研究者詳細 - ウヤヌク　ムハメット

論文 - ウヤヌク　ムハメット

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ウヤヌクムハメット, 石原一彰

TCIメール 2019 巻 ( 182 ) 頁： 2 - 16 2019年12月

担当区分：責任著者記述言語：日本語掲載種別：研究論文（学術雑誌）

環境・エネルギー・資源問題が深刻化するなか，物質文明社会の持続的発展のためには，環境低負荷型触媒的精密有機合成法の開拓が有機合成化学の最重要課題の一つであり，遷移金属等のレアメタルや重金属等の毒性の強い金属資源を反応剤や触媒に用いる従来型の有機合成化学からの脱却が求められている。これに関連し近年，有毒な重金属酸化物の代替物質として超原子価ヨウ素化合物が注目されている。しかし，超原子価ヨウ素の化学は1世紀以上の長い歴史をもつにもかかわらず，不斉酸化反応の成功例はほとんどなく，不斉有機触媒の最も挑戦的な課題の一つとされていた。我々は，それまでの触媒設計概念とは全く異なる配座柔軟性に富むキラルヨードアレーンを分子設計した。本設計は，触媒活性中心（I(III)）と側鎖末端の間に適切な非共有結合性二次的相互作用を導入することで有効な不斉場を構築することを特徴とし，酵素反応に見られる誘導適合のような不斉誘導が可能となる。これらの柔軟かつ機能的な触媒は，様々な酸化的変換反応において世界中で利用されるようになってきている。本総説では我々のC 2対称ジアミド型触媒設計とその応用例について紹介する。

High-Performance Ammonium Hypoiodite/Oxone Catalysis for Enantioselective Oxidative Dearomatization of Arenols 査読有り

Muhammet Uyanik, Takehiro Kato, Naoto Sahara, Outa Katade, Kazuaki Ishihara

ACS Catalysis 9 巻 ( 12 ) 頁： 11619 - 11626 2019年11月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

A high-performance enantioselective quaternary ammonium hypoiodite catalysis was developed for the dearomatization of arenols using oxone as an environmentally benign oxidant. The oxidation of not only 1- and 2-naphthols but also phenols, which were hardly reactive using the previous hypoiodite catalysis, readily proceeded under mild conditions, and only inorganic wastes were generated from the oxidant used. Control experiments and Raman analysis revealed the in situ generation of I+ such as hypoiodous acid as an unstable active species and molecular iodine (I2) as a stable dormant species. Most of the advantages of the present I+/oxone catalysis, compared to previous I+/(H2O2 or ROOH) systems, may result from generation of the stable dormant state and the higher reactivity of catalysts under acidic conditions.

DOI： 10.1021/acscatal.9b04322

Ammonium Hypoiodite-Catalyzed Oxidative Dearomatizative Azidation of Arenols 査読有り

Muhammet Uyanik, Kohei Nishioka, Kazuaki Ishihara

Chemistry Letters 48 巻 ( 4 ) 頁： 353 - 356 2019年1月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

The first transition metal-free catalytic oxidative dearomatizative azidation of arenols has been developed using hypoiodite catalysis with aqueous hydrogen peroxide and trimethylsilyl azide as an oxidant and azide source, respectively, under mild conditions. The corresponding quaternary azides can be obtained in high to excellent yields.

DOI： 10.1246/cl.181036

Front Cover: Regioselective Oxidative Chlorination of Arenols Using NaCl and Oxone (Eur. J. Org. Chem. 1/2019) 査読有り

Muhammet Uyanik, Naoto Sahara, Kazuaki Ishihara

European Journal of Organic Chemistry 2019 巻 ( 1 ) 頁： 1 - 1 2019年1月

Regioselective Oxidative Chlorination of Arenols Using NaCl and Oxone 招待有り査読有り

Muhammet Uyanik, Naoto Sahara, Kazuaki Ishihara

European Journal of Organic Chemistry 2019 巻 ( 1 ) 頁： 27 - 31 2018年10月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

We developed a practical and environmentally benign method for the chlorinative dearomatization of arenols using transient electrophilic chlorinating species generated in situ from inexpensive sodium chloride and Oxone as a Cl source and oxidant, respectively, under mild conditions. Moreover, the regioselective chlorination or chlorinative dearomatization of 1-naphthols was also achieved by changing the reaction conditions.

DOI： 10.1002/ejoc.201801063

Asymmetric Total Synthesis of (-)-Maldoxin, a Common Biosynthetic Ancestor of the Chloropupukeananin Family 査読有り

Takahiro Suzuki, Soichiro Watanabe, Muhammet Uyanik, Kazuaki Ishihara, Susumu Kobayashi, Keiji Tanino

Organic Letters 20 巻 ( 20 ) 頁： 3919 - 3922 2018年6月

記述言語：英語掲載種別：研究論文（学術雑誌）

The total synthesis of pestheic acid based on an intramolecular SNAr reaction without a nitro group and the asymmetric synthesis of (-)-maldoxin by a catalytic enantioselective oxidative dearomatization of pestheic acid are described. The reactivity of (-)-maldoxin as a diene in the Diels-Alder reaction is also investigated.

DOI： 10.1021/acs.orglett.8b01502

Chiral Hypervalent Organoiodine-Catalyzed Enantioselective Oxidative Spirolactonization of Naphthol Derivatives 査読有り

Muhammet Uyanik, Takeshi Yasui, Kazuaki Ishihara

The Journal of Organic Chemistry 82 巻 ( 22 ) 頁： 11946 - 11953 2017年9月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

Highly enantioselective oxidative dearomatization of 2-naphthol derivatives was achieved for the first time by using conformationally flexible organoiodine catalysts derived from 2-aminoalcohol as a chiral source. Moreover, with the use of these catalysts, excellent enantioselectivities were also achieved for 1-naphthol derivatives, which had previously been obtained with only lower enantioselectivities. Furthermore, the product obtained from the present reaction could be transformed to a highly functionalized spirolactone in high yield and with excellent stereoselectivity.

DOI： 10.1021/acs.joc.7b01941

4,5-Dimethyl-2-Iodoxybenzenesulfonic Acid Catalyzed Site-Selective Oxidation of 2-Substituted Phenols to 1,2-Quinols 査読有り

Muhammet Uyanik, Tatsuya Mutsuga, Kazuaki Ishihara

Angewandte Chemie International Edition 56 巻 ( 14 ) 頁： 3956 - 3960 2017年2月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

A site-selective hydroxylative dearomatization of 2-substituted phenols to either 1,2-benzoquinols or their cyclodimers, catalyzed by 4,5-dimethyl-2-iodoxybenzenesulfonic acid with Oxone, has been developed. Furthermore, both the reaction rate and site selectivity could be further improved by the introduction of a trialkylsilylmethyl substituent at the 2-position of phenols. The corresponding 1,2-quinols could be transformed into various useful structural motifs by [4+2] cycloaddition cascade reactions.

DOI： 10.1002/anie.201612463

Ammonium Hypoiodite-Catalyzed Peroxidative Dearomatization of Phenols 招待有り査読有り

Muhammet Uyanik, Kohei Nishioka, Kazuaki Ishihara

Heterocycles 95 巻 ( 2 ) 頁： 1132 - 1147 2017年1月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

Here, we report the first transition metal-free peroxidative dearomatization of phenols using hypoiodite catalysis with TBHP. Hypoiodite salts are generated in situ from the corresponding quaternary ammonium iodides in the presence of TBHP, and the oxidative coupling reaction proceeds efficiently under mild conditions. The dearomatized products are versatile synthetic intermediates for further synthetic transformations to various complex structures including heterocycles. As a demonstration, the further oxidation of the unsaturated peroxide with TBHP afforded the corresponding peroxy epoxide in good yield.

DOI： 10.3987/COM-16-S(S)84

Enantioselective Synthesis of Masked Benzoquinones Using Designer Chiral Hypervalent Organoiodine(III) Catalysis 査読有り

Muhammet Uyanik, Niiha Sasakura, Masahiro Mizuno, Kazuaki Ishihara

ACS Catalysis 7 巻 ( 1 ) 頁： 872 - 876 2016年12月

キラル第四級アンモニウム次亜ヨウ素酸塩触媒招待有り

ウヤヌクムハメット, 石原一彰

月間ファインケミカル 45 巻 ( 12 ) 頁： 16 - 24 2016年12月

担当区分：筆頭著者,　責任著者記述言語：日本語掲載種別：研究論文（学術雑誌）

過酸化水素あるいはアルコール過酸化物の存在下、キラルヨウ化第四級アンモニウムからin situで調製される次亜ヨウ素酸塩を触媒活性種に用いるエナンチオ選択的酸化的環化反応を開発した。本酸化システムの詳細な触媒機構を解明することで、高活性な不斉有機酸化触媒システムの構築に成功し、多くの生物活性物質に含まれる2,3-ジヒドロベンゾフラン、クロマン、テトラヒドロフラン、及びスピロラクトン骨格の新規不斉合成を達成した。

Chiral Ammonium Hypoiodite Salt-Catalyzed Enantioselective Oxidative Cycloetherification to 2-Acyl Tetrahydrofurans 査読有り

Muhammet Uyanik, Hiroki Hayashi, Hirokazu Iwata, Kazuaki Ishihara

Chemistry Letters 45 巻 ( 3 ) 頁： 353 - 355 2016年1月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

2-Acyl tetrahydrofuran is a fundamental structure in natural products and pharmaceuticals. We achieved a chiral quaternary ammonium hypoiodite salt-catalyzed enantioselective oxidative cycloetherification of δ-hydroxyketone derivatives. The corresponding 2-acyl tetrahydrofurans were obtained in high chemical yield with high enantioselectivity.

DOI： 10.1246/cl.160004

Practical Oxidative Dearomatization of Phenols with Sodium Hypochlorite Pentahydrate 査読有り

Muhammet Uyanik, Niiha Sasakura, Mitsuyoshi Kuwahata, Yasukazu Ejima, Kazuaki Ishihara

Chemistry Letters 44 巻 ( 3 ) 頁： 381 - 383 2015年2月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

A highly efficient and practical oxidative dearomatization of phenols using sodium hypochlorite pentahydrate as an inexpensive, strong oxidant is reported for the first time. The oxidation reactions proceeded very rapidly in the presence of water to give the desired products in excellent yields, and sodium chloride and water were the only by-products derived from the oxidant.

DOI： 10.1246/cl.141130

High-Performance Hypoiodite/Hydrogen Peroxide Catalytic System for the Oxylactonization of Aliphatic γ-Oxocarboxylic Acids 査読有り

Muhammet Uyanik, Daisuke Suzuki, Mizu Watanabe, Hiroyasu Tanaka, Kikuo Furukawa, Kazuaki Ishihara

Chemistry Letters 44 巻 ( 3 ) 頁： 387 - 389 2015年2月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

Highly efficient hypoiodite-catalyzed oxylactonization of aliphatic γ-oxocarboxylic acids to the corresponding γ-acyl-γ-butyrolactones was developed. Highly dilute reaction conditions and slow addition of the oxidant are each highly effective for promoting the high-performance hypoiodite/hydrogen peroxide catalytic oxidation system.

DOI： 10.1246/cl.141110

Chiral Ammonium Hypoiodite-catalyzed Enantioselective Oxidative Dearomatization of 1-Naphthols Using Hydrogen Peroxide 査読有り

Muhammet Uyanik, Niiha Sasakura, Erina Kaneko, Kento Ohori, Kazuaki Ishihara

Chemistry Letters 44 巻 ( 2 ) 頁： 179 - 181 2015年2月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

A highly enantioselective oxidative dearomatization of 1-naphthol derivatives (Kita spirolactonization) catalyzed by chiral hypoiodite species prepared in situ from chiral quaternary ammonium iodide in the presence of hydrogen peroxide is reported.

DOI： 10.1246/cl.141012

High-turnover hypoiodite catalysis for asymmetric synthesis of tocopherols 査読有り

Muhammet Uyanik, Hiroki Hayashi, Kazuaki Ishihara

Science 345 巻 ( 6194 ) 頁： 291 - 294 2014年7月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

The diverse biological activities of tocopherols and their analogs have inspired considerable interest in the development of routes for their efficient asymmetric synthesis. Here, we report that chiral ammonium hypoiodite salts catalyze highly chemo- and enantioselective oxidative cyclization of γ-(2-hydroxyphenyl)ketones to 2-acyl chromans bearing a quaternary stereocenter, which serve as productive synthetic intermediates for tocopherols. Raman spectroscopic analysis of a solution of tetrabutylammonium iodide and tert-butyl hydroperoxide revealed the in situ generation of the hypoiodite salt as an unstable catalytic active species and triiodide salt as a stable inert species. A high-performance catalytic oxidation system (turnover number of ~200) has been achieved through reversible equilibration between hypoiodite and triiodide in the presence of potassium carbonate base. We anticipate that these findings will open further prospects for the development of high-turnover redox organocatalysis.

DOI： 10.1126/science.1254976

2-ヨードベンゼンスルホン酸(pre-IBS)とOxoneを用いる選択的酸化反応招待有り

ウヤヌクムハメット, 六鹿達矢, 石原一彰

和光純薬時報 81 巻 ( 4 ) 頁： 5 - 9 2013年10月

担当区分：筆頭著者記述言語：日本語掲載種別：研究論文（研究会，シンポジウム資料等）

著者らはIBXよりも遥かに活性が高く、選択性の優れたIBS触媒系を開発することができた。1–5 mol%のpre-IBSを用いて、第1級又は第2級アルコールを対応するアルデヒドやカルボン酸、またはケトンへ効率よく酸化できた。また、環状アルコールから触媒的カスケード型酸化反応によって環状エノンやラクトンを高収率で合成できた。さらに、本触媒的酸化システムをtert-アリルアルコールの転位／酸化反応及びフェノールのオルト選択的酸化反応に拡張することにも成功した。本IBS/Oxoneの触媒的酸化システムは、国内外の他の研究グループも加わり、さらに発展しつつある。今後も、触媒的IBS酸化はさらなる応用的発展が期待され、環境低負荷型酸化システムとして定着するであろう。

Hydrogen Bonding and Alcohol Effects in Asymmetric Hypervalent Iodine Catalysis: Enantioselective Oxidative Dearomatization of Phenols 査読有り

Muhammet Uyanik, Takeshi Yasui, Kazuaki Ishihara

Angewandte Chemie International Edition 52 巻 ( 35 ) 頁： 9215 - 9218 2013年6月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（学術雑誌）

A conformationally flexible C2-symmetric organoiodine(III) catalyst for the highly enantioselective catalytic oxidative dearomatization of phenols has been developed. Catalysis is controlled by intramolecular hydrogen-bonding interactions and additional achiral alcohols.

DOI： 10.1002/anie.201303559

Baeyer-Villiger Oxidation Using Hydrogen Peroxide 招待有り査読有り

Muhammet Uyanik, Kazuaki Ishihara

ACS Catalysis 3 巻 ( 5 ) 頁： 513 - 520 2013年2月

担当区分：筆頭著者記述言語：英語

The Baeyer-Villiger (BV) oxidation of carbonyl compounds to the corresponding esters or lactones is one of the most important transformations. We recently introduced a highly efficient and selective LiB(C6F5)4- or Ca[B(C6F5)4]2-catalyzed BV oxidation of ketones with aqueous hydrogen peroxide to give the corresponding lactones in high yield. In this perspective article, we focus on our discovery and the development of BV oxidation reactions and cascade oxidative transformations through representative metal catalysts and organocatalysts.

DOI： 10.1021/cs300821u

Conformationally-Flexible Chiral Hypervalent Organoiodine Catalysts for Enantioselective Oxidative Transformations 招待有り査読有り Open Access

Uyanik, M; Ishihara, K

JOURNAL OF SYNTHETIC ORGANIC CHEMISTRY JAPAN 70 巻 ( 11 ) 頁： 1116 - 1122 2012年11月

担当区分：責任著者記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Yuki Gosei Kagaku Kyokaishi/Journal of Synthetic Organic Chemistry

The development of chiral hypervalent iodine-catalyzed oxidative transformations is one of the most challenging areas in asymmetric organocatalysis. Although several elegant chiral hypervalent iodine(III and V) reagents or catalysts had been developed for various asymmetric oxidation reactions, the enantioselectivities had been moderate before our paper was published in 2010. We have had a great interest in the development of organocatalysis based on hypervalent chemistry since 2007. In this account, we describe our design concept of conformationally-flexible chiral hypervalent organoiodine(III), and the results obtained for catalytic use of our chiral iodines(III) for enantioselective Kita oxidative spirolactonization. Additionally, other chiral hypervalent iodine-mediated asymmetric oxidation reactions reported after our publications are also highlighted briefly.

DOI： 10.5059/yukigoseikyokaishi.70.1116

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