Diese Arbeit wurde von National Natur Science Foundation of China (21301104), die grundlegende Forschungsmittel für die zentralen Universitäten (FRF-TP-16-019A3) und der State Key Laboratory of Chemical Engineering (SKL-ChE-14A04) unterstützt.

1. Synthese des Mono-(2,3-Dimethylbutyl) phosphinic Säure 18 , 19 <ol><li>Reaktion <ol><li>wiegen 31,80 g Natrium Natriumhypophosphit Hydrat, 16.00 Uhr g-Essigsäure, 8,42 g 2,3-Dimethyl-1-Buten, 0,73 g di - Tert-Butylnperoxide (DTBP), 25,00 g Tetrahydrofuran (THF) in einem 100 mL Teflon ausgekleidet Edelstahl Autoklaven Autoklaven ein Magnetrührer umgesetzt und versiegeln it.</li>
		<li>Setzen den Autoklaven in eine vertikale Rohrofen, unter denen eine magnetische Stirringapparatus ist. Starten Sie das magnetische rühren Gerät und stellen Sie die Geschwindigkeit bei 800 u/min.</li>
		<li>Stellen das Heizprogramm der Temperaturregler an den Autoklaven angeschlossen: Erhitzen von Raumtemperatur bis 120 ° C während 90 min, bei 120 ° C für 8 h beizubehalten, dann natürlich auf Raumtemperatur abkühlen. Starten Sie das Heizprogramm.</li>
	</ol></li> <li>Nach der Behandlung <ol><li>die Produkte in einem 250 mL 1-Hals Rundboden Kolben übertragen, waschen die Teflon-Auskleidung mit 50 mL THF und fügen Sie es in der gleichen Flasche um sicherzustellen, dass alle Produkte übertragen werden.</li>
		<li>Entfernen Sie die THF und nicht umgesetztes Olefine mit einem Drehverdampfer.</li>
		<li>Transfer Essigreiniger in einem 250 mL Trichter zu trennen, bzw. die Flasche mit 30 mL entionisiertem Wasser und 80 mL Ethylether waschen und fügen Sie sie in der gleichen Scheidetrichter um sicherzustellen, dass alle Produkte übertragen werden.</li>
		<li>Fügen Sie 50 mL 4 % NaOH Lösung in den oben genannten Scheidetrichter, schütteln Sie sie kräftig und die wässrige Phase zu trennen. Die organische Phase mit 20 mL 4 % NaOH Lösungen für dreimal zu extrahieren (20 mL × 3) um sicherzustellen, dass die wässrige Phase pH 10 übersteigt.</li>
		<li>Der wässrigen Lösungen im obigen Schritt kombinieren, und übertragen Sie sie in einen 500 mL Trichter trennen.</li>
		<li>Fügen Sie 90 mL 10 % H 2 SO 4 Lösung 50 mL Ethylether, kräftig schütteln und trennen die organische Phase; dann extrahieren die wässrige Phase mit 30 mL Ethylether dreimal (30 mL × 3).</li>
		<li>Kombinieren die Ethylether Lösungen im Schritt 1.2.6, und übertragen Sie sie in eine andere 500 mL Trichter trennen.</li>
		<li>Waschen Sie es mit 100 mL gesättigte NaCl-Lösungen vier Zeiten (100 mL × 4).</li>
		<li>Fügen Sie 4 g wasserfreies MgSO 4, lösliche Wasser zu entfernen. Filtern, um den Volumenkörper zu entfernen, und sammeln Sie die Flüssigkeit in einem sauberen 250 mL 1-Hals Rundboden Kolben.</li>
		<li>Entfernen Sie die Nutzung der Drehverdampfer 17,92 g das Rohprodukt Ethylether.</li>
	</ol></li></ol> 2. Reinigung des Mono-(2,3-Dimethylbutyl) phosphinic Säure <ol><li>Vorbereitung von Amantadin Lösung <ol><li>22,28 g von Amantadin-Hydrochlorid in 100 mL entionisiertem Wasser in einen 500-mL-Becherglas auflösen.</li>
		<li>Hinzufügen 100 mL gesättigte NaOH Lösung und unter Rühren 5 min.</li>
		<li>150 mL Ethylether hinzugeben und rühren, bis die weiße Niederschlag in Schritt 2.1.2 generierten verschwindet.</li>
		<li>Übertragen die Lösungen in einem 500 mL Trichter zu trennen, das Becherglas mit Ethylether dreimal waschen (50 mL × 3), und kombinieren sie in der gleichen Scheidetrichter.</li>
		<li>Die wässrige Phase zu trennen, und waschen Sie die organische Phase mit gesättigte NaCl-Lösungen fünf Mal (100 mL × 5).</li>
		<li>Fügen Sie 4 g wasserfreies MgSO 4, lösliche Wasser zu entfernen. Filter, Amantadin Ethylether Lösung zu erhalten.</li>
	</ol></li> <li>Vorbereitung von Amantadin &#8729; Mono-(2,3-Dimethylbutyl) phosphinic Säure Salz <ol><li>die Amantadin-Lösung tropfenweise das Rohöl Mono-(2,3-Dimethylbutyl) phosphinic Säure Produkt hinzufügen. Während Drop hinzufügen 150 mL Ethylether um sicherzustellen, dass es richtig rühren kann.</li>
		<li>Waschen die eins-Hals Rundboden Küvette mit dem Mono-(2,3-Dimethylbutyl) phosphinic Säure Produkt mit 50 mL Ethylether um sicherzustellen, dass das Produkt auf die Amantadin Lösung übertragen wird. 30 min. köcheln, und lassen Sie es über Nacht.</li>
		<li>Filter unter vermindertem Druck, und waschen Sie den Filterkuchen mit 200 mL Ethylether.</li>
	</ol></li> <li>Lassen Sie die Mono-(2,3-Dimethylbutyl) phosphinic Säure <ol><li>übertragen die gefilterte Kuchen in einen 500-mL-Becherglas, 80 mL 1 M HCl zugeben und 5 min. köcheln</li>
		<li>Fügen Sie 70 mL Ethylacetat, und rühren Sie für eine weitere 5 min.</li>
		<li>Übertragen die Lösungen in einem 250 mL Trichter zu trennen und die wässrige Phase zu trennen.</li>
		<li>Die wässrige Phase mit 40 mL Ethylacetat wieder extrahieren und Ethylacetat Lösungen zu kombinieren.</li>
		<li>Der Ethylacetat Waschlösung mit 30 mL 1 M HCl zweimal (30 mL × 2) und gesättigte NaCl drei Zeiten (80 mL × 3) gegenüber dem Vorquartal.</li>
		<li>Add 4 g wasserfreies MgSO 4, lösliche Wasser zu entfernen. Filtern und sammeln Sie die Flüssigkeit in einem 250 mL 1-Hals Rundboden Kolben.</li>
		<li>Entfernen Sie die Verwendung der Drehverdampfer Ethylacetat und erhalten 12,45 g der reinen Mono-(2,3-Dimethylbutyl) phosphinic Säure (Ertrag: 82,9 %).</li>
	</ol></li></ol> 3. Synthese von (2,3-Dimethylbutyl) (2,4,4 &#39;-Trimethylpentyl) phosphinic Säure <ol><li>Reaktion <ol><li>Transfer alle von der reinen Mono-(2,3-Dimethylbutyl) phosphinic Säure Produkt in 100 mL Teflon ausgekleidet Edelstahl Autoklaven, 4,95 g Essigsäure, 25,39 g Diisobutylene, 0,30 g DTBP, ein Magnetrührer in den Autoklaven gelegt, und versiegeln it.</li>
		<li>Setzen den Autoklaven in eine vertikale Rohrofen unter denen ist ein magnetisches rühren Apparat, und starten Sie die magnetische rühren Apparat.</li>
		<li>Stellen das Heizprogramm des Temperaturreglers: Erhitzen von Raumtemperatur bis 135 ° C während 90 min, bei 135 ° C für 8 h beizubehalten, dann natürlich auf Raumtemperatur abkühlen. Starten Sie das Heizprogramm.</li>
		<li>Wenn das Reaktionssystem auf Raumtemperatur abkühlt, fügen Sie ein weiteres 0,30 g DTBP, und starten Sie das Heizprogramm.</li>
		<li>Wiederholen Sie Schritt 3.1.4 einmal.</li>
	</ol></li> <li>Nach der Behandlung <ol><li>verdünnen das Produkt mit 100 mL Ethylether, und übertragen Sie dann auf eine 250 mL Trichter trennen.</li>
		<li>Waschen Sie ihn mit 30 mL 4 % NaOH drei Mal (30 mL × 3) um sicherzustellen, dass wässrige Phase übersteigt pH 10.</li>
		<li>Fügen Sie 70 mL 10 % H 2 SO 4-Lösung für das Produkt ansäuern.</li>
		<li>Waschen Sie ihn mit gesättigte NaCl-Lösung mehrere Male (80 mL) bis der wässrigen Phase pH pH-Wert 6-7 entspricht.</li>
		<li>Fügen Sie 4 g wasserfreies MgSO 4, lösliche Wasser zu entfernen. Filtern, um den Volumenkörper zu entfernen, und sammeln Sie die Flüssigkeit in einem sauberen 250 mL 1-Hals Rundboden Kolben.</li>
		<li>Entfernen Sie die Ethylether und nicht umgesetztes Olefine mit der Drehverdampfer 15,10 g Rohprodukt erhalten.</li>
	</ol></li></ol> 4. Reinigung von (2,3-Dimethylbutyl) (2,4,4 &#39;-Trimethylpentyl) phosphinic Säure <ol><li>reine co-(2,3-dimethylbutyl) zu erhalten (2,4,4 &#39;-Trimethylpentyl) phosphinic Säure Komplex <ol><li>auflösen 2,30 g NaOH in 40 mL deionisiertes Wasser. Fügen Sie die NaOH-Lösung in den Kolben mit dem Rohöl (2,3-Dimethylbutyl) (2,4,4 &#39;-Trimethylpentyl) phosphinic Säure Produkt, und schütteln Sie sie kräftig für 5 min.</li>
		<li>Add 0,5 M CoCl 2 Lösung tropfenweise unter schütteln, bis keine weiteren blauen Niederschlag entsteht und die Lösung in der Flasche rosa ist. < Li> <li>Filter und Waschen der blauen Niederschlag mit entionisiertem Wasser bis der Filterkuchen ist farblos.</li>
		<li>Transfer den Filterkuchen in ein 250-mL-Becherglas, geben Sie 100 mL Aceton mit konservierenden Film versiegeln und kühlen Sie es bei 4 ° C für eine Nacht.</li>
		<li>Pulverisieren der blauen Niederschlag Verunreinigungen freizugebende in der Masse gefangen.</li>
		<li>Filter und waschen Sie es mit 100 mL frischem Aceton. Den Filterkuchen bei Raumtemperatur zu trocknen, und übertragen Sie es dann in einem 250 mL Trichter trennen.</li>
	</ol></li> <li>Regenerieren die (2,3-Dimethylbutyl) (2,4,4 &#39;-Trimethylpentyl) phosphinic Säure <ol><li>120 mL Ethylether und 80 mL 10 % H 2 hinzufügen, so dass 4 und schütteln Sie kräftig bis der blauen Niederschlag verschwindet.</li>
		<li>Die wässrige Phase zu trennen, waschen Sie die organische phase gegenüber dem Vorquartal mit 30 mL 10 % H 2 SO 4 Mal und gesättigte NaCl-Lösungen mehrmals (80 mL), bis der pH-Wert der wässrigen Phase pH 6-7 entspricht.</li>
		<li>Fügen Sie 4 g wasserfreies MgSO 4, lösliche Wasser zu entfernen. Filter zum Entfernen des Volumenkörpers und sammeln Sie die Flüssigkeit in einem sauberen 250 mL 1-Hals Rundboden Kolben.</li>
		<li>Entfernen Sie die Verwendung der Drehverdampfer Ethylether, und erhalten 11,46 g reines Produkt (Ertrag: 52,8 %).</li>
	</ol>
	</li>
</ol>

<ol>
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Die wichtigste Schritt im Rahmen des Protokolls ist die Mono-Alkylphosphinic Säure Synthese (Abbildung 1(ein). In dieser Reaktion ist einen höheren Ertrag und weniger Dialkylphosphinic Säure Nebenprodukt besser. Erhöht das molare Verhältnis von NaH2PO2/olefin A verbessert die Ausbeute und hemmen die Generation der Dialkylphosphinic Säure Nebenprodukt. Allerdings wird eine große NaH2PO2 Dosis auch erhöhen die Kosten und eine...

Sauren Organophosphor Extraktionsmittel sind im traditionellen Hydrometallurgie Bereich für Extraktion und Trennung der seltenen Erden Ionen1,2, Nichteisen-Metalle (wie Co/Ni3,4), seltene Metalle (weit verbreitet z. B. Hf/Zr5, V6,7) Actiniden8, etc.. In den letzten Jahren haben sie auch mehr Aufmerksamkeit im Bereich der sekundären Ressourcenrecycling und hochrangige flüssigen Abfallbeseitigung9angezogen. -(2-Ethylhexyl) Phosphorsäure (D2EHPA oder P204), 2-Ethylhexylphosphoric Säure Mono-2-Ethylhexyl Ester (EHEHPA, PC 88A oder P507) und Di - di (2,4, 4'-Trimethylpentyl)-phosphinic Säure (Cyanex272), die Vertreter der Dialkylphosphoric Säuren, Alkylphosphoric Säure Mono-Alkyl-Ester und Dialkylphosphinic Säuren sind jeweils die am häufigsten verwendeten Extraktionsmittel. Ihre Säure sinkt in der folgenden Reihenfolge: P204 &#62; P507 &#62; Cyanex 272. Die entsprechenden Extraktion Fähigkeit, Absaugleistung und stripping Säure sind alle in der Größenordnung von P204 &#62; P507 &#62; Cyanex 272 und die Trennleistung ist in umgekehrter Reihenfolge. Diese drei Extraktionsmittel sind in den meisten Fällen wirksam. Es gibt jedoch noch einige Bedingungen sie nicht so effizient sind: bei schweren seltenen Erden Trennung, von denen die bestehenden Hauptprobleme die Armen Selektivität und stripping Übersäuerung P204 und P507 sind, niedrige Saugleistung und Emulsion Tendenz während der Extraktion für Cyanex 272. So hat die Entwicklung von neuartigen Extraktionsmittel in den letzten Jahren größere hingewiesen.
Die Klasse der Dialkylphosphinic Säure Extraktionsmittel gilt als einer der wichtigsten Forschungsaspekte neue Extraktionsmittel zu entwickeln. Neuere Forschungen zeigten, dass die Fähigkeit der Extraktion von Dialkylphosphinic Säuren weitgehend von der Struktur der Alkyl Substituenten10,11 hängt. Es kann eine breite Palette von erheblich höher als die der P507, niedriger als der Cyanex 27212sein. Jedoch beschränkt sich die Erforschung des neuartigen Dialkylphosphinic Säure Extraktionsmittel zur kommerziellen Olefin Struktur10,12,13,14,15, 16. Obwohl Dialkylphosphinic Säure Extraktionsmittel durch die Grignard-Reaktion-Methode auch synthetisiert werden kann, sind die Reaktionsbedingungen strenge12,17.
NSDAPA, von denen die zwei Alkyls unterscheiden, öffnet sich eine Tür für die Erforschung von neuen Extraktionsmittel. Es macht die Strukturen der Dialkylphosphinic Säure vielfältiger, und seine Extraktion und Trennung Leistung kann durch eine Änderung beider seiner Alkyl-Strukturen angepasst. Die traditionelle synthetische Methode der NSDAPA verwendet PH3 als eine Phosphor-Quelle, die hat viele Nachteile wie hohe Toxizität, strengen Reaktionsbedingungen und schwierige Reinigung. Vor kurzem berichteten wir über eine neue Methode zur Synthese von NSDAPA mit Natrium Natriumhypophosphit als eine Phosphor Quelle (siehe Abbildung 1) und drei NSDAPAs18erfolgreich synthetisiert. Dieses ausführliche Protokoll kann helfen, neue Praktiker die Experimente zu wiederholen und die synthetische Methode der NSDAPA Extraktionsmittel zu meistern. Wir nehmen (2,3-Dimethylbutyl) (2,4, 4'-Trimethylpentyl) phosphinic Säure als Vorbild. Die Namen und Strukturen der Olefin A, die Mono-Alkylphosphinic Säure zwischen-, Olefin B und die entsprechenden NSDAPA sind in Tabelle 1dargestellt.

<table><tbody><tr><td>2,3-dimethyl-1-butene</td><td>Adamas Reagent Co., Ltd.</td><td></td><td>Molecular formula: C&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;6&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;H&lt;/span&gt;&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;12&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;, purity &amp;ge;99%&lt;/span&gt;</td></tr><tr><td>diisobutylene</td><td>Shanghai&amp;nbsp;Aladdin&amp;nbsp;Bio-Chem&amp;nbsp;Technology&amp;nbsp;Co.,&amp;nbsp;LTD</td><td></td><td>Molecular formula: C&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;8&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;H&lt;/span&gt;&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;16&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;, purity 97%&lt;/span&gt;</td></tr><tr><td>acetic acid</td><td>Sinopharm Chemical Reagent Co., Ltd.</td><td></td><td>Molecular formula: C&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;H&lt;/span&gt;&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;4&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;O&lt;/span&gt;&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;, purity &amp;ge;99.5%&lt;/span&gt;</td></tr><tr><td>di-&lt;span class=&quot;font9&quot;&gt;tert&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;-butylnperoxide&lt;/span&gt;</td><td>Sinopharm Chemical Reagent Co., Ltd.</td><td></td><td>Molecular formula: C&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;8&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;H&lt;/span&gt;&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;18&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;O&lt;/span&gt;&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;, purity &amp;ge;97.0%&lt;/span&gt;</td></tr><tr><td>tetrahydrofuran</td><td>Beijing Chemical Works</td><td></td><td>Molecular formula: C&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;4&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;H&lt;/span&gt;&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;8&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;O, purity A.R.&lt;/span&gt;</td></tr><tr><td>ethyl ether</td><td>Sinopharm Chemical Reagent Co., Ltd.</td><td></td><td>Molecular formula: C&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;4&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;H&lt;/span&gt;&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;10&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;O, purity &amp;ge;99.7%&lt;/span&gt;</td></tr><tr><td>ethyl acetate</td><td>Xilong Chemical Co., Ltd.</td><td></td><td>Molecular formula: C&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;4&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;H&lt;/span&gt;&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;8&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;O&lt;/span&gt;&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;, purity &amp;ge;99.5%&lt;/span&gt;</td></tr><tr><td>acetone</td><td>Beijing Chemical Works</td><td></td><td>Molecular formula: C&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;3&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;H&lt;/span&gt;&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;6&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;O, purity &amp;ge;99.5%&lt;/span&gt;</td></tr><tr><td>sodium hydroxide</td><td>Xilong Chemical Co., Ltd.</td><td></td><td>Molecular formula: NaOH, purity &amp;ge;96.0%</td></tr><tr><td>concentrated sulfuric acid</td><td>Sinopharm Chemical Reagent Co., Ltd.</td><td></td><td>Molecular formula: H&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;SO&lt;/span&gt;&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;4&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;, purity 95-98%&lt;/span&gt;</td></tr><tr><td>hydrochloric acid</td><td>Beijing Chemical Works</td><td></td><td>Molecular formula: HCl, purity 36-38%</td></tr><tr><td>sodium chloride</td><td>Sinopharm Chemical Reagent Co., Ltd.</td><td></td><td>Molecular formula: NaCl, purity &amp;ge;99.5%</td></tr><tr><td>anhydrous magnesium sulfate</td><td>Tianjin Jinke Institute of Fine Chemical Industry</td><td></td><td>Molecular formula: MgSO&lt;span class=&quot;font8&quot;&gt;&lt;sub&gt;4&lt;/sub&gt;&lt;/span&gt;&lt;span class=&quot;font7&quot;&gt;, purity &amp;ge;99.0%&lt;/span&gt;</td></tr></tbody></table>

synthesis of high purity nonsymmetric dialkylphosphinic acid extractants

Wir präsentieren die Synthese von (2,3-Dimethylbutyl) (2,4, 4'-Trimethylpentyl) phosphinic Säure als Beispiel für eine Methode zur Synthese von hoher Reinheit beim Dialkylphosphinic Säure Extraktionsmittel zu demonstrieren. Giftige natriumarme Natriumhypophosphit wurde die Phosphor-Quelle mit Olefin reagieren ein (2,3-Dimethyl-1-Buten) erzeugen eine Monoalkylphosphinic Säure Mittelstufe gewählt. Amantadin wurde angenommen, um die Dialkylphosphinic Säure Nebenprodukt zu entfernen, da nur die Monoalkylphosphinic Säure reagieren kann, mit Amantadin, eine Amantadine∙mono-Alkylphosphinic saures Salz, zu bilden, während die Dialkylphosphinic Säure mit Amantadin darauf reagieren können seine große sterische Behinderung. Die gereinigten Monoalkylphosphinic Säure wurde mit Olefin B (Diisobutylene) beim Dialkylphosphinic Säure (NSDAPA) liefern dann reagiert. Die nicht umgesetztes Monoalkylphosphinic Säure kann leicht entfernt werden, durch eine einfache Säure-Base-Nachbehandlung und andere organische Verunreinigungen können durch die Ausfällung von Kobalt Salz aussortiert werden. Die Struktur der (2,3-Dimethylbutyl) (2,4, 4'-Trimethylpentyl) phosphinic Säure wurde bestätigt durch NMR 31P, 1H NMR, ESI-MS und FT-IR Die Reinheit wurde durch eine potentiometrische Titration-Methode bestimmt, und die Ergebnisse deuten darauf hin, dass die Reinheit 96 % überschreiten kann.

31 P-NMR-Spektren wurden für die Mono-(2,3-Dimethylbutyl) phosphinic Säure vor und nach der Reinigung von Amantadin-Methode (Abbildung 1a-b) gesammelt. 31 P-NMR-Spektren, 1H NMR-Spektren, MS-Spektren und FT-IR-Spektren wurden für gesammelt (2,3-Dimethylbutyl) (2,4, 4'-Trimethylpentyl) phosphinic Säure (siehe Abbildung 3, Abbildung 4, <strong class...

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Synthesis of High Purity Nonsymmetric Dialkylphosphinic Acid Extractants

Synthese von hoher Reinheit beim Dialkylphosphinic Säure Extraktionsmittel

Ein Protokoll für die Synthese von hoher Reinheit beim Dialkylphosphinic Säure Extraktionsmittel wird präsentiert, wobei (2,3-Dimethylbutyl) (2,4, 4'-Trimethylpentyl) phosphinic Säure als Vorbild.

We present the synthesis of (2,3-dimethylbutyl)(2,4,4&#39;-trimethylpentyl)phosphinic acid as an example to demonstrate a method for the synthesis of high ...

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Acid-base and Solubility Equilibria

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7.4K Aufrufe.  University of Science and Technology Beijing. Ein Protokoll für die Synthese von hoher Reinheit beim Dialkylphosphinic Säure Extraktionsmittel wird präsentiert, wobei (2,3-Dimethylbutyl) (2,4, 4'-Trimethylpentyl) phosphinic Säure als Vorbild.

Serie: Synthesis of High Purity Nonsymmetric Dialkylphosphinic Acid Extractants

Compact Quantum Dots for Single-molecule Imaging

Single-molecule imaging is an important tool for understanding the mechanisms of biomolecular function and for visualizing the spatial and temporal heterogeneity of molecular behaviors that underlie cellular biology 1-4. To image an individual molecule of interest, it is typically conjugated to a fluorescent tag (dye, protein, bead, or quantum dot) and observed with epifluorescence or total internal reflection fluorescence (TIRF) microscopy. While dyes and fluorescent proteins have been the mainstay of fluorescence imaging for decades, their fluorescence is unstable under high photon fluxes necessary to observe individual molecules, yielding only a few seconds of observation before complete loss of signal. Latex beads and dye-labeled beads provide improved signal stability but at the expense of drastically larger hydrodynamic size, which can deleteriously alter the diffusion and behavior of the molecule under study.
Quantum dots (QDs) offer a balance between these two problematic regimes. These nanoparticles are composed of semiconductor materials and can be engineered with a hydrodynamically compact size with exceptional resistance to photodegradation 5. Thus in recent years QDs have been instrumental in enabling long-term observation of complex macromolecular behavior on the single molecule level. However these particles have still been found to exhibit impaired diffusion in crowded molecular environments such as the cellular cytoplasm and the neuronal synaptic cleft, where their sizes are still too large 4,6,7.
Recently we have engineered the cores and surface coatings of QDs for minimized hydrodynamic size, while balancing offsets to colloidal stability, photostability, brightness, and nonspecific binding that have hindered the utility of compact QDs in the past 8,9. The goal of this article is to demonstrate the synthesis, modification, and characterization of these optimized nanocrystals, composed of an alloyed HgxCd1-xSe core coated with an insulating CdyZn1-yS shell, further coated with a multidentate polymer ligand modified with short polyethylene glycol (PEG) chains (Figure 1). Compared with conventional CdSe nanocrystals, HgxCd1-xSe alloys offer greater quantum yields of fluorescence, fluorescence at red and near-infrared wavelengths for enhanced signal-to-noise in cells, and excitation at non-cytotoxic visible wavelengths. Multidentate polymer coatings bind to the nanocrystal surface in a closed and flat conformation to minimize hydrodynamic size, and PEG neutralizes the surface charge to minimize nonspecific binding to cells and biomolecules. The end result is a brightly fluorescent nanocrystal with emission between 550-800 nm and a total hydrodynamic size near 12 nm. This is in the same size range as many soluble globular proteins in cells, and substantially smaller than conventional PEGylated QDs (25-35 nm).

We describe the preparation of colloidal quantum dots with minimized hydrodynamic size for single-molecule fluorescence imaging. Compared to conventional quantum dots, these nanoparticles are similar in size to globular proteins and are optimized for single-molecule brightness, stability against photodegradation, and resistance to nonspecific binding to proteins and cells.

Compact Quantum Dots für Einzelmolekül-Imaging

Single-molecule imaging is an important tool for  understanding the mechanisms of biomolecular function and for visualizing the  spatial and temporal ...

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Synthesis and Purification of Iodoaziridines Involving Quantitative Selection of the Optimal Stationary Phase for Chromatography

The highly diastereoselective preparation of cis-N-Ts-iodoaziridines through reaction of diiodomethyllithium with N-Ts aldimines is described. Diiodomethyllithium is prepared by the deprotonation of diiodomethane with LiHMDS, in a THF/diethyl ether mixture, at -78 &#176;C in the dark. These conditions are essential for the stability of the LiCHI2 reagent generated. The subsequent dropwise addition of N-Ts aldimines to the preformed diiodomethyllithium solution affords an amino-diiodide intermediate, which is not isolated. Rapid warming of the reaction mixture to 0 &#176;C promotes cyclization to afford iodoaziridines with exclusive cis-diastereoselectivity. The addition and cyclization stages of the reaction are mediated in one reaction flask by careful temperature control.
Due to the sensitivity of the iodoaziridines to purification, assessment of suitable methods of purification is required. A protocol to assess the stability of sensitive compounds to stationary phases for column chromatography is described. This method is suitable to apply to new iodoaziridines, or other potentially sensitive novel compounds. Consequently this method may find application in range of synthetic projects. The procedure involves firstly the assessment of the reaction yield, prior to purification, by 1H NMR spectroscopy with comparison to an internal standard. Portions of impure product mixture are then exposed to slurries of various stationary phases appropriate for chromatography, in a solvent system suitable as the eluent in flash chromatography. After stirring for 30 min to mimic chromatography, followed by filtering, the samples are analyzed by 1H NMR spectroscopy. Calculated yields for each stationary phase are then compared to that initially obtained from the crude reaction mixture. The results obtained provide a quantitative assessment of the stability of the compound to the different stationary phases; hence the optimal can be selected. The choice of basic alumina, modified to activity IV, as a suitable stationary phase has allowed isolation of certain iodoaziridines in excellent yield and purity.

A protocol for the diastereoselective one-pot preparation of cis-N-Ts-iodoaziridines is described. The generation of diiodomethyllithium, addition to N-Ts aldimines and cyclization of the amino gem-diiodide intermediate to iodoaziridines is demonstrated. Also included is a protocol to rapidly and quantitatively assess the most appropriate stationary phase for purification by chromatography.

Synthese und Reinigung von Iodoaziridines Einbeziehung Quantitative Auswahl der optimalen stationären Phase für die Chromatographie

The highly diastereoselective preparation of cis-N-Ts-iodoaziridines through reaction of diiodomethyllithium with N-Ts aldimines is described. ...

Chemie

Preparation of Highly Porous Coordination Polymer Coatings on Macroporous Polymer Monoliths for Enhanced Enrichment of Phosphopeptides

We describe a protocol for the preparation of hybrid materials based on highly porous coordination polymer coatings on the internal surface of macroporous polymer monoliths. The developed approach is based on the preparation of a macroporous polymer containing carboxylic acid functional groups and the subsequent step-by-step solution-based controlled growth of a layer of a porous coordination polymer on the surface of the pores of the polymer monolith. The prepared metal-organic polymer hybrid has a high specific micropore surface area. The amount of iron(III) sites is enhanced through metal-organic coordination on the surface of the pores of the functional polymer support. The increase of metal sites is related to the number of iterations of the coating process.
The developed preparation scheme is easily adapted to a capillary column format. The functional porous polymer is prepared as a self-contained single-block porous monolith within the capillary, yielding a flow-through separation device with excellent flow permeability and modest back-pressure. The metal-organic polymer hybrid column showed excellent performance for the enrichment of phosphopeptides from digested proteins and their subsequent detection using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The presented experimental protocol is highly versatile, and can be easily implemented to different organic polymer supports and coatings with a plethora of porous coordination polymers and metal-organic frameworks for multiple purification and/or separation applications.

A procedure for the preparation of porous hybrid separation media composed of a macroporous polymer monolith internally coated by a high surface area microporous coordination polymer is presented.

Vorbereitung hoch poröser Koordinationspolymerbeschichtungen auf makroporösen Monoliths für verbesserte Anreicherung von Phosphopeptiden

We describe a protocol for the preparation of hybrid materials based on highly porous coordination polymer coatings on the internal surface of macroporous ...

Extraction and Characterization of Surfactants from Atmospheric Aerosols

Surface-active compounds, or surfactants, present in atmospheric aerosols are expected to play important roles in the formation of liquid water clouds in the Earth&#39;s atmosphere, a central process in meteorology, hydrology, and for the climate system. But because specific extraction and characterization of these compounds have been lacking for decades, very little is known on their identity, properties, mode of action and origins, thus preventing the full understanding of cloud formation and its potential links with the Earth&#39;s ecosystems.
In this paper we present recently developed methods for 1) the targeted extraction of all the surfactants from atmospheric aerosol samples and for the determination of 2) their absolute concentrations in the aerosol phase and 3) their static surface tension curves in water, including their Critical Micelle Concentration (CMC). These methods have been validated with 9 references surfactants, including anionic, cationic and non-ionic ones. Examples of results are presented for surfactants found in fine aerosol particles (diameter &#60;1 &#956;m) collected at a coastal site in Croatia and suggestions for future improvements and other characterizations than those presented are discussed.

Methods are presented for the targeted extraction of surfactants present in atmospheric aerosols and the determination of their absolute concentrations and surface tension curves in water, including their Critical Micelle Concentration (CMC).

Die Extraktion und Charakterisierung von Tensiden aus Atmosphärische Aerosole

Surface-active compounds, or surfactants, present in atmospheric aerosols are expected to play important roles in the formation of liquid water clouds in ...

Umwelt

Facile Protocol for the Synthesis of Self-assembling Polyamine-based Peptide Amphiphiles (PPAs) and Related Biomaterials

Polyamine-based Peptide Amphiphiles (PPAs) are a new class of self-assembling amphiphilic biomaterials-related to the peptide amphiphiles (PAs). Traditional PAs possess charged amino acids as solubilizing groups (lysine, arginine), which are directly connected to a lipid segment or can contain a linker region made of neutral amino acids. Tuning the peptide sequence of PAs can yield diverse morphologies. Similarly, PPAs possess a hydrophobic segment and neutral amino acids, but also contain polyamine molecules as water solubilizing (hydrophilic) groups. As is the case with PAs, PPAs can also self-assemble into diverse morphologies, including small rods, twisted nano-ribbons, and fused nano-sheets, when dissolved in water. However, the presence of both primary and secondary amines on a single polyamine molecule poses a significant challenge when synthesizing PPAs. In this paper, we show a simple protocol, based on literature precedents, to achieve a facile synthesis of PPAs using solid phase peptide synthesis (SPPS). This protocol can be extended to the synthesis of PAs and other similar systems. We also illustrate the steps that are needed for cleavage from the resin, identification, and purification.

Facile Protocol for the Synthesis of Self-assembling Polyamine-based Peptide Amphiphiles PPAs and Related Biomaterials

The synthesis of polyamine-based peptide amphiphiles (PPAs) is a significant challenge due to the presence of multiple amine nitrogens, which requires judicious use of protecting groups to mask these reactive functionalities. In this paper, we describe a facile method for the preparation of these new class of self-assembling molecules.

Facile Protokoll für die Synthese von selbst zusammenbauen Polyamin-basierte Peptid Amphiphilen (PPA) und der damit verbundenen Biomaterialien

Polyamine-based Peptide Amphiphiles (PPAs) are a new class of self-assembling amphiphilic biomaterials-related to the peptide amphiphiles (PAs). ...

Synthesis of Esters Via a Greener Steglich Esterification in Acetonitrile

The Steglich esterification is a widely-used reaction for the synthesis of esters from carboxylic acids and alcohols. While efficient and mild, the reaction is commonly performed using chlorinated or amide solvent systems, which are hazardous to human health and the environment. Our methodology utilizes acetonitrile as a greener and less hazardous solvent system. This protocol exhibits rates and yields that are comparable to traditional solvent systems and employs an extraction and wash sequence that eliminates the need for the purification of the ester product via column chromatography. This general method can be used to couple a variety of carboxylic acids with 1&#176; and 2&#176; aliphatic alcohols, benzylic and allylic alcohols, and phenols to obtain pure esters in high yields. The goal of the protocol detailed here is to provide a greener alternative to a common esterification reaction, which could serve useful for ester synthesis in both academic and industrial applications.

A modified Steglich esterification reaction was used to synthesize a small library of ester derivatives with primary and secondary alcohols. The methodology uses a non-halogenated and greener solvent, acetonitrile, and enables product isolation in high yields without the need for chromatographic purification.

Synthese von Estern über ein grüner Steglich-Veresterung in Acetonitril

The Steglich esterification is a widely-used reaction for the synthesis of esters from carboxylic acids and alcohols. While efficient and mild, the ...

Preparation of Poly(pentafluorophenyl acrylate) Functionalized SiO2 Beads for Protein Purification

We demonstrate a simple method to prepare poly(pentafluorophenyl acrylate) (poly(PFPA)) grafted silica beads for antibody immobilization and subsequent immunoprecipitation (IP) application. The poly(PFPA) grafted surface is prepared via a simple two-step process. In the first step, 3-aminopropyltrimethoxysilane (APTMS) is deposited as a linker molecule onto the silica surface. In the second step, poly(PFPA) homopolymer, synthesized via the reversible addition and fragmentation chain transfer (RAFT) polymerization, is grafted to the linker molecule through the exchange reaction between the pentafluorophenyl (PFP) units on the polymer and the amine groups on APTMS. The deposition of APTMS and poly(PFPA) on the silica particles are confirmed by X-ray photoelectron spectroscopy (XPS), as well as monitored by the particle size change measured via dynamic light scattering (DLS). To improve the surface hydrophilicity of the beads, partial substitution of poly(PFPA) with amine-functionalized poly(ethylene glycol) (amino-PEG) is also performed. The PEG-substituted poly(PFPA) grafted silica beads are then immobilized with antibodies for IP application. For demonstration, an antibody against protein kinase RNA-activated (PKR) is employed, and IP efficiency is determined by Western blotting. The analysis results show that the antibody immobilized beads can indeed be used to enrich PKR while non-specific protein interactions are minimal.

Preparation of Polypentafluorophenyl acrylate Functionalized SiO2 Beads for Protein Purification

A protocol for the preparation of poly(pentafluorophenyl acrylate) (poly(PFPA)) grafted silica beads is presented. The poly(PFPA) functionalized surface is then immobilized with antibodies and used successfully for the protein separation through immunoprecipitation.

Vorbereitung der Poly(pentafluorophenyl acrylate) funktionalisiert SiO2 Perlen Proteinreinigung

We demonstrate a simple method to prepare poly(pentafluorophenyl acrylate) (poly(PFPA)) grafted silica beads for antibody immobilization and subsequent ...

Enzymatic Synthesis of Epoxidized Metabolites of Docosahexaenoic, Eicosapentaenoic, and Arachidonic Acids

The epoxidized metabolites of various polyunsaturated fatty acids (PUFAs), termed epoxy fatty acids, have a wide range of roles in human physiology. These metabolites are produced endogenously by the cytochrome P450 class of enzymes. Because of their diverse and potent biological effects, there is considerable interest in studying these metabolites. Determining the unique roles of these metabolites in the body is a difficult task, as the epoxy fatty acids must first be obtained in significant amounts and with high purity. Obtaining compounds from natural sources is often labor intensive, and soluble epoxide hydrolases (sEH) rapidly hydrolyze the metabolites. On the other hand, obtaining these metabolites via chemical reactions is very inefficient, due to the difficulty of obtaining pure regioisomers and enantiomers, low yields, and extensive (and expensive) purification. Here, we present an efficient enzymatic synthesis of 19(S),20(R)- and 16(S),17(R)-epoxydocosapentaenoic acids (EDPs) from DHA via epoxidation with BM3, a bacterial CYP450 enzyme isolated originally from Bacillus megaterium (that is readily expressed in Escherichia coli). Characterization and determination of purity is performed with nuclear magnetic resonance spectroscopy (NMR), high-performance liquid chromatography (HPLC), and mass spectrometry (MS). This procedure illustrates the benefits of enzymatic synthesis of PUFA epoxy metabolites, and is applicable to the epoxidation of other fatty acids, including arachidonic acid (AA) and eicosapentaenoic acid (EPA) to produce the analogous epoxyeicosatrienoic acids (EETs) and epoxyeicosatetraenoic acids (EEQs), respectively.

We present a method useful for large-scale enzymatic synthesis and purification of specific enantiomers and regioisomers of epoxides of arachidonic acid (AA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA) with the use of a bacterial cytochrome P450 enzyme (BM3).

Enzymatische Synthese von epoxidierten Metaboliten von Docosahexaenoic, Eicosapentaenoic und Arachidonsäuren

The epoxidized metabolites of various polyunsaturated fatty acids (PUFAs), termed epoxy fatty acids, have a wide range of roles in human physiology. These ...

Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions

Aziridines, a class of reactive organic molecules containing a three-membered ring, are important synthons for the synthesis of a large variety of functionalized nitrogen-containing target compounds through the regiocontrolled ring-opening of C-substituted aziridines. Despite the tremendous progress in aziridine synthesis over the past decade, accessing contiguous bisaziridines efficiently remains difficult. Therefore, we were interested in synthesizing contiguous bisaziridines bearing an electronically diverse set of N-substituents beyond the single aziridine backbone for regioselective ring-opening reactions with diverse nucleophiles. In this study, chiral contiguous bisaziridines were prepared by organocatalytic asymmetric aziridination of chiral (E)-3-((S)-1-((R)-1-phenylethyl)aziridin-2-yl)acrylaldehyde with N-Ts-O-tosyl or N-Boc-O-tosyl hydroxylamine as the nitrogen source in the presence of (2S)-[diphenyl(trimethylsilyloxy)methyl]pyrrolidine as a chiral organocatalyst. Also demonstrated here are representative examples of regioselective ring-opening reactions of contiguous bisaziridines with a variety of nucleophiles such as sulfur, nitrogen, carbon, and oxygen, and the application of contiguous bisaziridines to the synthesis of multi-substituted chiral pyrrolidines by Pd-catalyzed hydrogenation.

Contiguous bisaziridines containing non-activated and activated aziridines were synthesized by asymmetric organocatalytic aziridinations and then subjected to chemoselective ring-opening reactions under acidic or basic conditions. The non-activated aziridine ring opens with less reactive nucleophiles under acidic conditions, whereas the activated aziridine ring opens with more reactive nucleophiles under basic conditions.

Herstellung zusammenhängender Bisaziridine für regioselektive Ringöffnungsreaktionen

Aziridines, a class of reactive organic molecules containing a three-membered ring, are important synthons for the synthesis of a large variety of ...

Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers

The growing consumption of synthetic polymers and the accumulation of polymer waste have led to a pressing need for new routes to sustainable materials. Achieving a closed-loop polymer economy via chemical recycling to monomer (CRM) is one such promising route. Our group recently reported a new CRM system based on polymers prepared by ring-opening metathesis polymerization (ROMP) of trans-cyclobutane fused cyclooctene (tCBCO) monomers. This system offers several key advantages, including the ease of polymerization at ambient temperatures, quantitative depolymerization to monomers under mild conditions, and a broad range of functionalities and thermomechanical properties. Here, we outline detailed protocols for the preparation of tCBCO-based monomers and their corresponding polymers, including the preparation of elastic polymer networks and compression molding of linear thermoplastic polymers. We also outline the preparation of high ring strain E-alkene tCBCO monomers and their living polymerization. Finally, the procedures for the depolymerization of linear polymers and polymer networks are also demonstrated.

Here, we describe protocols for the preparation of trans-cyclobutane fused cyclooctenes (tCBCO),&#160;their polymerization to prepare depolymerizable olefinic polymers, and the depolymerization of these polymers under mild conditions. Additionally, protocols for the preparation of depolymerizable networks and compression molding of rigid linear plastics based on this system are described.

Depolymerisierbare olefinische Polymere auf Basis von Cyclooctenmonomeren mit Schmelzring

The growing consumption of synthetic polymers and the accumulation of polymer waste have led to a pressing need for new routes to sustainable materials. ...