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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Baeyer-Villiger Oxidation and Oxidative Cascade Reactions with Aqueous Hydrogen Peroxide Catalyzed by Lipophilic Li[B(C₆F₅)₄] and Ca[B(C₆F₅)₄]₂ 査読有り

Muhammet Uyanik, Daisuke Nakashima, Kazuaki Ishihara

Angewandte Chemie International Edition 51 巻 ( 36 ) 頁： 9093 - 9096 2012年8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 have developed highly efficient and selective Li[B(C6F5)4] or Ca[B(C6F5)4]2 catalyzed Baeyer-Villiger (BV) oxidations of various cycloalkanones with 30-wt% aqueous hydrogen peroxide to give the corresponding lactones in high yield. Additionally, we have found that the reaction rate is accelerated with the use of oxalic acid as a co-catalyst. Moreover, beta-silyl cyclohexanones can be oxidized to either the corresponding unsaturated carboxylic acids or hydroxylactones in high yields through BV oxidation/b-elimination reaction sequences and subsequent epoxidation/cyclization reaction sequences, by controlling the amounts of H2O2 and oxalic acid. These reactions proceed under mild conditions and tolerate various functional groups.

DOI： 10.1002/anie.201204286

デザイン型ヨウ素触媒を用いる環境調和型選択的酸化反応査読有り

ウヤヌクムハメット

化学と工業 65 巻 ( 8 ) 頁： 625 - 626 2012年8月

担当区分：筆頭著者記述言語：日本語掲載種別：研究論文（大学，研究機関等紀要）

ヨウ素は容易に酸化されてその原子価を拡張し、超原子価状態となるため、遷移金属のような酸化・還元性を示す。我々は、ヨウ素のこの超原子価性に着目し、従来の毒性の強い重金属酸化剤や遷移金属触媒に代わる非金属系超原子価ヨウ素触媒による幾つかの高選択的環境調和型酸化反応の開発に成功した。

IBS-Catalyzed Regioselective Oxidation of Phenols to 1,2-Quinones with Oxone 招待有り査読有り

Muhammet Uyanik, Tatsuya Mutsuga, Kazuaki Ishihara

Molecules 17 巻 ( 7 ) 頁： 8604 - 8616 2012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）

We have developed the first example of hypervalent iodine(V)-catalyzed regioselective oxidation of phenols to ortho-quinones. Various phenols could be oxidized to the corresponding ortho-quinones in good to excellent yields using catalytic amounts of sodium salts of 2-iodobenzenesulfonic acids (pre-IBSes) and stoichiometric amounts of Oxone as a co-oxidant under mild conditions. The reaction rate of IBS-catalyzed oxidation under nonaqueous conditions was further accelerated in the presence of an inorganic base such as potassium carbonate (K2CO3), a phase transfer catalyst such as tetrabutylammonium hydrogen sulfate (n-Bu4NHSO4), and a dehydrating agent such as anhydrous sodium sulfate (Na2SO4).

DOI： 10.3390/molecules17078604

Catalysis with In Situ-Generated (Hypo)iodite Ions for Oxidative Coupling Reactions 招待有り査読有り

Muhammet Uyanik, Kazuaki Ishihara

ChemCatChem 4 巻 ( 2 ) 頁： 177 - 185 2011年12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）

This Concept highlights the discovery and development of oxidative coupling reactions catalyzed by the hypoiodite (IO) or iodite (IO2) ion, which are generated in situ from iodide (I-) ion with hydrogen peroxide or tert-butyl hydroperoxide as an environmentally benign oxidant. The most important features of these catalytic systems are 1) metal-free oxidation, 2) milder reaction conditions, 3) high chemoselectivity (they tolerate a wide range of various functional groups), 4) operational simplicity, and 5) water or tert-butyl alcohol as the only byproduct derived from the co-oxidant used.

DOI： 10.1002/cctc.201100352

2-Iodoxy-5-Methylbenzenesulfonic Acid-Catalyzed Selective Oxidation of 4-Bromobenzyl Alcohol to 4-Bromobenzaldehyde or 4-Bromobenzoic Acid with Oxone 招待有り査読有り

Muhammet Uyanik, Kazuaki Ishihara, Margaret Faul, Richard Crockett

Organic Syntheses 89 巻頁： 105 - 114 2011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）

We have reported that 2-iodoxybenzenesulfonic acids (IBSs) which are in situ prepared from Oxone and 2-iodobenzenesulfonic acids show efficient catalytic activity on the alcohol oxidation under mild conditions. Here, we succeeded in scale up of the IBS-catalyzed alcohol oxidations.

DOI： 10.15227/orgsyn.089.0105

In Situ Generated (Hypo)Iodite Catalysts for the Direct α-Oxyacylation of Carbonyl Compounds with Carboxylic Acids 査読有り

Muhammet Uyanik, Daisuke Suzuki, Takeshi Yasui, Kazuaki Ishihara

Angewandte Chemie International Edition 50 巻 ( 23 ) 頁： 5331 - 5334 2011年5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 intra- and intermolecular title reaction is catalyzed by an in situ generated ammonium (hypo)iodite species. Either H2O2 or tert-butyl hydroperoxide (TBHP) can be used as an environmentally benign oxidant and a wide range of substrates react to give the corresponding alpha-acyloxycarbonyl compounds in good to excellent yields.

DOI： 10.1002/anie.201101522

非共有結合相互作用を利用したキラル超原子価ヨウ素触媒の開発：北スピロラクトン化反応への応用招待有り

ウヤヌクムハメット, 安井猛, 石原一彰

和光純薬時報 79 巻 ( 2 ) 頁： 2-5 2011年4月

担当区分：筆頭著者記述言語：日本語

我々は2 , 6 -ジヒドロキシヨードベンゼンを基本骨格とし、乳酸をキラル源に柔軟な立体配座とC 2 対称性を保持したキラルヨードアレンの合理的設計を考案した。この有効性を実証するため、m -CPBA存在下、触媒量のヨードアレンから超原子価ヨウ素（III）触媒をin situ で調製し、1-ヒドロキシナフチルカルボン酸の北スピロラクトン化反応に試したところ、高い不斉収率で目的のスピロラクトンを得ることに成功した。現在、触媒前駆体は和光純薬から市販されている。本触媒技術で合成出来る光学活性スピロラクトンはさらに様々な合成変換が可能であることから、その応用範囲は広く、医薬品の製造技術としても期待される。これらの結果は、キラル超原子価ヨウ素化合物の設計、及びエナンチオ選択的酸化的カップリング反応の発展に大きく寄与するものと思われる。

In Situ-Generated Chiral Quaternary Ammonium (Hypo)iodite Catalysis for Enantioselective Oxidative Cyclisations 招待有り査読有り

Muhammet Uyanik, Kazuaki Ishihara

Chimica Oggi-Chemistry Today 29 巻 ( 1 ) 頁： 18 - 21 2011年1月

担当区分：筆頭著者記述言語：英語

Very recently, we developed the first enantioselective oxidative cycloetherification of ketophenols to 2-acyl-2,3-dihydrobenzofuran derivatives catalysed by in situ generated chiral quaternary ammonium (hypo)iodite with hydrogen peroxide or tert-butyl hydroperoxide (TBHP) as an environmentally benign ideal oxidant. The optically active
2-acyl 2,3-dihydrobenzofuran skeleton is a key structure in
several medicinally and biologically active compounds.

In situ-generated chiral quaternary ammonium (hypo)iodite catalysis for enantioselective oxidative cyclisations 招待有り査読有り

Uyanik, M; Ishihara, K

CHIMICA OGGI-CHEMISTRY TODAY 29 巻 ( 1 ) 頁： 18 - 21 2011年1月

2-Iodoxybenzenesulfonic Acid (IBS)-Catalyzed Oxidation of Alcohols 招待有り査読有り

43 巻 ( 3 ) 頁： 83 - 91 2010年12月

金属を使わない不斉酸化的カップリング触媒無機ヨウ素酸塩へのブレークスルー招待有り

石原一彰, UYANIK Muhammet

化学 65 巻 ( 10 ) 頁： 12 - 17 2010年9月

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）

触媒にキラルヨウ素酸塩を用い、共酸化剤に過酸化水素を用いた不斉分子内酸化的エーテル環化反応を開発した。金属を全く用いず、水のみを副生成物とする、常温、常圧下の理想的な不斉酸化的カップリングの成功である。本研究成果は2010年6月に米国科学誌「サイエンス」に掲載された)。本稿では、その開発の経緯、内容、意義について解説する。

Quaternary Ammonium (Hypo)iodite Catalysis for Enantioselective Oxidative Cycloetherification 査読有り

Muhammet Uyanik, Hiroaki Okamoto, Takeshi Yasui, Kazuaki Ishihara

Science 328 巻 ( 5984 ) 頁： 1376 - 1379 2010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）

It is desirable to minimize the use of rare or toxic metals for oxidative reactions in the synthesis of pharmaceutical products. Hypervalent iodine compounds are environmentally benign alternatives, but their catalytic use, particularly for asymmetric transformations, has been quite limited. We report here an enantioselective oxidative cycloetherification of ketophenols to 2-acyl-,3-dihydrobenzofuran derivatives, catalyzed by in situ generated chiral quaternary ammonium (hypo)iodite salts, with hydrogen peroxide as an environmentally benign oxidant. The optically active 2-acyl 2,3-dihydrobenzofuran skeleton is a key structure in several biologically active compounds.

DOI： 10.1126/science.1188217

Chiral Hypervalent Iodine-Catalyzed Enantioselective Oxidative Kita Spirolactonization of 1-Naphthol Derivatives and One-Pot Diastereoselective Oxidation to Epoxyspirolactones 招待有り査読有り

Muhammet Uyanik, Takeshi Yasui, Kazuaki Ishihara

Tetrahedron 66 巻 ( 31 ) 頁： 5841 - 5851 2010年4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 demonstrate here the rational design of a conformationally flexible C2-symmetric iodosylarene 8g based on secondary n-sigma* or hydrogen-bonding interactions as a chiral catalyst for the enantioselective Kita oxidative spirolactonization of 1-naphthol derivatives 5. Iodosylarenes 8 were generated in situ from iodoarenes 7 and mCPBA as a co-oxidant. Furthermore, epoxyspirolactone 15 was obtained by the one-pot oxidation of 5 with mCBPA in the presence of 7g. Thus, the enantioselective oxidation of 5 to 6 and the successive enantio- and diastereo-selective oxidation of 5 to 15 proceeded in good yields when we controlled the amount of mCPBA.

DOI： 10.1016/j.tet.2010.04.060

Enantioselective Kita Oxidative Spirolactonization Catalyzed by In Situ Generated Chiral Hypervalent Iodine(III) Species 査読有り

Muhammet Uyanik, Takeshi Yasui, Kazuaki Ishihara

Angewandte Chemie International Edition 49 巻 ( 12 ) 頁： 2175 - 2177 2010年3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）

Conformationally flexible C2-symmetric chiral iodosylarene, which has been rationally designed based on secondary n-σ* or hydrogen-bonding interactions, is a highly effective catalyst for the Kita oxidative spirolactonization. The present catalysis is applicable to a broader range of substrates and provides the highest enantioselectivity (up to 92% ee) among previous chiral hypervalent iodine-catalyzed reactions.

DOI： 10.1002/anie.200907352

Bromine-Catalyzed Aerobic Oxidation of Alcohols 招待有り査読有り

Muhammet Uyanik, Ryota Fukatsu, Kazuaki Ishihara

Chemistry-An Asian Journal 5 巻 ( 3 ) 頁： 456 - 460 2010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）

We demonstrated that a simple and environmentally benign catalytic system HBr/NaNO2 is very effective for the selective oxidation of alcohols under balloon pressure of O2. Furthermore, the aerobic oxidation of alcohols was also achieved under balloon pressure of air instead of pure O2 with this HBr/NaNO2/HNO3 catalytic system.

DOI： 10.1002/asia.200900609

2-Iodoxybenzenesulfonic Acid (IBS) Catalyzed Oxidation of Alcohols 招待有り査読有り

Uyanik, M; Ishihara, K

ALDRICHIMICA ACTA 43 巻 ( 3 ) 頁： 83 - 91 2010年

IBS-Catalyzed Oxidative Rearrangement of Tertiary Allylic Alcohols to Enones with Oxone 査読有り

Muhammet Uyanik, Ryota Fukatsu, Kazuaki Ishihara

Organic Letters 11 巻 ( 15 ) 頁： 3470 - 3473 2009年7月

Hypervalent iodine-catalyzed oxylactonization of ketocarboxylic acids to ketolactones 招待有り査読有り

Muhammet Uyanik, Takeshi Yasui, Kazuaki Ishihara

Bioorganic & Medicinal Chemistry Letters 19 巻 ( 14 ) 頁： 3848 - 3851 2009年4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 hypervalent iodine-catalyzed oxylactonization of ketocarboxylic acids to ketolactones was achieved in the presence of iodobenzene (10 mol%), p-toluenesulfonic acid monohydrate (20 mol%) and meta-chloroperbenzoic acid as a stoichiometric co-oxidant.

DOI： 10.1016/j.bmcl.2009.03.148

Hypervalent Iodine-Mediated Oxidation of Alcohols 招待有り査読有り

Muhammet Uyanik, Kazuaki Ishihara

Chemical Communications 2009 巻 ( 16 ) 頁： 2086 - 2099 2009年3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）

Over the past two decades there has been a dramatic increse in the use of hypervalent iodine compounds in synthetic organic chemistry due to their mild and selective oxidizing properties. Hypervalent iodine compounds catalyze various oxidation reactions such as the oxidation of alcohols, alpha-oxidation of ketones, oxidative spirocyclization of phenols, etc. Very recently, we found that 2-iodoxybenzensulfonic acid (IBS), which was generated from 2-iodobenzenesulfonic acid in situ, was an extremely active and mild catalyst for the highly chemoselective oxidation of various alcohols with powdered Oxone to carbonyl compounds such as aldehydes, carboxylic acids, ketones and cycloalkenones under nonaqueous conditions. In this review, we focus on the design of hypervalent iodine catalysts and review the discovery and development of the oxidation of alcohols with the stoichiometric or catalytic use of hypervalent iodine compounds.

DOI： 10.1039/b823399c

2-Iodoxybenzenesulfonic Acid as an Extremely Active Catalyst for the Selective Oxidation of Alcohols to Aldehydes, Ketones, Carboxylic Acids, and Enones with Oxone 査読有り国際誌

Uyanik, M; Akakura, M; Ishihara, K

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 131 巻 ( 1 ) 頁： 251 - 262 2009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）出版者・発行元：Journal of the American Chemical Society

Electron-donating group-substituted 2-iodoxybenzoic acids (IBXs) such as 5-Me-IBX (1g), 5-MeO-IBX (1h), and 4,5-Me2-IBX were superior to IBX 1a as catalysts for the oxidation of alcohols with Oxone (a trademark of DuPont) under nonaqueous conditions, although Oxone was almost insoluble in most organic solvents. The catalytic oxidation proceeded more rapidly and cleanly in nitromethane. Furthermore, 2-iodoxybenzenesulfonic acid (IBS, 6a) was much more active than modified IBXs. Thus, we established a highly efficient and selective method for the oxidation of primary and secondary alcohols to carbonyl compounds such as aldehydes, carboxylic acids, and ketones with Oxone in nonaqueous nitromethane, acetonitrile, or ethyl acetate in the presence of 0.05-5mol%of 6a, which was generated in situ from 2-iodobenzenesulfonic acid (7a) or its sodium salt. Cycloalkanones could be further oxidized to α,β- cycloalkenones or lactones by controlling the amounts of Oxone under the same conditions as above. When Oxone was used under nonaqueous conditions, Oxone wastes could be removed by simple filtration. Based on theoretical calculations, we considered that the relatively ionic character of the intramolecular hypervalent iodine-OSO2 bond of IBS might lower the twisting barrier of the alkoxyperiodinane intermediate 16. © 2009 American Chemical Society.

DOI： 10.1021/ja807110n

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論文 - ウヤヌク ムハメット

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論文 - ウヤヌク　ムハメット