Article
Chemistry, Organic
Mingzhong Cai, Chengkai Luo, Caifeng Xu, Bin Huang
Summary: Pd(2)dba(3)/XPhos in PEG-2000 has been shown to be a highly stable and efficient catalyst for the borylation of aryl chlorides, delivering a wide variety of aryl boronates in good yields with high functional group tolerance at 110 degrees C. The system allows for easy isolation of crude products through simple extraction of the reaction mixture with cyclohexane, and both the catalyst and system can be recycled and reused more than six times without loss of efficiency.
SYNTHESIS-STUTTGART
(2022)
Article
Chemistry, Multidisciplinary
P. Veeraraghavan Ramachandran, Henry J. Hamann, Sukriti Mishra
Summary: A rapid synthesis of aminoboranes from amine-boranes utilizing an iodination/dehydroiodination sequence is described. It has been applied to a one-pot palladium-catalyzed conversion of iodo- and bromoarenes to the corresponding boronates, and allows for recovery of the utilized amine.
Article
Chemistry, Organic
Shaikh Samser, Priyabrata Biswal, Sushanta Kumar Meher, Krishnan Venkatasubbaiah
Summary: The one-pot synthesis of Robinson annulated 3-aryl-cyclohexenones from allyl alcohols and ketones using palladium catalyst is reported. Long chain aliphatic or aryl substitutions at the C1 position of allyl alcohol lead to the formation of 1,5-diketone products. This method eliminates the need for highly electrophilic vinyl ketones, making the reaction simpler.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
Article
Chemistry, Organic
Pratik Yadav, Sasmita Das, Mariko Saito, Todd Evans, Bhaskar C. Das
Summary: In this study, a new protocol for one-pot borylation/arylation of 4-chloroqunolines is described. The reaction proceeds through a palladium catalyzed one-pot two step process, resulting in the synthesis of C-4 arylated quinolines. This method provides access to various structurally interesting and pharmaceutically relevant compounds with simple and efficient conditions. Additionally, it offers a new synthetic protocol for the functionalization of quinolines at the C-4 position, which is encountered in various quinoline based drugs and biologically important scaffolds.
TETRAHEDRON LETTERS
(2023)
Article
Chemistry, Organic
Kazuki Matsuo, Eiji Yamaguchi, Akichika Itoh
Summary: This study investigates the photoinduced C-X borylation reaction of aryl halides via the formation of a halogen-bonding (XB) complex using 2-naphthol as an XB acceptor. The method is chemoselective and tolerant to a broad range of functional groups, providing a concise route to corresponding boronate esters. Mechanistic studies reveal that the formation of the XB complex between aryl halide and naphthol acts as an electron donor-acceptor complex, generating aryl radicals through photoinduced electron transfer.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Xiaofang Hu, Zeen Qiao, Li Zhang, Jinzhong Zhao, Ya-Zhou Liu, Jiangang Zhang, Xiaofeng Ma
Summary: A one-pot protocol to access 4-substituted dibenzothiophene (DBT) from dibenzothiophene-5-oxide (DBTO) was developed via a sulfoxide directed C-H metalation/B2Pin2 mediated reduction/Suzuki coupling cascade process. The method exhibited high yields and a proposed mechanism. Additionally, the application of this method in synthesizing luminescent materials was demonstrated.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Hongyan Lin, Ziling Zhou, Xiaopeng Ma, Qingqing Chen, Hongwei Han, Xiaoming Wang, Jinliang Qi, Yonghua Yang
Summary: The study presents a green method for obtaining aryl nitriles from aromatic aldehyde in water, utilizing water as a solvent instead of harmful chemical reagents. Twenty-five aryl nitriles were conveniently synthesized with minimal pollution to the environment. The reaction mechanism was further confirmed by capturing intermediates, aldoximes.
Article
Chemistry, Multidisciplinary
Jakub Szyling, Aleksandra Szymanska, Jedrzej Walkowiak
Summary: An efficient and facile one-pot protocol to access enynylboronates via a Pt-catalyzed diboration/protodeboration strategy has been developed for various silyl-substituted symmetrical and unsymmetrical 1,3-diynes, leading to π-conjugated organoboron compounds with excellent regio- and stereoselectivity.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Yudha P. Budiman, Sabine Lorenzen, Zhiqiang Liu, Udo Radius, Todd B. Marder
Summary: This study presents an efficient catalytic C-Cl borylation method for di-ortho-fluorinated aryl chlorides using a combination of Pd(dba)(2) and SPhos as ligand, conducted under base-free conditions. The resulting aryl boronate products are sensitive to base.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Physical
Man Ho Tse, Rong-Lin Zhong, Fuk Yee Kwong
Summary: In this study, a general Pd-catalyzed Miyaura borylation of sterically hindered aryl chlorides was achieved using a tailor-made phosphine ligand. The success of this reaction demonstrated the possibility of coupling highly sterically congested electrophilic partners and showed good functional group compatibility. The ligand-enabled C-B bond formation could provide fundamental knowledge for developing catalyst systems suitable for other highly sterically hindered cross-coupling reactions.
Article
Chemistry, Organic
Kazuki Tomota, Yuki Izumi, Kazuki Nakanishi, Masaaki Nakamoto, Hiroto Yoshida
Summary: A direct and transition metal-free method for the installation of B(dan) into organic frameworks has been developed. Heteroaryl-H bonds can be transformed into heteroaryl-B(dan) bonds through deprotonation. The resulting heteroaryl-B(dan) compounds, which are typically difficult to access, can undergo direct Suzuki-Miyaura coupling. The method has also been demonstrated to be applicable to silicon nucleophiles, leading to the formation of Lewis acidity-diminished stable silyl-B(dan) and -B(aam) in one pot.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Applied
Shan Shan Ng, Zicong Chen, On Ying Yuen, Chau Ming So
Summary: This study presents a new palladium-catalyzed reaction for synthesizing unsymmetrical biaryl compounds containing triflate moiety. The reaction shows high reactivity and chemoselectivity, and can be scaled up without diminishing the yield and selectivity.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Review
Chemistry, Multidisciplinary
Susumu Oda, Takuji Hatakeyama
Summary: This study demonstrates efficient borylation reactions of arenes toward organoboron-based materials, resulting in the construction of polycyclic frameworks with ring-junction boron atoms. Electron-rich arenes can undergo one-shot multiple borylations, leading to compounds with attractive optoelectronic properties and substantial stabilities. These reactions are efficient, easy to scale up, and do not require precious reagents, paving the way for the development of next-generation optoelectronic materials.
BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN
(2021)
Article
Chemistry, Multidisciplinary
Shu Sakamoto, Trevor W. Butcher, Jonathan L. Yang, John F. Hartwig
Summary: This study demonstrates a palladium-catalyzed gem-difluoroallylation reaction of aryl and pseudo halides with 3,3-difluoroallyl boronates in high yield and regioselectivity. The reactants are prepared using a copper-catalyzed synthesis method, and the reaction can tolerate a wide range of functional groups, providing a versatile synthesis for valuable intermediates in the preparation of fluorinated building blocks.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Applied
A. Ahmed Raza, Seenu Ravi, S. Syed Tajudeen, A. K. Ibrahim Sheriff
Summary: The trifunctional covalent triazine and carbonyl-based polymer with acid-base and metal active sites (CTCP-SO3HEDA/Pd) was synthesized through a multistep Friedel-Crafts reaction, post-synthetic sulfonation, Schiff base condensation, and metal nanoparticle incorporation. CTCP-SO3HEDA/Pd was evaluated as a heterogeneous catalyst for a one-pot reaction, showing high selectivity and good yield of the desired product. The catalyst could be easily recovered and reused with minor loss of activity and selectivity for five runs.
REACTIVE & FUNCTIONAL POLYMERS
(2021)
Article
Chemistry, Multidisciplinary
Koki Kise, Shota Ooi, Hayate Saito, Hideki Yorimitsu, Atsuhiro Osuka, Takayuki Tanaka
Summary: Peripherally pi-extended corannulenes with quintuple azahelicene units were prepared and their dynamic behaviors were studied. Analysis revealed that the structural isomers can interchange in solution, depending on steric congestion, and the co-existing moieties influence the conformational dynamics, reducing activation energy barriers for isomerization.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Qian Zhang, Shijun Deng, Dong Li, Jun Shimokawa, Hideki Yorimitsu
Summary: A facile and efficient AgF-mediated electrophilic amination of alkoxyarylsilanes with azodicarboxylates has been developed. The reaction proceeds under green and mild conditions, generating aryl hydrazines.
CHEMISTRY-AN ASIAN JOURNAL
(2022)
Article
Biochemistry & Molecular Biology
Kazuhira Miwa, Shinobu Aoyagi, Takahiro Sasamori, Shogo Morisako, Hiroshi Ueno, Yutaka Matsuo, Hideki Yorimitsu
Summary: The reduction of fullerene (C-60) with sodium dispersion in the presence of an excess amount of dipropyl sulfate yields highly propylated fullerene, C-60(nC(3)H(7))(n) (max. n = 24), with C-60(nC(3)H(7))(20) being predominantly generated as indicated by mass spectrometry.
Article
Chemistry, Organic
Shuo Wang, Atsushi Kaga, Takashi Kurogi, Hideki Yorimitsu
Summary: In this study, treatment of arylcyclopropanecarboxamides with a sodium dispersion in the presence of methoxypinacolborane as a reduction-resistant electrophile was investigated. The results showed that the reaction led to the reductive cleavage of the cyclopropane ring followed by instant trapping with the boron electrophile, resulting in the formation of enolates of gamma-aryl-gamma-borylalkanamides. The enolates could further react with a different electrophile to produce the corresponding a-substituted amides with anti selectivity.
Article
Chemistry, Organic
Shunsuke Koyama, Fumiya Takahashi, Hayate Saito, Hideki Yorimitsu
Summary: Treatment of alkenyl carbamates with sodium dispersion and a co-existing boron electrophile leads to the formation of alkenylboronates through the reductive cleavage of the vinylic C-O bond, facilitated by the instant trapping of reactive organosodium species.
SYNTHESIS-STUTTGART
(2023)
Article
Chemistry, Organic
Hiroki Yamagishi, Fuyuki Harata, Jun Shimokawa, Hideki Yorimitsu
Summary: In this study, we introduce sodium diphenylsilylsilanolates as new stable and convenient silylating reagents, which can be synthesized from chlorosilanes. The new reagents exhibit the ability to deliver various silyl groups in palladium-catalyzed silylation of aryl bromides, regardless of the steric and electronic properties of the silyl groups to be transferred.
Article
Chemistry, Multidisciplinary
Shuo Wang, Igor Larrosa, Hideki Yorimitsu, Gregory J. P. Perry
Summary: The potassium salts of carboxylic acids are developed as efficient carboxylating agents through CO2 exchange. These carboxylates function as a combined source of CO2 and base/metalating agent, making them dual-function reagents. By using the salt of a commercially available carboxylic acid, this protocol provides a convenient and practical alternative to using CO2 gas or organometallic reagents, without the need for pressurized containers or strictly inert conditions. The reaction is mild, transition metal-free, and exhibits a wide range of substrate compatibility. The strategy showcased the ability to isotopically label biologically important molecules using low amounts of labeled CO2.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Fumiya Takahashi, Hideki Yorimitsu
Summary: In this study, regio- and stereoselective synthesis of Tetraarylethylenes (TAEs) was achieved through sodium-promoted reductive anti-1,2-dimagnesiation of alkynes and palladium-catalyzed arylation. This method not only enables the synthesis of diarylacetylenes, but also allows for the synthesis of alkyl aryl acetylenes, expanding the range of possible TAEs.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Kazuhira Miwa, Shinobu Aoyagi, Toru Amaya, Takahiro Sasamori, Shogo Morisako, Takashi Kurogi, Hideki Yorimitsu
Summary: The curved and π-conjugated surface of bowl-shaped corannulene has been multiply methylated through in-situ iterative reduction/methylation sequences, resulting in exo-di-, -tetra-, and -hexamethylated corannulenes. Various analytical techniques have been used to reveal the molecular structures of the multimethylated corannulenes and the sequence of the multimethylation. This work has the potential to contribute to the controlled synthesis and characterization of multifunctionalized fullerenes.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Tomohiko Sato, Somnath N. Karad, Jun Shimokawa, Hideki Yorimitsu
Summary: The regioselective anti-silyllithiation of propargylic amines provides an efficient route for the synthesis of alkenylsilanes. The reaction involves the formation of a stable alkenyllithium intermediate through intramolecular coordination of the nitrogen functional group. After treatment with an electrophile, the alkenyllithium intermediate is functionalized to yield tetrasubstituted allylic amines bearing a beta-silicon substituent.
Article
Chemistry, Physical
Hiroki Yamagishi, Jun Shimokawa, Hideki Yorimitsu
Summary: The multifaceted implementation of silanols in organic synthesis is reviewed in terms of advances in transition metal-catalyzed reactions. The major properties of silanols are summarized, including their use as nucleophiles to serve as bulky surrogates for water, as temporary ligands to control the regioselectivity of metal-catalyzed reactions, and as coupling partners for transferring functional groups. These summaries provide opportunities for future developments in silanol chemistry.
Article
Chemistry, Organic
Ziwei Zhang, Fumiya Takahashi, Takashi Kurogi, Hideki Yorimitsu
Summary: The preparation of vinylic lithium reagents from vinylic halides is common in organic synthesis, but not always easy. This study proposes a new method using silyl enolates of alkyl aryl ketones, which provides readily available and efficient vinylic lithium species. The reductive transformation of electron-rich silyl enolates has significant potential for various applications in organic synthesis, serving as an alternative to the Shapiro reaction.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Sara Suzuki, Soni Aman Govind, Kosuke Imamura, Hideki Yorimitsu, Hiroshi Shinokubo, Masahiro Higashi, Hirofumi Sato
Summary: The radical cyclization reaction in aqueous environment by Yorimitsu et al. was reexamined using the RISM-SCF-cSED method, a hybrid approach combining quantum chemistry and statistical mechanics for molecular liquids. The difference in barrier height between the forward reaction from the intermediate E-rot, the cyclization step, and the backward reaction is crucial for the reaction yield. By considering the effect of hydrogen bonding through the RISM theory, it was found that the barrier height for the forward reaction is lower, particularly in water. In other words, accounting for microscopic solvation effects clearly elucidates the disparity between water and DMSO solvents, explaining the significant acceleration of the reaction in the aqueous environment.
CHEMICAL PHYSICS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Yiyuan Jiang, Hideki Yorimitsu
Summary: This study demonstrates the efficient generation of 1,4-organodilithiums through the reduction of styrenes with lithium arenide in flow microreactors. The use of a flow reactor with fast mixing is essential for achieving high efficiency and selectivity, which are low under batch conditions. The resulting 1,4-organodilithiums can react with various electrophiles to yield precursors for useful yet less accessible cyclic structures.
Article
Chemistry, Multidisciplinary
Hiroki Yamagishi, Kenshiro Hitoshio, Jun Shimokawa, Hideki Yorimitsu
Summary: This study extends the utility of sodium silylsilanolates as competent precursors of silylcoppers, and the mechanistic studies through DFT calculation reveal the mechanism of copper silylsilanolate transforming into silylcopper.
