba Rao Polimera, Andivelu Ilangovan, Murugaiah A. M. Subbaiah
Summary: Silyl enol ethers were used as a masked source of saturated ketones for the synthesis of β-aryl enones and their derivatives. Through dehydrosilylation and oxidative arylation using arylboronic acids, these compounds were generated in situ using a one-pot relayed Pd-(II) catalysis under base-free conditions. Oxygen was found to be an effective oxidant for both dehydrosilylation and arylation reactions. The arylation conditions could be customized to utilize aryl halides as an alternative source of arylating agents. The study investigated the preparative scope using 35 examples with yields up to 95%, and mechanistic studies suggested a cationic Pd-(II)-based catalytic system.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Ziwei Gu, Li Zhang, Haijun Li, Shanshan Cao, Yanli Yin, Xiaowei Zhao, Xu Ban, Zhiyong Jiang
Summary: Catalytic deracemization is an ideal synthetic strategy with high atom utilization efficiency. This study presents a new platform based on photoredox-neutral catalysis for efficient enrichment of valuable analogues like alpha-amino esters through photocatalysis and chiral Bronsted acid catalysis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Peter-Yong Wang, Itai Massad, Ilan Marek
Summary: The facile and modular access to stereodefined disubstituted aldehyde-derived silyl enol ethers allowed for their successful application in a stereoselective aldol reaction, resulting in excellent yields and diastereomeric ratios. The counter-intuitive stereochemical behavior of this Mukaiyama-aldol reaction is explained by a non-classical open transition state.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Ryoji Sugiyama, Masahisa Nakada
Summary: This article describes an enantioselective formal total synthesis of damsin, a compound isolated from Ambrosia maritima L., a member of the Compositae family. The use of highly enantio- and diastereoselective catalytic Mukaiyama-Michael reaction and subsequent highly stereoselective epimerization enables a shorter synthetic route. Additionally, it is reported that the enolate formed by the reaction of 13-keto sulfone with lithium naphthalenide reacts with methyl cyanoformate to yield a quaternary stereogenic center with high yield and stereoselectivity. This finding expands the synthetic chemistry starting from 13-keto sulfones.
Article
Chemistry, Multidisciplinary
Minami Odagi, Keisuke Hosoya, Kazuo Nagasawa
Summary: The common pentacyclic core structure of Aspidosperma alkaloids was constructed using a sequential ring construction strategy. The B ring was formed through oxidative phenolic coupling of diaryl amine using a hypervalent iodine reagent. Then, the resulting dienone underwent an intra-molecular regioselective aza-Michael reaction to form the E ring. Finally, a 6-exo-trig radical cyclization with V-601 as a radical initiator led to the formation of the D ring with a carbon quaternary stereogenic center at C20.
Article
Chemistry, Multidisciplinary
Masahito Yoshida, Yuhi Okoshi, Hideo Kigoshi
Summary: A concise total synthesis of metacridamides A and B was achieved through repetitive vinylogous Mukaiyama aldol reactions and ynamide-mediated macrolactonization. The spectral data of the synthetic products matched those of the natural compounds, leading to the reassessment of the absolute configuration of the C-9 position as S.
CHEMICAL COMMUNICATIONS
(2023)
Article
Polymer Science
Kai Chen, Chun -Yu Chen, Hsin-Lung Chen, Ryoya Komaki, Nao Kawakami, Takuya Isono, Toshifumi Satoh, Du -Yuan Hung, Ying-Ling Liu
Summary: This study reveals the strong effects of molecular architecture and configuration on the self-assembly behavior of sugar-based block copolymers. The configuration prescribed by the substituted positions of the block chains exerts a significant influence on the formation of hydrogen bonding and the resistance against bending. These findings provide insights into the controlled fabrication of ordered structures in green materials.
Article
Polymer Science
Xiaochao Xia, Tianle Gao, Feng Li, Ryota Suzuki, Takuya Isono, Toshifumi Satoh
Summary: Switchable polymerization has potential for synthesizing sequence-controlled macromolecules similar to natural biopolymers, but is limited to three-and four-component systems. We expanded its scope to five-component systems using a reactivity gradient among 12 monomers. Different copolymerizations were achieved using a catalyst, allowing for the synthesis of gradient and block copolymers. Anhydride reactivity was predicted using 13C NMR chemical shifts. This comonomer library allows for the prediction and preparation of more complex copolymer structures.
Article
Polymer Science
Huan Li, Yingying Li, Yudan Wang, Lijia Liu, Hongxing Dong, Chunhong Zhang, Toshifumi Satoh
Summary: In this study, a Lys-BPEA crosslinker was synthesized using primary amines rich in lysine end groups. An antibacterial self-healing hydrogel (PAA/Lys-BPEA) was prepared by introducing polyamine Lys-BPEA into PAA via ionic bonding and electrostatic interaction. The PAA/Lys-BPEA hydrogel exhibited excellent antibacterial and self-healing properties, making it an ideal choice for the design of smart self-healing devices and antibacterial surface coatings.
Article
Polymer Science
Ryohei Sato, Atsuo Utagawa, Koji Fushimi, Feng Li, Takuya Isono, Kenji Tajima, Toshifumi Satoh, Shin-ichiro Sato, Hiroshi Hirata, Yoshihiro Kikkawa, Takuya Yamamoto
Summary: The redox behaviors of macrocyclic molecules with an entirely pi-conjugated system were investigated in this study. Cyclic P3HT with different degrees of polymerization (DPn) were synthesized, and its unique redox behaviors were compared with linear P3HT. Cyclic P3HT showed a decrease in HOMO level and greater stability during cyclic voltammetry measurement, indicating stronger dicationic properties due to polaron-polaron interactions.
Article
Polymer Science
Li-Chieh Chou, Kiho Matsubara, Kenji Takada, Tatsuo Kaneko, Ryohei Kakuchi
Summary: In this study, adhesive polymers were synthesized using biobased compounds and modified through Passerini-3CR to introduce photoresponsive phenylpropanoid units. These adhesive polymers showed good adhesion properties for quartz plates and the adhesion behaviors were affected by photoirradiation, possibly due to the self-cycloaddition of phenylpropanoid-derived vinyl moieties.
Review
Polymer Science
Kenji Takada
Summary: The use of cinnamic acid is a promising approach for developing biobased plastics to mitigate global warming caused by increasing carbon dioxide levels. Cinnamic acids in plants and microorganisms have been extensively studied for their unique properties, especially their reactivity to UV light. Recent research focused on polyesters synthesized from hydroxycinnamic acid abundant in plants, which exhibit photodeformability and can be converted into high-performance biobased plastics.
Article
Chemistry, Multidisciplinary
Erika Terada, Takuya Isono, Toshifumi Satoh, Takuya Yamamoto, Toyoji Kakuchi, Shinichiro Sato
Summary: Recently, temperature-responsive polymers tethered to oligooxyethylene side chains terminated with alkyl groups were experimentally investigated. Molecular dynamics simulations were used to study aqueous solutions of poly(glycidyl ether)s with different numbers of oxyethylene units. The thermal responses of chain extensions, hydrogen bond recombination, and water-solvation shells were analyzed. The phase-transition temperature was not directly related to the polymer-chain extensions, but the temperature response of the water-solvation shell around the alkyl group showed a noticeable correlation. The relationship between TCRP and TCLP was found to be affected by polymer-chain fluctuation.
Article
Chemistry, Multidisciplinary
Teru Kawazoe, Hikaru Yanai, Yuto Hagiyama, Kazumasa Funabiki, Takashi Matsumoto
Summary: 1,3-Disubstituted N-aryl-2H-isoindoles were synthesized via a cascade reaction of divinyl ethers with substituted anilines in HFIP. The cascade reaction involves a ring-opening step and a 5-exo-tet type ring-closing step. The resulting 2H-isoindoles can be derivatized to high-order nitrogen-containing polycycles.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Hien Thi Phan, Shoko Furukawa, Koto Imai, Hiroya Tomita, Takuya Isono, Toshifumi Satoh, Ken'ichiro Matsumoto
Summary: Bacterial polyhydroxyalkanoate (PHA) synthase PhaC(AR) and its mutated variants were used to synthesize block copolymers with poly(d-lactate) (PDLA) segments. Beneficial mutations N149D and F314H increased the incorporation of D-lactate (LA) units, resulting in the synthesis of P(3HB)-b-PDLA and P(3HHx)-b-PDLA. This study demonstrates a new method for the synthesis of block copolyesters with isotactic PDLA segments from renewable resources using engineered polyester synthase.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Chemistry, Organic
Hikaru Yanai, M. Rosa Marquez, Sara Cembellin, Teresa Martinez del Campo, Pedro Almendros
Summary: An indium-promoted lactonization of (indol-3-yl)-2-oxoacetaldehydes, allowing the synthesis of substituted gamma-methylenebutenolides in water, has been achieved. This process differs from the established reactivity of unsaturated organic halides and carbonyls mediated by metals. The use of water as a medium and the ease of purification make this protocol a convenient and sustainable synthetic strategy. A plausible reaction pathway has been proposed with the aid of density functional theory calculations.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Polymer Science
Yamato Ebii, Yoshinobu Mato, Feng Li, Kenji Tajima, Takuya Yamamoto, Takuya Isono, Toshifumi Satoh
Summary: In this study, multicyclic polystyrene (mc-PS) was successfully synthesized through the cyclopolymerization of alpha,omega-dinorbornenyl end-functionalized PS macromonomers mediated by the Grubbs third-generation catalyst. The number of cyclic units in the obtained mc-PS was controlled by adjusting the macromonomer-to-G3 ratio, with a maximum of 239 units achieved. The developed cyclopolymerization strategy provides a new approach for the synthesis of multicyclic polymers and has significant implications for fundamental studies and material applications.
Article
Chemistry, Multidisciplinary
Babak Kaboudin, Mojtaba Ghashghaee, Haruhiko Fukaya, Hikaru Yanai
Summary: A novel and convenient synthesis method for vinyl phosphonates using an aromatic aza-Claisen rearrangement were developed. The synthetic utility of this method was further examined in a gram-scale synthesis. DFT calculations provided insights into the reaction mechanism.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Yaodong Wang, Yudan Wang, Lijia Liu, Kexiao Sang, Chunhong Zhang, Toshifumi Satoh
Summary: Metal-free catalysts have emerged as an important research focus in catalysis due to the growing concern over heavy metal pollution. In this study, a heterogeneous catalyst, l-Pro-l-Pro-l-Phe-l-Phe-OMe, was synthesized by connecting an aromatic amino acid dipeptide (l-Phe-l-Phe-OMe) with a proline dipeptide (l-Pro-l-Pro) through solid phase synthesis. The catalyst's structure was characterized using SEM, XRD, NMR, and FTIR spectroscopy, with X-ray diffractometry revealing a rod crystal structure. Furthermore, l-Pro-l-Pro-l-Phe-l-Phe-OMe exhibited superior catalytic activity compared to a homogeneous small molecule catalyst (high enantioselectivity, ee > 97%) in heterogeneous asymmetric aldol reactions and demonstrated good recyclability.
REACTION CHEMISTRY & ENGINEERING
(2023)
Article
Chemistry, Organic
Babak Kaboudin, Hesam Esfandiari, Meysam Kakavand, Masoumeh Sohrabi, Elahe Yousefian Amirkhiz, Abdollah Neshat, Teru Kawazoe, Haruhiko Fukaya, Hikaru Yanai
Summary: A novel and convenient method for the N-formylation reaction of amines with DMF as a formylating agent has been developed using a catalytic amount of diethyl phosphite/imidazole. Diethyl phosphite plays a significant role as a nucleophilic catalyst in this conversion. The method has a broad substrate scope and provides good to excellent yields of various N-formyl products. In addition, the reaction of o-phenylenediamines with DMF gives benzimidazoles, and N-sulfonyl amidines are obtained in good to excellent yields by reacting sulfonamides with DMF under similar conditions.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Organic
Babak Kaboudin, Hesam Esfandiari, Meysam Kakavand, Masoumeh Sohrabi, Elahe Yousefian Amirkhiz, Abdollah Neshat, Teru Kawazoe, Haruhiko Fukaya, Hikaru Yanai
Summary: A novel and convenient method for the N-formylation reaction of amines using DMF as a formylating agent has been developed, with diethyl phosphite/imidazole as a catalytic system. This method exhibits broad substrate scope and allows for the synthesis of N-formyl products in good to excellent yields. Additionally, N-acetylation reactions and the synthesis of N-sulfonyl amidines were achieved using DMA and sulfonamides, respectively.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Review
Chemistry, Multidisciplinary
Dan He, Yawen Li, Fuwen Zhao, Yuze Lin
Summary: High trap density in organic solar cells leads to localized charge carriers and reduced carrier lifetime, limiting device efficiency. This feature article summarizes the recent advances of trap suppression by material design and device engineering.
CHEMICAL COMMUNICATIONS
(2024)
Review
Chemistry, Multidisciplinary
Olivier Monfort, Arshitha Madhusudhan, Martin Motola
Summary: This article presents the advantages of coupling photocatalysis and Fenton-based processes for environmental remediation and discusses their synergy. It critically examines the simultaneous triggering of these two processes and provides insights into research approaches. The study aims to enhance understanding of this complex process and highlight the potential integration of new catalysts in current wastewater treatment technology.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Manideepa Dhar, Chittaranjan Mishra, Avijit Das, Uttam Manna
Summary: An approach of 'polymerization of monomers in its aggregated form' has been introduced to tailor the water wettability of fibrous and porous substrates, achieving hydrophobicity to superhydrophobicity transition, as well as patterned wettability. This facile chemical method provides a durable coating with adjustable and patterned wettability for various potential applications.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Saswat Ranjan Bhoi, Chhanda Debnath, Shikha Gandhi
Summary: In this article, a novel catalytic reaction using Pd(0) and Bronsted acid is reported for the synthesis of biologically important imidazolidinone-fused N-heterocycles through redox-neutral intramolecular N-allylation of indoles and pyrroles with alkynes. This atom-economical method is applicable to a wide range of substrates and eliminates the need for leaving groups or oxidizing agents commonly used in traditional allylation reactions.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Longkun Chen, Mingshuai Zhang, Meichen Liu, Zhuoyuan Liu, Yuetong Qiu, Zhilai Zhang, Fuchao Yu, Jiuzhong Huang
Summary: In this study, an efficient Rh(III)-catalyzed selective mono- and dual-C-H bond functionalization/cyclization with iodonium ylide as the sole coupling partner was demonstrated. Fused benzodiazepine skeletons were obtained in excellent yields, providing an improved approach to dual C-H unsymmetrical functionalization.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Alice Kennett, Sven Epple, Gabriella van der Valk, Irene Georgiou, Evelyne Gout, Romain R. Vives, Angela J. Russell
Summary: This study presents the design and synthesis of sulfated disaccharide inhibitors based on IdoA(2S)-GlcNS(6S), which showed potent inhibition of Sulf-2. The results suggest that IdoA(2S)-GlcNS(6S) is the shortest fragment size required for effective inhibition of Sulfs, and a trisulfated disaccharide is identified as the minimal fragment size of heparan sulfate for effective endosulfatase inhibition.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Mauro Garbini, Andrea Brunetti, Riccardo Pedrazzani, Magda Monari, Massimo Marcaccio, Giulio Bertuzzi, Marco Bandini
Summary: The self-adaptability of galvanostatic electrolysis was found to be helpful in a multistage chemo- and diastereoselective electrochemically promoted cyclodimerization of chalcones. Through a series of reductive events, densely functionalized cyclopentanes with five contiguous stereocenters were obtained (25 examples, yields up to 95%, dr values up to >20:1). Further experimental and electrochemical investigations indicated the crucial role of dynamic kinetic resolution of the aldol intermediate in the reaction mechanism.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Dhananjay S. Nipate, Neha Meena, Prakash N. Swami, Krishnan Rangan, Anil Kumar
Summary: In this study, the synthesis of functionalized benzo[a]phenazines and indazolo[2,3-a]quinolines was achieved through Rh(III)-catalyzed oxidative annulation of 2-arylquinoxalines and 2-aryl-2H-indazoles with allyl alcohols. The method showed a wide substrate scope, excellent functional group tolerance, good to high yields of annulated products, and the capability for scaled-up synthesis. A tentative mechanism of the annulation reaction was proposed based on a preliminary mechanistic investigation.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Ruonan Zhang, Abudukadi Tudi, Xia Yang, Xuping Wang, Zhihua Yang, Shujuan Han, Shilie Pan
Summary: A new lead tellurium borate material with a unique fundamental building block [B4O10] was synthesized and found to exhibit high birefringence. The structure-property relationship was discussed using first-principles calculations.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Amresh Kumar Singh, Baishali Thakurta, Anupam Giri, Monalisa Pal
Summary: This study introduces three key concepts for the quick synthesis of large-scale high-quality 2D materials films and their utilization in device fabrication.
CHEMICAL COMMUNICATIONS
(2024)
Article
Chemistry, Multidisciplinary
Reina Hagiwara, Shun Nishimura, Kosuke Okeyoshi
Summary: A copolymer-conjugated nanocatalytic system has been developed to improve electron transfer and enhance photoinduced H2 generation.
CHEMICAL COMMUNICATIONS
(2024)
