Dr. B.P.S. Chauhan would like to gratefully acknowledge William Paterson University for assigned release time (ART) award for part of the research described here and also for the research program in general.

注：さらに精製することなく、メーカーからのものであるように、すべての試薬が使用されています。反応は、完全な還元を確実にするために、UV-可視分光法を介して、最大1週間モニターしました。全ての反応は、通気フードの下で行われ、適切な安全服装は手袋、眼ゴーグル、及び白衣など、常時装着されます。 銀ナノ粒子の1の合成<ol><li>直接50ミリリットルの三角フラスコに硝酸銀の0.0169グラム（0.1ミリモル）を秤量。 </li><li> 20超純水の18.2MΩのミリリットルとマグネチックスターラーバーに追加します。蒸発を防ぐために、栓でフラスコをカバーしています。 </li><li>油浴に入れフラスコに攪拌機/ホットプレート上に位置し、その温度が60℃に維持されていることを確認します。 </li><li>ゆっくり精密マイクロピペットを用いて、2-ASTの144μL（0.2ミリモル）を追加します。すべてのシランを確保するため、溶液中のフラッシュピペットで数回溶液に移します。 </li><li>紫外可視分光測定値を取りますセクション5に記載されているプロトコルに従って。 </li><li> 6時間後、油浴からサンプルを削除し、ストレージ、TEM、FTIR、さらなる分析のために20ミリリットルのサンプルバイアルに移します。 注：金とパラジウムナノ粒子の合成は、216μL（0.3 mmol）の2-ASTを必要とする金ナノ粒子を除いて同じ方法および化学量論的な量に従います。反応は、最大2週間のナノ粒子を製造し続けることができるが、速度は初期速度と比較して有意ではありません。 </li></ol> 2.透過型電子顕微鏡（TEM）サンプル調製<ol><li>サンプルを室温まで冷却していることを確認してください。 </li><li>フィルター清潔なろ紙上に200カーボンメッシュホルムバール被覆銅グリッドを配置します。 </li><li> 1ミリリットルプラスチック製パスツールピペット、キャストドロップ直接グリッド上にナノ粒子サンプルの約60μLを使用しました。 </li><li>グリッドが撮影前に24時間乾燥することができます。 </li><li>以下の条件を用いて高解像度のTEM画像を取ります。10μAの電流および電圧22を加速 100 kVの。 </li></ol> 3.核磁気共鳴（NMR）試料の調製注：RTでNMRを実行します。高温では信号が得られたスペクトルの品質を劣化させる、合体することがあります。 <ol><li>きれいなNMRチューブに精密ピペット、ピペット重水素ガス（D 2 O）の50μLを使用しました。 </li><li>別のクリーン精密ピペットと、同じNMRチューブにピペットナノ粒子サンプルの400μLを。 <ol><li>サンプルはNMR管の内壁に付着することがあるように、ゆっくりとNMRチューブにソリューションを追加します。サンプルが付着しない場合は、チューブをキャップと底部への解決策を強制するために、チューブの上部を横に振ります。 </li></ol></li><li>揺れを繰り返しNMRチューブを反転させて、サンプルを混ぜます。 </li><li>製造元によって提供さNMRプロトコルによって設定された指示に従ってNMRに置き、試料管。千スキャンの上方には、適切な解像度のために必要があるかもしれません1 HプロトンNMRパルスプログラムでolution。 注：NMR管の壁はきれいでなければなりません。チューブの外壁は、スペクトルの明確化のために、分析前にマイクロファイバーや糸くずの出ない布で拭くことをお勧めします。 </li><li>終了時にサンプルを捨てます。親液にサンプルを返さないでください。 </li></ol> 4.フーリエ変換赤外（FTIR）分光法サンプル調製を変換します<ol><li>小さなガラス容器にナノ粒子サンプルの2ミリリットルを置きます。 3ミリリットル管や1ドラムガラスバイアルはうまく動作します。 </li><li>コックを装着した真空デシケーター中でガラス容器を配置することによって、サンプルを乾燥させます。 </li><li>真空ポンプ装置にデシケーターを取り付けます。サンプルの乾燥は真空の強さに応じて数時間かかる場合があります。コンテナ内の目に見える液体が存在しない後の試料を乾燥考えてみましょう。 </li><li>きれいなへらを使用してサンプルを下にこすり落とし、固体材料を集めます。 </li><li> ZnSe crystを装着ATR-FTIR分光器の上に固体材料を置き、らのダイオードレーザ。 </li><li> 4,000-500 cm -1で2.0のスペクトル分解能との間の32スキャンを統合するFTIRスペクトルを取得します。エアバックグラウンド23を使用してください。 </li></ol> 5.紫外可視分光法サンプル調製<ol><li>その飽和が分光計分析では発生しませんので、水にナノ粒子サンプルの1〜10個の希釈されているナノ粒子のサンプルに紫外可視分光法を実施します。 </li><li>反応は半時間間隔で実行されている間、UV-Visのためのナノ粒子のサンプルを削除してください。 </li><li>精密ピペットを用いて、ナノ粒子材料の100μlのを削除し、プラスチック製キュベットに配置します。 </li><li>同じキュベットに超純水の1ミリリットルを加え、ピペットを数回洗浄することにより十分に混合します。 </li><li> 250から800 nmの間の録音紫外可視吸収スペクトル。 </li><li>分析の後、反応にサンプルを返しません。適切な方法で分析物を処分。 </li></ol>

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競合する金融利害関係はありません。

本論文で報告された塩は、その金属で試験された唯一の塩です。その結果、この反応戦略は、金属のすべての塩、特に金で動作するであろうことが不確実です。水中のこれらの塩の溶解度は、反応時間、形態、及び収率の観点から、反応の結果に影響を及ぼし得ます。全ての反応においては、シランは、既に溶解した金属塩溶液に添加しました。 注意がこれらの反応は?...

デザイナーのナノ材料は増加の需要やアプリケーションなど、そのように合成する種々の方法を実行します。例えば、レーザアブレーションまたは化学エッチングのような「トップダウン」方法は、その優れた制御性および信頼性サブミクロンレベルまで材料を解決する能力のために使用されてきました。これらの方法は、所望のナノ構造のサイズが減少するにつれて、典型的には製造コストを増大させる細かい部品に加工するバルク材料に依存しています。これまで合成の別の方法は、分子レベルでの合成を制御し、所望のナノ構造に構築「ボトムアップ」アプローチです。これは、これらのナノ構造材料1の世代において所望の自己組織化、機能性、受動性、および安定性上のコントロールのかなりの程度を与えます。分子レベルで仕事をすることで、ハイブリッドナノ複合材料は、同じstructu内の両方の材料の利点を提供する生成することができます再。 ナノ材料は、ボトムアップ戦略を介して合成されるように、方法は、粒子サイズ、形状、質感、疎水性、多孔性、電荷、および機能2を制御するために使用される必要があります。金属コアナノ粒子​​合成では、最初の金属塩は、今度は他の粒子の核生成を指示するゼロ価の粒子を生成するために、自己触媒過程で還元されます。これは、クラスタリングにつながり、最終的にナノ粒子の生産3。作成されたナノ粒子のサイズを制御し、溶液から沈殿するのを防止するために、そのようなリガンド、界面活性剤、イオン電荷、大きなポリマーなどの安定剤をさらに凝集4-10からナノ粒子をブロックするそれらの能力のために利用されます。これらの材料は、立体障害による貫通嵩高い基の存在のために、またはクーロン反発3のいずれかによって、ナノ粒子のファンデルワールス力を阻害します。 トンで彼の作品、容易な、ワンポット、シランを用いた各種金属コアナノ粒子の生成のための合成戦略、N-（2-アミノエチル）-3- aminosilanetriol（2- AST）は（ 図1）に提示されています。この化合物の配位子は、金属前駆体を還元し、比較的高い効率を有する金属ナノ粒子を安定化することが可能です。存在する3つのシラノール部分はまた、架橋することができ、これは、マトリックス内のナノ粒子（ 図2）を含浸させたオルガノシランポリマーの相互接続ネットワークを形成します。容易に水の存在下で加水分解を受けるほとんどのシランとは異なり、この化合物は、疎水性のために、安定性、及び制御のために有益である、水中で安定化されます。

<table border="0" cellpadding="0" cellspacing="0" width="644">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:287px;">n-(2-aminoethyl)-3-aminosilanetriol (2-AST)</td>
			<td style="width:209px;">Gelest</td>
			<td style="width:72px;">SIA0590.0</td>
			<td style="width:76px;">25% in H2O</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Silver nitrate</td>
			<td>Sigma Aldrich</td>
			<td>S6506</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Gold(III) chloride trihydrate</td>
			<td>Sigma Aldrich</td>
			<td align="right">520918</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Palladium(II) Nitrate</td>
			<td>Alfa Aesar</td>
			<td align="right">11035</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Deuterium Dioxide</td>
			<td>Cambridge Isotope Laboratories</td>
			<td>DLM-4-100</td>
			<td></td>
		</tr>
	</tbody>
</table>

generation of zerovalent metal core nanoparticles using n-(2-aminoethyl)-3-aminosilanetriol

In this work, a facile one-pot reaction for the formation of metal nanoparticles in a water solution through the use of n-(2-aminoethyl)-3-aminosilanetriol is presented. This compound can be used to effectively reduce and complex metal salts into metal core nanoparticles coated with the compound. By controlling the concentrations of salt and silane one is able to control reaction rates, particle size, and nanoparticle coating. The effects of these changes were characterized through transmission electron microscopy (TEM), UV-Vis spectrometry (UV-Vis), Nuclear Magnetic Resonance spectroscopy (NMR) and Fourier Transform Infrared spectroscopy (FTIR). A unique aspect to this reaction is that usually silanes hydrolyze and cross-link in water; however, in this system the silane is water-soluble and stable. It is known that silicon and amino moieties can form complexes with metal salts. The silicon is known to extend its coordination sphere to form penta- or hexa-coordinated species. Furthermore, the silanol group can undergo hydrolysis to form a Si-O-Si silica network, thereby transforming the metal nanoparticles into a functionalized nanocomposites.

ナノ粒子形成は、個々の金属ナノ粒子のための特徴的なピークを生成しなければならないような反応は、紫外 - 可視分光法を介して監視しました。合成された材料の最終的な分析は、TEMおよびFTIRを介して達成されました。 FTIRスペクトルは、サンプルの乾燥粉末から得られました。粒子サイズ分析は、TEM平均化結果を介して得られた画像から、ナノ粒子の直径を測定?...

Watch this Scientific Journal Video about Generation of Zerovalent Metal Core Nanoparticles Using n-2-aminoethyl-3-aminosilanetriol at JoVE.com

Generation of Zerovalent Metal Core Nanoparticles Using n-2-aminoethyl-3-aminosilanetriol

A novel method for metal core nanoparticle synthesis using a water stable silanol is described.

ゼロ価金属コアのナノ粒子の生成は、N-使用（2-アミノエチル）-3- aminosilanetriol

In this work, a facile one-pot reaction for the formation of metal nanoparticles in a water solution through the use of ...

generation-zerovalent-metal-core-nanoparticles-using-n-2-aminoethyl-3

Research

JoVE Journal

Chemistry

Generation of Zerovalent Metal Core Nanoparticles Using n-(2-aminoethyl)-3-aminosilanetriol

7.6K ビュー.  William Paterson University. A novel method for metal core nanoparticle synthesis using a water stable silanol is described.

ビデオ: Generation of Zerovalent Metal Core Nanoparticles Using n-2-aminoethyl-3-aminosilanetriol

Using Polystyrene-block-poly(acrylic acid)-coated Metal Nanoparticles as Monomers for Their Homo- and Co-polymerization

We present a template-free method for &#8220;polymerizing&#8221; nanoparticles into long chains without side branches. A variety of nanoparticles are encapsulated in polystyrene-block-poly(acrylic acid) (PSPAA) shells and then used as monomers for their self-assembly. Spherical PSPAA micelles upon acid treatment are known to assemble into cylindrical micelles. Exploiting this tendency, the core-shell nanoparticles are induced to aggregate, coalesce, and then transform into long chains. When more than one type of nanoparticles are used, random and block &#8220;copolymers&#8221; of nanoparticles can be obtained. Detailed procedures are reported for the PSPAA encapsulation of nanoparticles, homo- and co-polymerization of the core-shell nanoparticles, separation and purification of the resulting nanoparticle chains. Transformations of single-line chains into double- and triple-line chains are also presented. The synergy between the polymer shell and the embedded nanoparticles leads to an unusual chain-growth polymerization mode, giving long nanoparticle chains that are distinct from the products of the traditional step-growth aggregation process.

Using Polystyrene-block-polyacrylic acid-coated Metal Nanoparticles as Monomers for Their Homo- and Co-polymerization

We report protocols for &#8220;polymerizing&#8221; various types of polymer-encapsulated metal nanoparticles into long chains of &#8220;homo-&#8220; and &#8220;co-polymers&#8221;.

ポリスチレンを使用しました<em&gt;ブロック</em&gt; - ポリ（アクリル酸）は、それらのホモポリマーおよび共重合用単量体として金属ナノ粒子をコーティングを採用

We present a template-free method for &#8220;polymerizing&#8221; nanoparticles into long chains without side branches. A variety of nanoparticles are ...

化学

Reverse Microemulsion-mediated Synthesis of Monometallic and Bimetallic Early Transition Metal Carbide and Nitride Nanoparticles

A reverse microemulsion is used to encapsulate monometallic or bimetallic early transition metal oxide nanoparticles in microporous silica shells. The silica-encapsulated metal oxide nanoparticles are then carburized in a methane/hydrogen atmosphere at temperatures over 800 &#176;C to form silica-encapsulated early transition metal carbide nanoparticles. During the carburization process, the silica shells prevent the sintering of adjacent carbide nanoparticles while also preventing the deposition of excess surface carbon. Alternatively, the silica-encapsulated metal oxide nanoparticles can be nitridized in an ammonia atmosphere at temperatures over 800 &#176;C to form silica-encapsulated early transition metal nitride nanoparticles. By adjusting the reverse microemulsion parameters, the thickness of the silica shells, and the carburization/nitridation conditions, the transition metal carbide or nitride nanoparticles can be tuned to various sizes, compositions, and crystal phases. After carburization or nitridation, the silica shells are then removed using either a room-temperature aqueous ammonium bifluoride solution or a 0.1 to 0.5 M NaOH solution at 40-60 &#176;C. While the silica shells are dissolving, a high surface area support, such as carbon black, can be added to these solutions to obtain supported early transition metal carbide or nitride nanoparticles. If no high surface area support is added, then the nanoparticles can be stored as a nanodispersion or centrifuged to obtain a nanopowder.

A &#8220;removable ceramic coating method&#8221; is presented in visual format for the synthesis of non-sintered and metal-terminated monometallic and bimetallic early transition metal carbide and nitride nanoparticles with tunable sizes and crystal structures.

モノとバイメタル早期遷移金属炭化物と窒化物ナノ粒子の逆マイクロエマルジョン媒介合成

A reverse microemulsion is used to encapsulate monometallic or bimetallic early transition metal oxide nanoparticles in microporous silica shells. The ...

Synthesis, Characterization, and Functionalization of Hybrid Au/CdS and Au/ZnS Core/Shell Nanoparticles

Plasmonic nanoparticles are an attractive material for light harvesting applications due to their easily modified surface, high surface area and large extinction coefficients which can be tuned across the visible spectrum. Research into the plasmonic enhancement of optical transitions has become popular, due to the possibility of altering and in some cases improving photo-absorption or emission properties of nearby chromophores such as molecular dyes or quantum dots. The electric field of the plasmon can couple with the excitation dipole of a chromophore, perturbing the electronic states involved in the transition and leading to increased absorption and emission rates. These enhancements can also be negated at close distances by energy transfer mechanism, making the spatial arrangement of the two species critical. Ultimately, enhancement of light harvesting efficiency in plasmonic solar cells could lead to thinner and, therefore, lower cost devices. The development of hybrid core/shell particles could offer a solution to this issue. The addition of a dielectric spacer between a gold nanoparticles and a chromophore is the proposed method to control the exciton plasmon coupling strength and thereby balance losses with the plasmonic gains. A detailed procedure for the coating of gold nanoparticles with CdS and ZnS semiconductor shells is presented. The nanoparticles show high uniformity with size control in both the core gold particles and shell species allowing for a more accurate investigation into the plasmonic enhancement of external chromophores.

The synthesis of uniform gold nanoparticles coated with semiconductor shells of CdS or ZnS is performed. The semiconductor coating is conducted by first depositing a silver sulfide shell and exchanging the silver cations for zinc or cadmium cations.

合成、キャラクタリゼーション、およびハイブリッドのAu / CdSのとAu / ZnSのコア/シェルナノ粒子の機能化

Plasmonic nanoparticles are an attractive material for light harvesting applications due to their easily modified surface, high surface area and large ...

Sediment Core Extrusion Method at Millimeter Resolution Using a Calibrated, Threaded-rod

Aquatic sediment core subsampling is commonly performed at cm or half-cm resolution. Depending on the sedimentation rate and depositional environment, this resolution provides records at the annual to decadal scale, at best. An extrusion method, using a calibrated, threaded-rod is presented here, which allows for millimeter-scale subsampling of aquatic sediment cores of varying diameters. Millimeter scale subsampling allows for sub-annual to monthly analysis of the sedimentary record, an order of magnitude higher than typical sampling schemes. The extruder consists of a 2 m aluminum frame and base, two core tube clamps, a threaded-rod, and a 1 m piston. The sediment core is placed above the piston and clamped to the frame. An acrylic sampling collar is affixed to the upper 5 cm of the core tube and provides a platform from which to extract sub-samples. The piston is rotated around the threaded-rod at calibrated intervals and gently pushes the sediment out the top of the core tube. The sediment is then isolated into the sampling collar and placed into an appropriate sampling vessel (e.g., jar or bag). This method also preserves the unconsolidated samples (i.e., high pore water content) at the surface, providing a consistent sampling volume. This mm scale extrusion method was applied to cores collected in the northern Gulf of Mexico following the Deepwater Horizon submarine oil release. Evidence suggests that it is necessary to sample at the mm scale to fully characterize events that occur on the monthly time-scale for continental slope sediments.

An extrusion method using a calibrated threaded-rod is presented, which allows for mm scale subsampling of aquatic sediment cores. Millimeter-scale sampling is necessary to fully characterize recent event stratigraphy in sediment records.

キャリブレーション済み、スレッドロッドを用いたミリ解像度での堆積物コアの押出法

Aquatic sediment core subsampling is commonly performed at cm or half-cm resolution. Depending on the sedimentation rate and depositional environment, ...

In Situ Detection and Single Cell Quantification of Metal Oxide Nanoparticles Using Nuclear Microprobe Analysis

Micro-analytical techniques based on chemical element imaging enable the localization and quantification of chemical composition at the cellular level. They offer new possibilities for the characterization of living systems and are particularly appropriate for detecting, localizing and quantifying the presence of metal oxide nanoparticles both in biological specimens and the environment. Indeed, these techniques all meet relevant requirements in terms of (i) sensitivity (from 1 up to 10 &#181;g.g-1 of dry mass), (ii) micrometer range spatial resolution, and (iii) multi-element detection. Given these characteristics, microbeam chemical element imaging can powerfully complement routine imaging techniques such as optical and fluorescence microscopy. This protocol describes how to perform a nuclear microprobe analysis on cultured cells (U2OS) exposed to titanium dioxide nanoparticles. Cells must grow on and be exposed directly in a specially designed sample holder used on the optical microscope and in the nuclear microprobe analysis stages. Plunge-freeze cryogenic fixation of the samples preserves both the cellular organization and the chemical element distribution. Simultaneous nuclear microprobe analysis (scanning transmission ion microscopy, Rutherford backscattering spectrometry and particle induced X-ray emission) performed on the sample provides information about the cellular density, the local distribution of the chemical elements, as well as the cellular content of nanoparticles. There is a growing need for such analytical tools within biology, especially in the emerging context of Nanotoxicology and Nanomedicine for which our comprehension of the interactions between nanoparticles and biological samples must be deepened. In particular, as nuclear microprobe analysis does not require nanoparticles to be labelled, nanoparticle abundances are quantifiable down to the individual cell level in a cell population, independently of their surface state.

In Situ Detection and Single Cell Quantification of Metal Oxide Nanoparticles Using Nuclear Microprobe Analysis

We describe a procedure for the detection of chemical elements present in situ in human cells as well as their in vitro quantification. The method is well-suited to any cell type and is particularly useful for quantitative chemical analyses in single cells following in vitro metal oxide nanoparticles exposure.

その場で検出および核マイクロ プローブ分析法を用いた金属酸化物ナノ粒子の単一細胞定量

Micro-analytical techniques based on chemical element imaging enable the localization and quantification of chemical composition at the cellular level. ...

Determination of Thermodynamic Properties of Alkaline Earth-liquid Metal Alloys Using the Electromotive Force Technique

A novel electrochemical cell based on a CaF2 solid-state electrolyte has been developed to measure the electromotive force (emf) of binary alkaline earth-liquid metal alloys as functions of both composition and temperature in order to acquire thermodynamic data. The cell consists of a chemically stable solid-state CaF2-AF2 electrolyte (where A is the alkaline-earth element such as Ca, Sr, or Ba), with binary A-B alloy (where B is the liquid metal such as Bi or Sb) working electrodes, and a pure A metal reference electrode. Emf data are collected over a temperature range of 723 K to 1,123 K in 25 K increments for multiple alloy compositions per experiment and the results are analyzed to yield activity values, phase transition temperatures, and partial molar entropies/enthalpies for each composition.

This protocol describes the measurement of the electromotive force of alkaline-earth elements in liquid metal alloys at high temperatures (723-1,123 K) to determine their thermodynamic properties, including activity, partial molar entropy, partial molar enthalpy, and phase transition temperatures, over a wide composition range.

起電力法を用いたアルカリ土類液体金属合金の熱力学的性質の測定

A novel electrochemical cell based on a CaF2 solid-state electrolyte has been developed to measure the electromotive force (emf) of binary alkaline ...

Ligand-Mediated Nucleation and Growth of Palladium Metal Nanoparticles

The size, size distribution and stability of colloidal nanoparticles are greatly affected by the presence of capping ligands. Despite the key contribution of capping ligands during the synthesis reaction, their role in regulating the nucleation and growth rates of colloidal nanoparticles is not well understood. In this work, we demonstrate a mechanistic investigation of the role of trioctylphosphine (TOP) in Pd nanoparticles in different solvents (toluene and pyridine) using in situ SAXS and ligand-based kinetic modeling. Our results under different synthetic conditions reveal the overlap of nucleation and growth of Pd nanoparticles during the reaction, which contradicts the LaMer-type nucleation and growth model. The model accounts for the kinetics of Pd-TOP binding for both, the precursor and the particle surface, which is essential to capture the size evolution as well as the concentration of particles in situ. In addition, we illustrate the predictive power of our ligand-based model through designing the synthetic conditions to obtain nanoparticles with desired sizes. The proposed methodology can be applied to other synthesis systems and therefore serves as an effective strategy for predictive synthesis of colloidal nanoparticles.

The main goal of this work is to elucidate the role of capping agents in regulating the size of palladium nanoparticles by combining in situ small angle x-ray scattering (SAXS) and ligand-based kinetic modeling.

リガンドを介した核生成とパラジウムの金属ナノ粒子の成長

The size, size distribution and stability of colloidal nanoparticles are greatly affected by the presence of capping ligands. Despite the key contribution ...

Molten-Salt Synthesis of Complex Metal Oxide Nanoparticles

The development of feasible synthesis methods is critical for the successful exploration of novel properties and potential applications of nanomaterials. Here, we introduce the molten-salt synthesis (MSS) method for making metal oxide nanomaterials. Advantages over other methods include its simplicity, greenness, reliability, scalability, and generalizability. Using pyrochlore lanthanum hafnium oxide (La2Hf2O7) as a representative, we describe the MSS protocol for the successful synthesis of complex metal oxide nanoparticles (NPs). Furthermore, this method has the unique ability to produce NPs with different material features by changing various synthesis parameters such as pH, temperature, duration, and post-annealing. By fine-tuning these parameters, we are able to synthesize highly uniform, non-agglomerated, and highly crystalline NPs. As a specific example, we vary the particle size of the La2Hf2O7&#160;NPs by changing the concentration of the ammonium hydroxide solution used in the MSS process, which allows us to further explore the effect of particle size on various properties. It is expected that the MSS method will become a more popular synthesis method for nanomaterials and more widely employed in the nanoscience and nanotechnology community in the upcoming years.

Here, we demonstrate a unique, relatively low-temperature, molten-salt synthesis method for preparing uniform complex metal oxide lanthanum hafnate nanoparticles.

複合金属酸化物ナノ粒子の溶融塩合成

The development of feasible synthesis methods is critical for the successful exploration of novel properties and potential applications of nanomaterials. ...

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis

Heteroarylation introduces heteroaryl fragments to organic molecules. Despite the numerous available reactions reported for arylation via transition metal catalysis, the literature on direct heteroarylation is scarce. The presence of heteroatoms such as nitrogen, sulfur and oxygen often make heteroarylation a challenging research field due to catalyst poisoning, product decomposition and the rest. This protocol details a highly efficient direct &#945;-C(sp3) heteroarylation of ketones under microwave irradiation. Key factors for successful heteroarylation include the use of XPhos Palladacycle Gen. 4 Catalyst, excess base to suppress side reactions and the high temperature and pressure achieved in a sealed reaction vial under microwave irradiation. The heteroarylation compounds prepared by this method were fully characterized by proton nuclear magnetic resonance spectroscopy (1H NMR), carbon nuclear magnetic resonance spectroscopy (13C NMR) and high-resolution mass spectrometry (HRMS). This methodology has several advantages over literature precedents including broad substrate scope, rapid reaction time, greener procedure and operational simplicity by eliminating the preparation of intermediates such as silyl enol ether. Possible applications for this protocol include, but are not limited to, diversity-oriented synthesis for the discovery of biologically active small molecules, domino synthesis for the preparation of natural products and ligand development for new transition metal catalytic systems.

Heteroaryl compounds are important molecules utilized in organic synthesis, medicinal and biological chemistry. A microwave-assisted heteroarylation using palladium catalysis provides a rapid and efficient method to attach heteroaryl moieties directly to ketone substrates.

遷移金属触媒を用いたケトンのマイクロ波アシスト直接ヘテロリル化

Heteroarylation introduces heteroaryl fragments to organic molecules. Despite the numerous available reactions reported for arylation via transition metal ...

Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)

Substrate size discrimination by the pore size and homogeneity of the chiral environment at the reaction sites are important issues in the validation of the reaction site in metal-organic framework (MOF)&#8211;based catalysts in an enantioselective catalytic reaction system. Therefore, a method of validating the reaction site of MOF-based catalysts is necessary to investigate this issue. Substrate size discrimination by pore size was accomplished by comparing the substrate size versus the reaction rate in two different types of carbonyl-ene reactions with two kinds of MOFs. The MOF catalysts were used to compare the performance of the two reaction types (Zn-mediated stoichiometric and Ti-catalyzed carbonyl-ene reactions) in two different media. Using the proposed method, it was observed that the entire MOF crystal participated in the reaction, and the interior of the crystal pore played an important role in exerting chiral control when the reaction was stoichiometric. Homogeneity of the chiral environment of MOF catalysts was established by the size control method for a particle used in the Zn-mediated stoichiometric reaction system. The protocol proposed for the catalytic reaction revealed that the reaction mainly occurred on the catalyst surface regardless of the substrate size, which reveals the actual reaction sites in MOF-based heterogeneous catalysts. This method for reaction site validation of MOF catalysts suggests various considerations for developing heterogeneous enantioselective MOF catalysts.

Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs

Here, we present a protocol for active site validation of metal-organic framework catalysts by comparing stoichiometric and catalytic carbonyl-ene reactions to find out whether a reaction takes place on the inner or outer surface of metal-organic frameworks.

キラル金属有機フレームワーク(MRF)を用いた不均一なエナンチオ選択的触媒の開発

Substrate size discrimination by the pore size and homogeneity of the chiral environment at the reaction sites are important issues in the validation of ...