{"id":138,"date":"2024-03-05T14:04:51","date_gmt":"2024-03-05T05:04:51","guid":{"rendered":"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/?page_id=138"},"modified":"2024-06-27T15:14:01","modified_gmt":"2024-06-27T06:14:01","slug":"research-2","status":"publish","type":"page","link":"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/en\/research-2\/","title":{"rendered":"Research"},"content":{"rendered":"<p><span style=\"font-family: helvetica, arial, sans-serif;\">We are developing new chemical reactions by integrating different fields such as chemistry, pharmacology, medicine, and agriculture, using photochemistry as a key. For example, we are investigating chemical reactions to convert dairy-derived biogas into liquid energy such as methanol and formic acid through the photochemistry of chlorine dioxide, and we are researching new therapeutic agents using catalysts that absorb specific light.<\/span><\/p>\n<h2 id=\"1\"><strong><span style=\"font-family: helvetica, arial, sans-serif;\">Development of chemical reactions using chlorine dioxide<\/span><\/strong><\/h2>\n<h3><span style=\"font-family: helvetica, arial, sans-serif;\">Methanol synthesis from biogas<\/span><\/h3>\n<div align=\"center\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-05-01-12.59.46.png\" alt=\"\" width=\"1177\" height=\"520\" class=\"alignnone size-full wp-image-834\" srcset=\"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-05-01-12.59.46.png 1177w, https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-05-01-12.59.46-300x133.png 300w, https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-05-01-12.59.46-1024x452.png 1024w, https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-05-01-12.59.46-768x339.png 768w\" sizes=\"auto, (max-width: 1177px) 100vw, 1177px\" \/>Ohkubo, K.; Hirose, K. Angew. <i>Chem. Int. Ed.<\/i> 2018, 57, 2126<\/div>\n<div align=\"center\"><\/div>\n<h3><span style=\"font-family: helvetica, arial, sans-serif;\">Chemical conversion of biogas into useful substances<\/span><\/h3>\n<p class=\"big_red\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-05-01-13.00.03.png\" alt=\"\" width=\"1452\" height=\"904\" class=\"alignnone size-full wp-image-833\" srcset=\"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-05-01-13.00.03.png 1452w, https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-05-01-13.00.03-300x187.png 300w, https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-05-01-13.00.03-1024x638.png 1024w, https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-05-01-13.00.03-768x478.png 768w\" sizes=\"auto, (max-width: 1452px) 100vw, 1452px\" \/><\/p>\n<div align=\"center\"><\/div>\n<h3><span style=\"font-family: helvetica, arial, sans-serif;\">Carbon-neutral circular dairy farming<\/span><\/h3>\n<div align=\"center\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-04-30-18.32.06-1.png\" alt=\"\" width=\"906\" height=\"598\" class=\"alignnone wp-image-830 size-full\" srcset=\"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-04-30-18.32.06-1.png 906w, https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-04-30-18.32.06-1-300x198.png 300w, https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-04-30-18.32.06-1-768x507.png 768w\" sizes=\"auto, (max-width: 906px) 100vw, 906px\" \/><\/div>\n<div align=\"center\"><iframe loading=\"lazy\" width=\"560\" height=\"314\" src=\"\/\/www.youtube.com\/embed\/Cmz9l1gsCYA?si=s71d66pGPwBVofr3\" allowfullscreen=\"allowfullscreen\"><\/iframe><\/div>\n<div align=\"center\"><\/div>\n<h2 id=\"2\">Organic photoredox catalysts and chemical reactions<\/h2>\n<div><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/04\/Pasted-Graphic.jpg\" alt=\"\" width=\"848\" height=\"420\" class=\"alignnone size-full wp-image-807\" srcset=\"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/04\/Pasted-Graphic.jpg 848w, https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/04\/Pasted-Graphic-300x149.jpg 300w, https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/04\/Pasted-Graphic-768x380.jpg 768w\" sizes=\"auto, (max-width: 848px) 100vw, 848px\" \/><\/div>\n<div><span lang=\"EN-GB\" style=\"font-family: helvetica, arial, sans-serif;\">A variety of novel organic synthetic transformations have been made possible by organic photoredox catalysis via photoinduced electron-transfer reactions. <\/span><\/div>\n<div><span lang=\"EN-US\" style=\"font-family: helvetica, arial, sans-serif;\">As described above, photocatalytic reactions are made possible by using the electron-transfer state of Acr<sup>+<\/sup>\u2013Mes, which can oxidize and reduce external electron donors and acceptors to produce the radical cations and radical anions, respectively. The reactions of radical cations with superoxide anion (O<sub>2<\/sub><sup>\u2022\u2013<\/sup>) can efficiently compete with the back electron transfer to yield the oxygenated products. Substrates that cannot react with singlet oxygen can be readily oxygenated by oxygen with Acr<sup>+<\/sup>\u2013Mes under visible light irradiation. The oxygenated products become much more difficult to be oxidized by the electron-transfer state of Acr<sup>+<\/sup>\u2013Mes, when the selective photocatalytic oxygenation of substrates, which would otherwise be very difficult to achieve, has been made possible with Acr<sup>+<\/sup>\u2013Mes. The reactions of radical cations produced by electron transfer from electron donor substrates to the electron-transfer state of Acr<sup>+<\/sup>\u2013Mes with nucleophiles such as Br<sup>\u2013<\/sup> can also afford the adducts with nucleophiles, when the electron-transfer oxidation of substrates with the electron-transfer state of Acr<sup>+<\/sup>\u2013Mes is much faster than that of nucleophiles. In addition, the radical coupling of neutral radicals produced by deprotonation of the produced radical cations can be utilized for the C-C bond formation reactions. Thus, photocatalytic reactions of Acr<sup>+<\/sup>\u2013Mes under visible light irradiation provide new ways to design environmentally benign synthesis. <\/span><\/div>\n<div><span lang=\"EN-GB\" style=\"font-family: helvetica, arial, sans-serif;\">In particular, the use of the excited states of 2,3-dichloro-5,6-dicyano-<i>p<\/i>-benzoquinone (DDQ) and 3-cyano-1-methylquinolinium ion (QuCN<sup>+<\/sup>), which have strong oxidizing ability has made it possible to oxygenate benzene to phenol via formation of benzene radical cation.<\/span><\/div>\n<h2 id=\"3\"><span style=\"font-family: helvetica, arial, sans-serif;\">Lithium-ion-encapsulated fullerene<\/span>\uff08Li+@C<sub>60<\/sub>\uff09<\/h2>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-05-01-10.57.53.png\" alt=\"\" width=\"777\" height=\"775\" class=\"alignnone size-full wp-image-810\" srcset=\"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-05-01-10.57.53.png 777w, https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-05-01-10.57.53-300x300.png 300w, https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-05-01-10.57.53-150x150.png 150w, https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-content\/uploads\/2024\/05\/\u30b9\u30af\u30ea\u30fc\u30f3\u30b7\u30e7\u30c3\u30c8-2024-05-01-10.57.53-768x766.png 768w\" sizes=\"auto, (max-width: 777px) 100vw, 777px\" \/><\/p>\n<p><span style=\"font-family: helvetica, arial, sans-serif;\">Lithium-ion-encapsulated fullerene (Li+@C60) exhibits greatly enhanced reactivity in photoinduced electrontransfer reduction with electron donors compared with pristine C60. The enhanced reactivity of Li+@C60 results from the more positive one-electron reduction potential of Li+@C60 (+0.14 V versus a standard calomel electrode (SCE)) than that of C60 (\u20020.43 V versus SCE), whereas the reorganization energy of electron transfer of Li+@C60 (1.01 eV) becomes larger than that of C60 (0.73 eV) because of the change in electrostatic interactions of encapsulated Li+ upon electron transfer. Li+@C60 can form strong supramolecular complexes with various anionic electron donors through electrostatic interactions. Li+@C60 can also form strong supramolecular p complexes with various electron donors, such as cyclic porphyrin dimers, corannulene, and crown ether fused monopyrrolotetrathiafulvalenes. Photoinduced electron transfer from electron donors to Li+@C60 afforded long-lived chargeseparated states of supramolecular complexes between electron donors and Li+@C60. A photoelectrochemical solar cell composed of supramolecular nanoclusters of Li+@C60 and zinc sulfonated meso-tetraphenylporphyrin exhibits significant enhancement in the photoelectrochemical performance than that of the reference system containing only a single component.<\/span><\/p>\n","protected":false},"excerpt":{"rendered":"<h2>Research<\/h2>\n<ul>\n<li><a href=\"#1\">\u30d0\u30a4\u30aa\u30ac\u30b9\u304b\u3089\u30e1\u30bf\u30ce\u30fc\u30eb\u5408\u6210<\/a><\/li>\n<li><a href=\"#2\">\u30d0\u30a4\u30aa\u30ac\u30b9\u3092\u6709\u7528\u7269\u8cea\u3078\u5316\u5b66\u5909\u63db<\/a><\/li>\n<li><a href=\"#3\">\u30ab\u30fc\u30dc\u30f3\u30cb\u30e5\u30fc\u30c8\u30e9\u30eb\u5faa\u74b0\u578b\u916a\u8fb2<\/a><\/li>\n<\/ul>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-138","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-json\/wp\/v2\/pages\/138","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-json\/wp\/v2\/comments?post=138"}],"version-history":[{"count":9,"href":"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-json\/wp\/v2\/pages\/138\/revisions"}],"predecessor-version":[{"id":881,"href":"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-json\/wp\/v2\/pages\/138\/revisions\/881"}],"wp:attachment":[{"href":"https:\/\/www.irdd.osaka-u.ac.jp\/ohkubo\/wp-json\/wp\/v2\/media?parent=138"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}