著者は、財政支援のためにドイツ学術振興、バイエルファーマ社、ケムチュラ有機金属社Bergkamen、バイエルサービス社、BASF社、およびサソール社に感謝します。

1。チタン（IV） 第三の -butoxide/Triethylchlorosilane溶液の調製<ol><li>チタン（IV）t-ブトキシド（1mmol）の乾燥ジクロロメタン10ml中の400mgの（400μl）を溶解する。室温でこの溶液に150mgの（170μL）トリエチル（1ミリモル）を追加します。このジクロロメタン-溶液1mlを0.1ミリモルのチタン（IV）のtert-ブトキシド0.1ミリモルトリエチルが含まれています。 </li></ol> 2。テトラフェニル-1,2 - エタンジオールのピナコール反応（1）2 - エチルブチルアルデヒドと<ol><li>テトラフェニル-1,2 -エタンジオール（1,1 mmol）を3mlの無水ジクロロメタン中の新たに蒸留した2 -エチルブチ ​​ルアルデヒド（3ミリモル）、300mgの（370μl）を366 mgの問題。 </li><li>別途用意チタン（IV） 第三の -butoxide/triethylchlorosilane溶液（0.05ミリモル）の0.5ミリリットルを追加します。 </li><li>密閉反応管中で、室温で得られた混合物を撹拌した。 </li><li> CONFIシリカゲルTLCプレート（60 F254）上で - ます。rm反応を薄層クロマトグラフィー（9/1ヘキサン/アセトン溶離液）によって完成される。反応の終了は、テトラフェニル-1,2 -エタンジオールがもう1（〜12時間）を検出することができない時に到達される。製品のRf値は0.3 14である。 </li><li> 50mlのジクロロメタンで得られた反応混合物を希釈する。 </li><li>分液漏斗中で塩化アンモニウム水溶液と炭酸水素ナトリウム飽和溶液20ミリリットルずつ順次希釈した反応混合物を洗浄する。 </li><li>分液ロートで有機層を分離します。 </li><li>乾燥した硫酸マグネシウムで攪拌し、有機層を乾燥させる。 </li><li>溝付きペーパーフィルターで懸濁物をろ液およびろ液を収集します。 </li><li>ロータリーエバポレーター（10〜30 mmHgの）を使用して、40℃で真空中で濾液からジクロロメタンを除去。溶媒の蒸発は20分を必要とする。 </li><li>残った残留物を精製1,2 -ジオール2fの280ミリグラムを取得するヘキサン/アセトン（19:1から開始してダウン午後04時04へ行く）の勾配を用いてシリカゲル（0.035〜0.070ミリメートル、ACROS）のカラムを通してフラッシュカラムクロマトグラフィーによる（150ミリモル）を加えた。 </li><li>溶媒としてのCDCl 3を用いて1 H核磁気共鳴分光法（NMR）により、1,2 -ジオール2fの同一性を確認する。 300 MHzのNMR分光計のために、以下のように、ジオールの1 H NMRスペクトルである：δ= 0.78（のt、3H、J = 7.4 Hz）と0.87（のt、3H、J = 7.3 Hz）と、1.18から1.40（m個、4H）、1.75から1.81（mは、1H）、1.91（単数、1H、OH）、3.12（単数、1H、OH）、4.68mmolの（d、1H、J = 1.2 Hz）と、7.19から7.37（mは、6H ）、7.44から7.46（M、2H）​​、7.61から7.63（M、2H）​​。 </li></ol> 3。テトラフェニル-1,2 - エタンジオールのピナコール反応（1）ジエチルケトンと<ol><li> 3テトラフェニル-1,2 -エタンジオール（1,1）の366 mgおよびジエチルケトン（4ミリモル）345mgの（423μl）を解く乾燥ジクロロメタンをミリリットル。 </li><li>別途用意したチタン（IV） のtert -butoxide/triethylchloro-silane溶液（0.1ミリモル）の1ミリリットルを追加します。 </li><li>密閉反応管中で、室温で得られた混合物を撹拌した。 </li><li>反応物を確認する薄層クロマトグラフィー（溶離液：ヘキサン/アセトン、9:1）により完了したシリカゲルTLCプレート上で（60 F254）。反応の終了は、テトラフェニル-1,2 -エタンジオール1（〜12時間）を検出できない場合には、一度に到達する。製品のRfは0.3 14である。 </li><li> 50mlのジクロロメタンで得られた反応混合物を希釈する。 </li><li>分液漏斗中で塩化アンモニウム水溶液と炭酸ナトリウム溶液を20 mLの飽和したことにより、連続的に希釈した反応混合物を洗浄する。 </li><li>分液ロートで有機層を分離します。 </li><li>乾燥した硫酸マグネシウムで攪拌し、有機層を乾燥させる。 </li><li>溝付きの紙FILによってサスペンションをろ過するTERおよびろ液を収集します。 </li><li>ロータリーエバポレーター（10〜30 mmHgの）を使用して、40℃で真空下でジクロロメタンを除去。揮発性成分の蒸発は、30分を必要とする。 </li><li> 1 250mgのを取得する（19:1から開始してダウン午後04時04分になる）ヘキサン/アセトンの勾配でのシリカゲルのカラム（0.035〜0.070ミリメートル、ACROS）を介して、フラッシュカラムクロマトグラフィーによる残存する残留物を精製し、 2 -ジオールの4f（0.93ミリモル）を加えた。 </li><li>溶媒としてのCDCl 3を用いて1 H核磁気共鳴分光法（NMR）により、生成物の同一性を確認する。 、δ= 0.92（のt、6H、J = 7.6ヘルツ）、1.78（mは、4H）、2.03（単数、1H、OH）：300 MHzのNMR分光計のために、以下のように、ジオール4fの1 H NMRスペクトルである2.83（単数、1H、OH）、7.26から7.35（mは、6H）、7.69から7.71（m個、4H）。 </li></ol>

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Lett. 10, 3781-3784 (2008).</li><li>Maekawa, H., Yamamoto, Y., Shimada, H., Yonemura, K., Nishiguchi, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mg-+promoted+mixed+pinacol+coupling.">Mg- promoted mixed pinacol coupling.</a> Tetrahedron Lett. 45, 3869-3872 (2004).</li><li>Kang, M., Park, J., Pedersen, S. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pinacol+cross+coupling+reactions+of+ethyl+2-alkyl-2-formylpropionates.+stereoselective+synthesis+of+2,2,4-+trialkyl-3-hydroxy-&#947;-butyrolactones.">Pinacol cross coupling reactions of ethyl 2-alkyl-2-formylpropionates. stereoselective synthesis of 2,2,4- trialkyl-3-hydroxy-&#947;-butyrolactones.</a> Syn. Lett. , 41-43 (1997).</li><li>Askham, F. R., Carroll, K. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Anionic+zirconaoxiranes+as+nucleophilic+aldehyde+equivalents.+application+to+intermolecular+pinacol+cross+coupling.">Anionic zirconaoxiranes as nucleophilic aldehyde equivalents. application to intermolecular pinacol cross coupling.</a> J. Org. Chem. 58, 7328-7329 (1993).</li><li>Hou, Z., Takamine, K., Aoki, O., Shiraishi, H., Fujiwara, Y., Taniguchi, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nucleophilic+Addition+of+lanthanoid+metal+umpoled+diaryl+ketones+to+electrophiles.">Nucleophilic Addition of lanthanoid metal umpoled diaryl ketones to electrophiles.</a> J. Org. Chem. 53, 6077-6084 (1988).</li><li>Groth, U., Jung, M., Vogel, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intramolecular+chromium(II)-catalyzed+pinacol+cross+coupling+of+2-Mmethylene-&#945;,&#969;-dicarbonyls.">Intramolecular chromium(II)-catalyzed pinacol cross coupling of 2-Mmethylene-&#945;,&#969;-dicarbonyls.</a> Syn. Lett. , 1054-1058 (2004).</li><li>Appendino, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+of+Modified+Ingenol+Esters.">Synthesis of Modified Ingenol Esters.</a> Eur. J. Org. Chem. , 3413-3420 (1999).</li><li>Spaccini, R., Pastori, N., Clerici, A., Punta, C., Porta, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Key+role+of+Ti(IV)+in+the+selective+radical-radical+cross-coupling+mediated+by+the+Ingold-Fischer+effect.">Key role of Ti(IV) in the selective radical-radical cross-coupling mediated by the Ingold-Fischer effect.</a> J. Am. Chem. Soc. 130, 18018-18024 (2008).</li><li>Leonard, J., Lyfo, B., Procter, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Advanced Practical Organic Chemistry. , (2013).</li><li>Scheffler, U., Stoesser, R., Mahrwald, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Retropinacol+/+cross-pinacol+coupling+reactions+-+a+catalytic+access+to+1,2-unsymmetrical+diols.">Retropinacol / cross-pinacol coupling reactions - a catalytic access to 1,2-unsymmetrical diols.</a> Adv. Synth. Cat. 354, 2648-2652 (2012).</li></ol>

著者らは、競合する経済的利益を宣言していません。

反応時間および高い収率の全体的な減少は、電子が豊富なカルボニル化合物（17エントリ3を比較する、 表1または13のエントリ19、 表2）の配置によって観察される。また、嵩高い置換基を持つケトンの反応における収率の低下は（11、 表2にエントリ12を比較）比較可能な条件下で観察されている。 カルボニル化?...

ピナカップリング反応は、対称的にビシナルジオール（1,2 - ジオール、ピナコール）の調製のための一般的かつ一般的に使用される方法である。この分野での包括的なレビューは参考文献平尾1、チャタジーと女子2、Ladipo 3、およびGansäuerとブルーム4を参照してください。それとは対照的に、少数の報告が対応する非対称1,2 -ジオール（チタン（IV）クロリド/ 5マンガン、サマリウム（II）、ヨウ6、マグネシウムを得クロスピナコールカップリング反応の効率的な実現を指すために出版された/ 7トリメチルクロロシラン、バナジウム（II）8、ジルコニウム/スズ9、及びイッテルビウム10）。したがって、分子間ピナコールカップリング反応は、依然として、有機化学においてこの変換の実行、特に、触媒の大きな課題である。 クロスカップリング生成物の形成は、動力学的に不利である古典ピナコールカップリングの条件の下で。非対称生成物の十分な量を得るためにはつのカルボニル化合物の添加が可能である遅延。そこにこの概念を開発しているいくつかの例が存在するが、それらはいくつかの具体的な実験操作に基づいているので、一般化することはできません。また、これらの変換中の1つのカルボニル化合物の必要な過剰は、複雑な生成物混合物11の面倒な分離をもたらした。この目的のための代替案が必要な追加の試薬の等モル量をレンダリングする一方の反応のprecomplexationによって表される。 可逆ピナコール反応の様々な例12に記載されている。これらは、そのような状態は、クロスカップリング生成物を選択的に合成するための最適な出発点となる可能性があることを考慮につながる。低原子価金属、ならびに反応性ラジカル種をin situで同時に形成されるので、非対称ジオールが好適カルボニル反応物質の存在下で排他的に形成することができる。 （ポルタら AIBN生成するために、化学量論量のさらなる展開（2,2 &#39; -アゾ-ビス-イソブチロニトリル）で匹敵するピナコール切断およびその後のカップリングを記載する前に、我々の知る限り、このような方法が報告されていない必要なラジカル）13。 ここにプロトコルは、非対称1,2 - ジオールへの迅速かつ簡単な操作上のアクセスを提供する可視化される。非対称ピナ製品は、優れた収率（&gt; 95％）で主にアクセス可能である。望ましくない対称ピナコール製品が観察されない。この新しいクロスピナ方法論はretropinacol /クロスピナコールカップリング配列に基づいている。これは、代表的なベンゾピナコールの反応（1,1,2,2 -テトラフェニル-1,2 -エタンジオール、1）（アルデヒド直列）2 -エチルブチ ​​ルアルデヒドと、wが、以下に実証される（ケトン系）でi番目のジエチル。

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:363px;">1.2-Dichloromethane</td>
			<td style="width:179px;">Sigma-Aldrich</td>
			<td style="width:137px;">319929</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Titanium(IV)tert-butoxide</td>
			<td>VWR International</td>
			<td>200014-852</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">2-Ethylbutyraldehyde</td>
			<td>Sigma-Aldrich</td>
			<td>110094</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Benzopinacol</td>
			<td>Aldrich</td>
			<td>B9807</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Triethylchlorosilane</td>
			<td>Aldrich</td>
			<td>&#160;235067</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">hexane, certified ACS</td>
			<td>Fisher scientific</td>
			<td>H29220</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">acetone, certified ACS</td>
			<td>ACROS</td>
			<td>42324</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Ammonium chloride</td>
			<td>ACROS</td>
			<td>19997</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Sodium hydrogen carbonate</td>
			<td>ACROS</td>
			<td>12336</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Magnesium sulphate</td>
			<td>ACROS</td>
			<td>41348</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="26">
			<td height="26" style="height:26px;">silica gel 60 F254 TLC plates</td>
			<td>VWR International</td>
			<td>1,057,140,001</td>
			<td style="width:79px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">&#160;silica gel, 0.035-0.070 for flash-chromatography</td>
			<td>ACROS</td>
			<td>240360300</td>
			<td style="width:79px;"></td>
		</tr>
	</tbody>
</table>

retropinacol/cross-pinacol coupling reactions - a catalytic access to 1,2-unsymmetrical diols

非対称1,2 - ジオールは、還元的ピナコールカップリングプロセスによってほとんどアクセスできます。このような変換が正常に実行されたが、明確な認識と2同じようなカルボニル化合物（第三の1,2 - ジオール→二の1,2 - ジオール又はケトン→アルデヒド）の厳密な区別にバインドされています。この微調整は、依然として有機化学者にとっての課題と未解決の問題である。そこにこの変換が正常に実行に関するいくつかの報告が存在するが、それらは一般化することはできません。ここに我々はretropinacol /クロスピナコールカップリング配列を介して進行する触媒の直接ピナコールカップリングプロセスについて説明します。このように、非対称置換1,2 - ジオールは、非常に穏やかな条件の下で操作上の簡単な性能によってほぼ定量的収率でアクセスすることができます。このようなシリンジポンプ技術または反応を遅延させた添加物などの人工技術は必要ありません。我々が説明する手順では、と非常に迅速なアクセスを提供しますクロスピナ製品（1,2 - ジオール、隣接ジオール）。エナンチオ選択的パフォーマンスなど 、この新しい方法の更なる延長は、非対称キラル1,2 -ジオールの合成のために非常に有用なツールを提供することができます。

チタン触媒量の（IV）アルコキシドの存在下でテトラフェニル-1,2 -エタンジオール1とアセトンの反応では、1,1 -ジフェニル-1,2 -ジオール4aと同時に形成の形成が観察されベンゾフェノン3の（ スキーム1）。アセトンの競争力のピナコールカップリングによって形成され、対応する対称的な1,2 - ジオールは検出されなかった。しかしながら、定...

Watch this Scientific Journal Video about Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols at JoVE.com

Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols

retropinacol /クロスピナコールカップリング機構に基づいて、非対称の1,2 - ジオールの合成のための新規のアカウントが記述されている。このため反応の触媒的執行に従来のクロスピナコールカップリングに比べて大幅な改善が達成される。

Retropinacol /クロスピナコールカップリング反応 -  1,2  - 非対称ジオールに対して触媒のアクセス

Unsymmetrical 1,2-diols are hardly accessible by reductive pinacol coupling processes. A successful execution of such a transformation is bound to a clear ...

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Alcohols and Phenols

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12.9K ビュー.  Humboldt University of Berlin.  retropinacol /クロスピナコールカップリング機構に基づいて、非対称の1,2 - ジオールの合成のための新規のアカウントが記述されている。このため反応の触媒的執行に従来のクロスピナコールカップリングに比べて大幅な改善が達成される。 

ビデオ: Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols

Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-(phosphinetriyl)tripiperidine]}palladium Under Mild Reaction Conditions

Dichloro-bis(aminophosphine) complexes of palladium with the general formula of [(P{(NC5H10)3-n(C6H11)n})2Pd(Cl)2] (where n = 0-2), belong to a new family of easy accessible, very cheap, and air stable, but highly active and universally applicable C-C cross-coupling catalysts with an excellent functional group tolerance. Dichloro{bis[1,1',1''-(phosphinetriyl)tripiperidine]}palladium [(P(NC5H10)3)2Pd(Cl)2] (1), the least stable complex within this series towards protons; e.g. in the form of water, allows an eased nanoparticle formation and hence, proved to be the most active Heck catalyst within this series at 100 &#176;C and is a very rare example of an effective and versatile catalyst system that efficiently operates under mild reaction conditions. Rapid and complete catalyst degradation under work-up conditions into phosphonates, piperidinium salts and other, palladium-containing decomposition products assure an easy separation of the coupling products from catalyst and ligands. The facile, cheap, and rapid synthesis of 1,1',1"-(phosphinetriyl)tripiperidine and 1 respectively, the simple and convenient use as well as its excellent catalytic performance in the Heck reaction at 100 &#176;C make 1 to one of the most attractive and greenest Heck catalysts available.
We provide here the visualized protocols for the ligand and catalyst syntheses as well as the reaction protocol for Heck reactions performed at 10 mmol scale at 100 &#176;C and show that this catalyst is suitable for its use in organic syntheses.

Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1&#039;,1&#039;&#039;-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions

Dichloro{bis[1,1',1''-(phosphinetriyl)tripiperidine]}palladium [(P(NC5H10)3)2Pd(Cl)2] (1) is an easy accessible, cheap, and air stable, but highly active Heck catalyst with an excellent functional group tolerance that efficiently operates under mild reaction conditions to give the coupling products in very high yields.

温和な反応条件の下でパラジウム - ジクロロ{ビス[（ホスフィントリ）tripiperidine 1,1 &#39;、1&#39;&#39;]}触媒による溝呂木 - ヘッククロスカップリング反応

Dichloro-bis(aminophosphine) complexes of palladium with the general formula of [(P{(NC5H10)3-n(C6H11)n})2Pd(Cl)2] (where n = 0-2), belong to a new family ...

化学

Hot Biological Catalysis: Isothermal Titration Calorimetry to Characterize Enzymatic Reactions

Isothermal titration calorimetry (ITC) is a well-described technique that measures the heat released or absorbed during a chemical reaction, using it as an intrinsic probe to characterize virtually every chemical process. Nowadays, this technique is extensively applied to determine thermodynamic parameters of biomolecular binding equilibria. In addition, ITC has been demonstrated to be able of directly measuring kinetics and thermodynamic parameters (kcat, KM, &#916;H) of enzymatic reactions, even though this application is still underexploited. As heat changes spontaneously occur during enzymatic catalysis, ITC does not require any modification or labeling of the system under analysis and can be performed in solution. Moreover, the method needs little amount of material. These properties make ITC an invaluable, powerful and unique tool to study enzyme kinetics in several applications, such as, for example, drug discovery.
In this work an experimental ITC-based method to quantify kinetics and thermodynamics of enzymatic reactions is thoroughly described. This method is applied to determine kcat and KM of the enzymatic hydrolysis of urea by Canavalia ensiformis (jack bean) urease. Calculation of intrinsic molar enthalpy (&#916;Hint) of the reaction is performed. The values thus obtained are consistent with previous data reported in literature, demonstrating the reliability of the methodology.

Isothermal titration calorimetry measures heat flow released or absorbed in chemical reactions. This method can be used to quantify enzyme-catalysis. In this paper, the protocol for instrumental setup, experiment running, and data analysis is generally described, and applied to the characterization of enzymatic urea hydrolysis by jack bean urease.

ホット生物触媒：等温滴定熱量測定酵素反応を特徴づけるために

Isothermal titration calorimetry (ITC) is a well-described technique that measures the heat released or absorbed during a chemical reaction, using it as ...

Amide Coupling Reaction for the Synthesis of Bispyridine-based Ligands and Their Complexation to Platinum as Dinuclear Anticancer Agents

Amide coupling reactions can be used to synthesize bispyridine-based ligands for use as bridging linkers in multinuclear platinum anticancer drugs. Isonicotinic acid, or its derivatives, are coupled to variable length diaminoalkane chains under an inert atmosphere in anhydrous DMF or DMSO with the use of a weak base, triethylamine, and a coupling agent, 1-propylphosphonic anhydride. The products precipitate from solution upon formation or can be precipitated by the addition of water. If desired, the ligands can be further purified by recrystallization from hot water. Dinuclear platinum complex synthesis using the bispyridine ligands is done in hot water using transplatin. The most informative of the chemical characterization techniques to determine the structure and gross purity of both the bispyridine ligands and the final platinum complexes is 1H NMR with particular analysis of the aromatic region of the spectra (7-9 ppm). The platinum complexes have potential application as anticancer agents and the synthesis method can be modified to produce trinuclear and other multinuclear complexes with different hydrogen bonding functionality in the bridging ligand.

This protocol describes the use of amide coupling reactions of isonicotinic acid and diaminoalkanes to form bridging ligands suitable for use in the synthesis of multinuclear platinum complexes, which combine aspects of the anticancer drugs BBR3464 and picoplatin.

ビスピリジン系リガンドの合成と二核抗癌剤として白金彼らの複合体形成のためのアミドカップリング反応

Amide coupling reactions can be used to synthesize bispyridine-based ligands for use as bridging linkers in multinuclear platinum anticancer drugs. ...

Synthesis and Catalytic Performance of Gold Intercalated in the Walls of Mesoporous Silica

As a promising catalytically active nano reactor, gold nanoparticles intercalated in mesoporous silica (GMS) were successfully synthesized and properties of the materials were investigated. We used a one pot sol-gel approach to intercalate gold nano particles in the walls of mesoporous silica. To start with the synthesis, P123 was used as template to form micelles. Then TESPTS was used as a surface modification agent to intercalate gold nano particles. Following this process, TEOS was added in as a silica source which underwent a polymerization process in acid environment. After hydrothermal processing and calcination, the final product was acquired. Several techniques were utilized to characterize the porosity, morphology and structure of the gold intercalated mesoporous silica. The results showed a stable structure of mesoporous silica after gold intercalation. Through the oxidation of benzyl alcohol as a benchmark reaction, the GMS materials showed high selectivity and recyclability.

Here, we present a protocol with a sol-gel process to synthesize gold intercalated in the walls of mesoporous materials (GMS), which is confirmed to possess a mesoporous matrix with gold intercalated in the walls imparting great stability and recyclability.

合成とメソポーラスシリカの壁に金インターカレーの触媒性能

As a promising catalytically active nano reactor, gold nanoparticles intercalated in mesoporous silica (GMS) were successfully synthesized and properties ...

Real-time Monitoring of Reactions Performed Using Continuous-flow Processing: The Preparation of 3-Acetylcoumarin as an Example

By using inline monitoring, it is possible to optimize reactions performed using continuous-flow processing in a simple and rapid way. It is also possible to ensure consistent product quality over time using this technique. We here show how to interface a commercially available flow unit with a Raman spectrometer. The Raman flow cell is placed after the back-pressure regulator, meaning that it can be operated at atmospheric pressure. In addition, the fact that the product stream passes through a length of tubing before entering the flow cell means that the material is at RT. It is important that the spectra are acquired under isothermal conditions since Raman signal intensity is temperature dependent. Having assembled the apparatus, we then show how to monitor a chemical reaction, the piperidine-catalyzed synthesis of 3-acetylcoumarin from salicylaldehyde and ethyl acetoacetate being used as an example. The reaction can be performed over a range of flow rates and temperatures, the in-situ monitoring tool being used to optimize conditions simply and easily.

Real-time monitoring allows for fast optimization of reactions performed using continuous-flow processing. Here the preparation of 3-acetylcoumarin is used as an example. The apparatus for performing in-situ Raman monitoring is described, as are the steps required to optimize the reaction.

連続フロー処理を​​使用して行われる反応のリアルタイムモニタリング：例として3- Acetylcoumarinの調製

By using inline monitoring, it is possible to optimize reactions performed using continuous-flow processing in a simple and rapid way. It is also possible ...

Highly Stereoselective Synthesis of 1,6-Ketoesters Mediated by Ionic Liquids: A Three-component Reaction Enabling Rapid Access to a New Class of Low Molecular Weight Gelators

In organic chemistry ionic liquids (ILs) have emerged as safe and recyclable reaction solvents. In the presence of a base ILs can be deprotonated to form catalytically active N-Heterocyclic Carbenes (NHCs). Here we have used ILs as precatalysts in the addition of &#945;,&#946;-unsaturated aldehydes to chalcones to form 1,6-ketoesters, incorporating an anti-diphenyl moiety in a highly stereoselective fashion. The reaction has a broad substrate scope and several functional groups and heteroaromatics can be integrated into the ketoester backbone in generally good yields with maintained stereoselectivity. The reaction protocol is robust and scalable. The starting materials are inexpensive and the products can be obtained after simple filtration, avoiding solvent-demanding chromatography. Furthermore, the IL can be recycled up to 5 times without any loss of reactivity. Moreover, the 1,6-ketoester end product is a potent gelator in several hydrocarbon based solvents. The method enables rapid access to and evaluation of a new class of low molecular weight gelators (LMWGs) from recyclable and inexpensive starting materials.

Ionic liquids (ILs) mediate fast, simple and cheap access to 1,6-ketoesters in high diastereoselectivities and good yields. The reaction protocol is robust and the 1,6-ketoesters can be obtained in gram scale after a simple filtration protocol. Moreover, the 1,6-ketoesters are potent gelators in hydrocarbon solvents.

イオン液体によって媒介1,6-ケトエステルの高立体選択的合成：低分子ゲル化剤の新しいクラスへの迅速なアクセスを有効にする三成分の反応

In organic chemistry ionic liquids (ILs) have emerged as safe and recyclable reaction solvents. In the presence of a base ILs can be deprotonated to form ...

Laboratory Production of Biofuels and Biochemicals from a Rapeseed Oil through Catalytic Cracking Conversion

The work is based on a reported study which investigates the processability of canola oil (bio-feed) in the presence of bitumen-derived heavy gas oil (HGO) for production of transportation fuels through a fluid catalytic cracking (FCC) route. Cracking experiments are performed with a fully automated reaction unit at a fixed weight hourly space velocity (WHSV) of 8 hr-1, 490-530 &#176;C, and catalyst/oil ratios of 4-12 g/g. When a feed is in contact with catalyst in the fluid-bed reactor, cracking takes place generating gaseous, liquid, and solid products. The vapor produced is condensed and collected in a liquid receiver at -15 &#176;C. The non-condensable effluent is first directed to a vessel and is sent, after homogenization, to an on-line gas chromatograph (GC) for refinery gas analysis. The coke deposited on the catalyst is determined in situ by burning the spent catalyst in air at high temperatures. Levels of CO2 are measured quantitatively via an infrared (IR) cell, and are converted to coke yield. Liquid samples in the receivers are analyzed by GC for simulated distillation to determine the amounts in different boiling ranges, i.e., IBP-221 &#176;C (gasoline), 221-343 &#176;C (light cycle oil), and 343 &#176;C+ (heavy cycle oil). Cracking of a feed containing canola oil generates water, which appears at the bottom of a liquid receiver and on its inner wall. Recovery of water on the wall is achieved through washing with methanol followed by Karl Fischer titration for water content. Basic results reported include conversion (the portion of the feed converted to gas and liquid product with a boiling point below 221 &#176;C, coke, and water, if present) and yields of dry gas (H2-C2's, CO, and CO2), liquefied petroleum gas (C3-C4), gasoline, light cycle oil, heavy cycle oil, coke, and water, if present.

This paper presents an experimental method to produce biofuels and biochemicals from canola oil mixed with a fossil-based feed in the presence of a catalyst at mild temperatures. Gaseous, liquid, and solid products from a reaction unit are quantified and characterized. Conversion and individual product yields are calculated and reported.

接触分解変換により菜種油からバイオ燃料および生化学の研究室の生産

The work is based on a reported study which investigates the processability of canola oil (bio-feed) in the presence of bitumen-derived heavy gas oil ...

A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes

Norbornene can be polymerized by a variety of mechanisms, including insertion polymerization whereby the double bond is polymerized and the bicyclic nature of the monomer is conserved. The resulting polymer, polynorbornene, has a very high glass transition temperature, Tg, and interesting optical and electrical properties. However, the polymerization of functional norbornenes by this mechanism is complicated by the fact that the endo substituted norbornene monomer has, in general, a very low reactivity. Furthermore, the separation of the endo substituted monomer from the exo monomer is a tedious task. Here, we present a simple protocol for the polymerization of substituted norbornenes (endo:exo ca. 80:20) bearing either a carboxylic acid or a pendant double bond. The process does not require that both isomers be separated, and proceeds with low catalyst loadings (0.01 to 0.02 mol%). The polymer bearing pendant double bonds can be further transformed in high yield, to afford a polymer bearing pendant epoxy groups. These simple procedures can be applied to prepare polynorbornenes with a variety of functional groups, such as esters, alcohols, imides, double bonds, carboxylic acids, bromo-alkyls, aldehydes and anhydrides.

We describe the catalytic insertion polymerization of 5-norbornene-2-carboxylic acid and 5-vinyl-2-norbornene to form functional polymers with a very high glass transition temperature.

機能性ノルボルネンの触媒挿入重合のためのシンプルで効率的なプロトコル

Norbornene can be polymerized by a variety of mechanisms, including insertion polymerization whereby the double bond is polymerized and the bicyclic ...

A Protocol for Safe Lithiation Reactions Using Organolithium Reagents

Organolithium reagents are powerful tools in the synthetic chemist&#39;s toolbox. However, the extreme pyrophoric nature of the most reactive reagents warrants proper technique, thorough training, and proper personal protective equipment. To aid in the training of researchers using organolithium reagents, a thorough, step-by-step protocol for the safe and effective use of tert-butyllithium on an inert gas line or within a glovebox is described. As a model reaction, preparation of lithium tert-butyl amide by the reaction of tert-butyl amine with one equivalent of tert-butyl lithium is presented.

The safe and proper use of organolithium reagents is described.

有機リチウム試薬を用いて安全なリチウム化反応のためのプロトコル

Organolithium reagents are powerful tools in the synthetic chemist&#39;s toolbox. However, the extreme pyrophoric nature of the most reactive reagents ...

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions

Detailed and generalized protocols are presented for the synthesis and subsequent purification of four palladium N-heterocyclic carbene complexes from benzimidazolium salts. Detailed and generalized protocols are also presented for testing the catalytic activity of such complexes in arylation and Suzuki-Miyaura cross-coupling reactions. Representative results are shown for the catalytic activity of the four complexes in arylation and Suzuki-Miyaura type reactions. For each of the reactions investigated, at least one of the four complexes successfully catalyzed the reaction, qualifying them as promising candidates for catalysis of many carbon-carbon bond-forming reactions. The protocols presented are general enough to be adapted for the synthesis, purification and catalytic activity testing of new palladium N-heterocyclic carbene complexes.

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions

Detailed and generalized protocols are presented for the synthesis and subsequent purification of four palladium N-heterocyclic carbene complexes from benzimidazolium salts. The complexes were tested for catalytic activity in arylation and Suzuki-Miyaura reactions. For each reaction investigated, at least one of the four complexes successfully catalyzed the reaction.

パラジウム<em&gt; N</em&gt; - 複素環カルベン錯体：ベンズイミダゾリウム塩からの合成と炭素 - 炭素結合形成反応における触媒活性

Detailed and generalized protocols are presented for the synthesis and subsequent purification of four palladium N-heterocyclic carbene complexes from ...