Papers - YASUKAWA Naoki
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Chiral Phosphoric Acid-Catalyzed Enantioselective Synthesis of 2,2-Disubstituted 2,3-Dihydro-4-quinolones from Isatins and 2′-Aminoacetophenones
Hidenori Andatsu, Yuto Terashima, Rio Kawamura, Yoichiro Matsuda, Tsunayoshi Takehara, Takeyuki Suzuki, Naoki Yasukawa, Shuichi Nakamura
Organic Letters 2025.01
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Photocatalytic Strategy for Decyanative Transformations Enabled by Amine-Ligated Boryl Radical
Yuto Yoshida, Waka Okada, Kazutake Takada, Shuichi Nakamura, Naoki Yasukawa
Organic Letters 2025.01
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Amine-Ligated Boryl Radical-Enabled Hydrofunctionalization of Styrenes via Halogen-Atom Transfer of Alkyl and Aryl Bromides Invited Reviewed
Naoki Yasukawa,* Seiya Naito, Koki Obata, Shuichi Nakamura*
Synthesis 2024.10
Authorship：Lead author, Corresponding author Language：English Publishing type：Research paper (scientific journal)
DOI： 10.1055/a-2427-9313
Other Link： https://www.thieme-connect.com/products/ejournals/abstract/10.1055/a-2427-9313
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Asymmetric Conjugate Addition of Phosphine Sulfides to α-Substituted β-Nitroacrylates Using Cinchona Alkaloid Amide Catalysts Reviewed
Kosei Miyake, Akane Iwamura, Kazuki Fujita, Tsunayoshi Takehara, Takeyuki Suzuki, Naoki Yasukawa, Shuichi Nakamura
Organic Letters 26 ( 39 ) 8233 - 8238 2024.09
Language：English Publishing type：Research paper (scientific journal)
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Synthesis and Suzuki–Miyaura Cross-Coupling of Alkyl Amine-Boranes. A Boryl Radical-Enabled Strategy Reviewed International coauthorship
Cornelia S. Buettner, Chiara Stavagna, Michael J. Tilby, Bartosz Górski, James J. Douglas, Naoki Yasukawa, Daniele Leonori
Journal of the American Chemical Society 146 ( 34 ) 24042 - 24052 2024.08
Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal)
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Organocatalytic Stereoselective Decarboxylative Addition of α-Amido Malonic Acid Half Oxyesters to Isatins Reviewed
Kazuki Fujita, Ibuki Kumazawa, Jyunpei Yokoi, Kazuki Abe, Tsunayoshi Takehara, Takeyuki Suzuki, Naoki Yasukawa, Shuichi Nakamura*
Advanced Synthesis & Catalysis 366 ( 3 ) 438 - 443 2024.02
Language：English Publishing type：Research paper (scientific journal)
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Direct Regioselective Dehydrogenation of α‐Substituted Cyclic Ketones Reviewed
Sebastian Armin Schwengers, Gabriela Guillermina Gerosa, Tynchtyk Amatov, Naoki Yasukawa, Sebastian Brunen, Markus Leutzsch, Benjamin Mitschke, Grigory Shevchenko, Benjamin List
Angewandte Chemie International Edition 2023.06
Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley
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Asymmetric synthesis of tetrasubstituted cyclic amines via aza-Henry reaction using cinchona alkaloid sulfonamide/zinc(ii) catalysts Reviewed
Naoki Yasukawa, Ami Yamanoue, Tsunayoshi Takehara, Takeyuki Suzuki, Shuichi Nakamura
Chemical Communications 2021.12
Authorship：Lead author, Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Royal Society of Chemistry ({RSC})
DOI： 10.1039/D1CC06492D
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Gold-Catalyzed Tandem Oxidative Coupling Reaction between β-Ketoallenes and Electron-Rich Arenes to 2-Furylmethylarenes
Naoki Yasukawa, Yutaro Yamada, Chikara Furugen, Yuya Miki, Hironao Sajiki, Yoshinari Sawama
Organic Letters 23 ( 15 ) 5891 - 5895 2021.07
Authorship：Lead author, Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society ({ACS})
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Palladium on Carbon–Catalyzed Oxidative Transformation of Benzylic Ethers
Ryoya Takakura, Shoko Kuwata, Kouki Nakano, Naoki Yasukawa, Hironao Sajiki, Yoshinari Sawama
HETEROCYCLES 103 ( 1 ) 494 - 494 2021
Publishing type：Research paper (scientific journal) Publisher：The Japan Institute of Heterocyclic Chemistry
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Copper‐Catalyzed Aqueous N−O Bond Cleavage of 2‐Oxa‐3‐Azabicyclo Compounds to Cyclic cis ‐1,4‐Amino Alcohols
Naoki Yasukawa, Yuya Miki, Marina Kuwata, Hironao Sajiki, Yoshinari Sawama
ChemSusChem 13 ( 21 ) 5632 - 5637 2020.11
Authorship：Lead author Publishing type：Research paper (scientific journal) Publisher：Wiley
© 2020 Wiley-VCH GmbH The N−O bond cleavage of 2-oxa-3-azabicyclo substrates, which are readily prepared by the hetero Diels-Alder reaction between nitroso dienophiles and cyclic 1,3-dienes, was effectively catalyzed by heterogeneous copper-on-carbon (Cu/C) under aqueous conditions to give the corresponding cyclic cis-1,4-amino alcohol derivatives. The present method was applied to the direct incorporation of the hydroxy and amino groups derived from a nitroso substrate into cyclic 1,3-dienes with cis-selectivity by the combination of the in situ formation of 2-oxa-3-azabicyclo compounds and following Cu/C-catalyzed N−O bond cleavage. The obtained cis-4-aminocyclohexenols, derived from cyclohexadiene as a cyclic 1,3-diene, could be selectively oxidized by using the ruthenium-on-carbon (Ru/C) catalyst under oxygen atmosphere to the corresponding 4-aminocyclohexenones at 50–65 °C or para-iminoquinones at 100–110 °C as useful reactive synthetic precursors.
Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/cssc.202001739
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Platinum on Carbon–Catalyzed and Chemoselective Aqueous Oxygen Oxidation of Aromatic Acetals to Benzoic Acids
Naoki Yasukawa, Takumi Matsuda, Eisho Shimizu, Hironao Sajiki, Yoshinari Sawama
HETEROCYCLES 100 ( 1 ) 145 - 145 2020
Authorship：Lead author Language：English Publishing type：Research paper (scientific journal) Publisher：Japan Institute of Heterocyclic Chemistry
Novel chemoselective transformations can diversify the synthetic pathways of the target molecules. The chemoselective oxidation of aromatic acetals to benzoic acid derivatives under platinum on carbon (Pt/C)-catalyzed oxygen oxidation conditions has been newly developed with a tolerance of aliphatic acetals and ketals. The present oxidation was clean and useful from the viewpoint of the easy removal of Pt/C and the use of molecular oxygen as a green oxidant in water as an abundant, non-toxic and environmentally friendly solvent.
DOI： 10.3987/com-19-14122
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Birch-Type Reduction of Arenes in 2-Propanol Catalyzed by Zero-Valent Iron and Platinum on Carbon
Yoshinari Sawama, Kazuho Ban, Kazuhiro Akutsu-Suyama, Hiroki Nakata, Misato Mori, Tsuyoshi Yamada, Takahiro Kawajiri, Naoki Yasukawa, Kwihwan Park, Yasunari Monguchi, Yukio Takagi, Masatoshi Yoshimura, Hironao Sajiki
ACS Omega 4 ( 7 ) 11522 - 11531 2019.07
Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society ({ACS})
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Synthesis of Pyrroles from 3,6-Dihydro-2H-1,2-oxazines on Cu/C
Yasukawa Naoki
Synfacts 15 ( 01 ) 0074 - 0074 2019.01
Language：English Publishing type：Research paper (scientific journal) Publisher：Georg Thieme Verlag {KG}
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Stainless Steel-Mediated Hydrogen Generation from Alkanes and Diethyl Ether and Its Application for Arene Reduction
Yoshinari Sawama, Naoki Yasukawa, Kazuho Ban, Ryota Goto, Miki Niikawa, Yasunari Monguchi, Miki Itoh, Hironao Sajiki
Organic Letters 20 ( 10 ) 2892 - 2896 2018.05
Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS)
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Highly-functionalized arene synthesis based on palladium on carbon-catalyzed aqueous dehydrogenation of cyclohexadienes and cyclohexenes
Naoki Yasukawa, Hiroki Yokoyama, Masahiro Masuda, Yasunari Monguchi, Hironao Sajiki, Yoshinari Sawama
Green Chemistry 20 ( 6 ) 1213 - 1217 2018
Authorship：Lead author Language：English Publishing type：Research paper (scientific journal) Publisher：Royal Society of Chemistry (RSC)
<p>Highly-functionalized arenes could be efficiently constructed by Pd/C-catalyzed aqueous dehydrogenation of 1,4-cyclohexadienes and cyclohexenes.</p>
DOI： 10.1039/c7gc03819d
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Copper-catalyzed pyrrole synthesis from 3,6-dihydro-1,2-oxazines
Naoki Yasukawa, Marina Kuwata, Takuya Imai, Yasunari Monguchi, Hironao Sajiki, Yoshinari Sawama
Green Chemistry 20 ( 19 ) 4409 - 4413 2018
Authorship：Lead author Language：English Publishing type：Research paper (scientific journal) Publisher：Royal Society of Chemistry (RSC)
<p>The highly-functionalized pyrroles could be efficiently synthesized from 3,6-dihydro-1,2-oxazines using only heterogeneous Cu/C under neat heating conditions.</p>
DOI： 10.1039/c8gc01373j
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Palladium on Carbon-Catalyzed Benzylic Methoxylation for Synthesis of Mixed Acetals and Orthoesters
Naoki Yasukawa, Takafumi Kanie, Marina Kuwata, Yasunari Monguchi, Hironao Sajiki, Yoshinari Sawama
Chemistry - A European Journal 23 ( 46 ) 10974 - 10977 2017.08
Authorship：Lead author Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley
The palladium on carbon (Pd/C)-catalyzed direct methoxylation of the benzylic positions of linear benzyl and cyclic ether substrates proceeded in the presence of i-Pr2NEt under an oxygen atmosphere to give the corresponding mixed acetals. Cyclic acetal derivatives could also be converted into orthoesters. The present direct methoxylation via a carbon-hydrogen (C-H) functionalization can be accomplished using the easily-removed Pd/C and molecular oxygen as a green oxidant. The obtained mixed acetals were transformed into the corresponding ether products by chemoselective substitution of the methoxy group using a silyltriflate, 2,4,6-collidine, and a nucleophile. The orthoester derivative could also be transformed into the cyclic ketal under similar reaction conditions.
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Palladium on Carbon-Catalyzed Chemoselective Oxygen Oxidation of Aromatic Acetals International journal
Naoki Yasukawa, Shota Asai, Maho Kato, Yasunari Monguchi, Hironao Sajiki, Yoshinari Sawama
Organic Letters 18 ( 21 ) 5604 - 5607 2016.11
Authorship：Lead author Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society (ACS)
The development of an unprecedented chemoselective transformation has contributed to forming a novel synthetic process for target molecules. Chemoselective oxidation of aromatic acetals has been accomplished using a reusable palladium on carbon catalyst under atmospheric oxygen conditions to form ester derivatives with tolerance of aliphatic acetals and ketals.
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Mild and Direct Multiple Deuterium-Labeling of Saturated Fatty Acids
Tsuyoshi Yamada, Kwihwan Park, Naoki Yasukawa, Kosuke Morita, Yasunari Monguchi, Yoshinari Sawama, Hironao Sajiki
Advanced Synthesis & Catalysis 358 ( 20 ) 3277 - 3282 2016.08
Publishing type：Research paper (scientific journal) Publisher：Wiley-Blackwell
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Disiloxane Synthesis Based on Silicon–Hydrogen Bond Activation using Gold and Platinum on Carbon in Water or Heavy Water International journal
Yoshinari Sawama, Masahiro Masuda, Naoki Yasukawa, Ryosuke Nakatani, Shumma Nishimura, Kyoshiro Shibata, Tsuyoshi Yamada, Yasunari Monguchi, Hiroyasu Suzuka, Yukio Takagi, Hironao Sajiki
The Journal of Organic Chemistry 81 ( 10 ) 4190 - 4195 2016.05
Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society ({ACS})
Disiloxanes possessing a silicon-oxygen linkage are important as frameworks for functional materials and coupling partners for Hiyama-type cross coupling. We found that disiloxanes were effectively constructed of hydrosilanes catalyzed by gold on carbon in water as the solvent and oxidant in association with the emission of hydrogen gas at room temperature. The present oxidation could proceed via various reaction pathways, such as the hydration of hydrosilane into silanol, dehydrogenative coupling of hydrosilane into disilane, and the subsequent corresponding reactions to disiloxane. Additionally, the platinum on carbon catalyzed hydrogen-deuterium exchange reaction of arylhydrosilanes as substrates in heavy water proceeded on the aromatic nuclei at 80 °C with high deuterium efficiency and high regioselectivity at the only meta and para positions of the aromatic-silicon bond to give the deuterium-labeled disiloxanes.
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Additional Nucleophile-Free FeCl<sub>3</sub>-Catalyzed Green Deprotection of 2,4-Dimethoxyphenylmethyl-Protected Alcohols and Carboxylic Acids
Yoshinari Sawama, Masahiro Masuda, Akie Honda, Hiroki Yokoyama, Kwihwan Park, Naoki Yasukawa, Yasunari Monguchi, Hironao Sajiki
Chemical and Pharmaceutical Bulletin 64 ( 7 ) 778 - 784 2016
Language：English Publishing type：Research paper (scientific journal) Publisher：Pharmaceutical Society of Japan
The deprotection of the methoxyphenylmethyl (MPM) ether and ester derivatives can be generally achieved by the combinatorial use of a catalytic Lewis acid and stoichiometric nucleophile. The deprotections of 2,4-dimethoxyphenylmethyl (DMPM)-protected alcohols and carboxylic acids were found to be effectively catalyzed by iron(III) chloride without any additional nucleophile to form the deprotected mother alcohols and carboxylic acids in excellent yields. Since the present deprotection proceeds via the self-assembling mechanism of the 2,4-DMPM protective group itself to give the hardly-soluble resorcinarene derivative as a precipitate, the rigorous purification process by silica-gel column chromatography was unnecessary and the sufficiently-pure alcohols and carboxylic acids were easily obtained in satisfactory yields after simple filtration.
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Biarylmethane and Fused Heterocyclic Arene Synthesis via in Situ Generated o- and/or p-Naphthoquinone Methides International journal
Yoshinari Sawama, Takahiro Kawajiri, Shota Asai, Naoki Yasukawa, Yuko Shishido, Yasunari Monguchi, Hironao Sajiki
The Journal of Organic Chemistry 80 ( 11 ) 5556 - 5565 2015.05
Language：English Publishing type：Research paper (scientific journal) Publisher：American Chemical Society ({ACS})
o- and/or p-naphthoquinone methides (NQMs) can be selectively prepared by the ring opening of 1-(siloxymethyl)-1,4-epoxy-1,4-dihydronaphthalene derivatives based on a substituent effect at the 4 position of the substrates. The 4-alkyl- or silyl-substituted 1-(siloxymethyl)-1,4-epoxy-1,4-dihydronaphthalene was transformed to o-NQM (1-naphthoquinone-2-methide), which underwent Friedel-Crafts 1,4-addition of the α,β-unsaturated carbonyl moiety to provide the 2-benzyl-1-naphthol as the biarylmethane and [4 + 2]-cycloaddition with a dienophile to give the fused heterocyclic arene. Meanwhile, the 4-unsubstituted 1-(siloxymethyl)-1,4-epoxy-1,4-dihydronaphthalene could be converted to the corresponding 4-benzyl-1-naphthol by the Friedel-Crafts 1,6-addition of p-NQM (1-naphthoquinone-4-methide) generated by the site-selective ring opening of the 1,4-epoxy moiety. Furthermore, the 4-(siloxymethyl)-(1,4-bis(siloxymethyl))-1,4-epoxy-1,4-dihydronaphthalene was transformed into a 2,4-bisbenzyl-1-naphthol or pentacyclic derivative via both the o- and p-NQM intermediates.
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