Eczacılık Fakültesi (Sydney Üniversitesi), Erciyes Üniversitesi Araştırma Fonu ve TÜBİTAK&#39;ın (1059B141400496) mali desteğini kabul ediyoruz. Videoyu düzenlemek için Tim Harland&#39;a (University of Sydney) teşekkür ediyoruz.

<ol>
	<li>Akkoc, S., Gok, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis+and+characterization+of+1-phenyl-3-alkylbenzimidazol-2-ylidene+salts+and+their+catalytic+activities+in+the+Heck+and+Suzuki+cross-coupling+reactions.">Synthesis and characterization of 1-phenyl-3-alkylbenzimidazol-2-ylidene salts and their catalytic activities in the Heck and Suzuki cross-coupling reactions.</a> J. Coord. Chem. 66 (8), 1396-1404 (2013).</li><li>Aktas, A., Akkoc, S., Gok, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Palladium+catalyzed+Mizoroki-Heck+and+Suzuki-Miyaura+reactions+using+naphthalenomethyl-substituted+imidazolidin-2-ylidene+ligands+in+aqueous+media.">Palladium catalyzed Mizoroki-Heck and Suzuki-Miyaura reactions using naphthalenomethyl-substituted imidazolidin-2-ylidene ligands in aqueous media.</a> J. Coord. Chem. 66 (16), 2901-2909 (2013).</li><li>Cetinkaya, B., Alici, B., Ozdemir, I., Bruneau, C., Dixneuf, P. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=2-imidazoline+and+1,4,5,6-tetrahydropyrimidine-ruthenium(II)+complexes+and+catalytic+synthesis+of+furan.">2-imidazoline and 1,4,5,6-tetrahydropyrimidine-ruthenium(II) complexes and catalytic synthesis of furan.</a> J. Organomet. Chem. 575 (2), 187-192 (1999).</li><li>Chouthaiwale, P. V., Rawat, V., Sudalai, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pd-catalyzed+selective+hydrosilylation+of+aryl+ketones+and+aldehydes.">Pd-catalyzed selective hydrosilylation of aryl ketones and aldehydes.</a> Tetrahedron Lett. 53 (2), 148-150 (2012).</li><li>Herrmann, W. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=N-heterocyclic+carbenes:+A+new+concept+in+organometallic+catalysis.">N-heterocyclic carbenes: A new concept in organometallic catalysis.</a> Angew. Chem. Int. Ed. 41 (8), 1290-1309 (2002).</li><li>Jensen, T. R., Schaller, C. P., Hillmyer, M. A., Tolman, W. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Zinc+N-heterocyclic+carbene+complexes+and+their+polymerization+of+D,L-lactide.">Zinc N-heterocyclic carbene complexes and their polymerization of D,L-lactide.</a> J. Organomet. Chem. 690 (24-25), 5881-5891 (2005).</li><li>Lai, Y. B., Lee, C. S., Lin, W. J., Naziruddin, A. R., Hwang, W. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bis-chelate+N-heterocyclic+tetracarbene+Ru(II)+complexes:+Synthesis,+structure,+and+catalytic+activity+toward+transfer+hydrogenation+of+ketones.">Bis-chelate N-heterocyclic tetracarbene Ru(II) complexes: Synthesis, structure, and catalytic activity toward transfer hydrogenation of ketones.</a> Polyhedron. 53, 243-248 (2013).</li><li>Savka, R. D., Plenio, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+hexahydro-s-indacene+based+NHC+ligand+for+olefin+metathesis+catalysts.">A hexahydro-s-indacene based NHC ligand for olefin metathesis catalysts.</a> J. Organomet. Chem. 710, 68-74 (2012).</li><li>Yigit, M., Yigit, B., Gok, Y. <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+novel+palladium(II)+N-heterocyclic+carbene+complexes+and+their+catalytic+activities+in+the+direct+C5+arylation+reactions.">Synthesis of novel palladium(II) N-heterocyclic carbene complexes and their catalytic activities in the direct C5 arylation reactions.</a> Inorg. Chim. Acta. 453, 23-28 (2016).</li><li>Yasar, S., Sahin, C., Arslan, M., Ozdemir, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis,+characterization+and+the+Suzuki-Miyaura+coupling+reactions+of+N-heterocyclic+carbene-Pd(II)-pyridine+(PEPPSI)+complexes.">Synthesis, characterization and the Suzuki-Miyaura coupling reactions of N-heterocyclic carbene-Pd(II)-pyridine (PEPPSI) complexes.</a> J. Organomet. Chem. 776, 107-112 (2015).</li><li>Ozdemir, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=N-Heterocyclic+carbenes:+Useful+ligands+for+the+palladium-catalysed+direct+C5+arylation+of+heteroaromatics+with+aryl+bromides+or+electron-deficient+aryl+chlorides.">N-Heterocyclic carbenes: Useful ligands for the palladium-catalysed direct C5 arylation of heteroaromatics with aryl bromides or electron-deficient aryl chlorides.</a> Eur. J. Inorg. Chem. 12 (12), 1798-1805 (2010).</li><li>Clavier, H., Nolan, S. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=N-heterocyclic+carbene+and+phosphine+ruthenium+indenylidene+precatalysts:+A+comparative+study+in+Olefin+metathesis.">N-heterocyclic carbene and phosphine ruthenium indenylidene precatalysts: A comparative study in Olefin metathesis.</a> Chem. Eur. J. 13 (28), 8029-8036 (2007).</li><li>Johnson, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Catalyzed+reactions+of+acyl+anion+equivalents.">Catalyzed reactions of acyl anion equivalents.</a> Angew. Chem. Int. Ed. 43 (11), 1326-1328 (2004).</li><li>Marion, N., Diez-Gonzalez, S., Nolan, S. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=N-heterocyclic+carbenes+as+organocatalysts.">N-heterocyclic carbenes as organocatalysts.</a> Angew. Chem. Int. Ed. 46 (17), 2988-3000 (2007).</li><li>Perry, M. C., Burgess, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chiral+N-heterocyclic+carbene-transition+metal+complexes+in+asymmetric+catalysis.">Chiral N-heterocyclic carbene-transition metal complexes in asymmetric catalysis.</a> Tetrahedron: Asymmetry. 14 (8), 951-961 (2003).</li><li>Zeitler, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Extending+mechanistic+routes+in+heterazolium+catalysis-promising+concepts+for+versatile+synthetic+methods.">Extending mechanistic routes in heterazolium catalysis-promising concepts for versatile synthetic methods.</a> Angew. Chem. Int. Ed. 44 (46), 7506-7510 (2005).</li><li>Schwarz, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=N-Heterocyclic+carbenes,+part+25+-+Polymer-supported+carbene+complexes+of+palladium:+Well-defined,+air-stable,+recyclable+catalysts+for+the+Heck+reaction.">N-Heterocyclic carbenes, part 25 - Polymer-supported carbene complexes of palladium: Well-defined, air-stable, recyclable catalysts for the Heck reaction.</a> Chem. Eur. J. 6 (10), 1773-1780 (2000).</li><li>Akkoc, S., Gok, Y., Ilhan, I. O., Kayser, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=N-Methylphthalimide-substituted+benzimidazolium+salts+and+PEPPSI+Pd-NHC+complexes:+synthesis,+characterization+and+catalytic+activity+in+carbon-carbon+bond-forming+reactions.">N-Methylphthalimide-substituted benzimidazolium salts and PEPPSI Pd-NHC complexes: synthesis, characterization and catalytic activity in carbon-carbon bond-forming reactions.</a> Beilstein J. Org. Chem. 12, 81-88 (2016).</li><li>Karaca, E. O., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Palladium+complexes+with+tetrahydropyrimidin-2-ylidene+ligands:+Catalytic+activity+for+the+direct+arylation+of+furan,+thiophene,+and+thiazole+derivatives.">Palladium complexes with tetrahydropyrimidin-2-ylidene ligands: Catalytic activity for the direct arylation of furan, thiophene, and thiazole derivatives.</a> Organometallics. 34 (11), 2487-2493 (2015).</li><li>Ozdemir, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=N-Heterocyclic+carbene-palladium+catalysts+for+the+direct+arylation+of+pyrrole+derivatives+with+aryl+chlorides.">N-Heterocyclic carbene-palladium catalysts for the direct arylation of pyrrole derivatives with aryl chlorides.</a> Beilstein J. Org. Chem. 9, 303-312 (2013).</li><li>Senocak, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthesis,+crystal+structures,+magnetic+properties+and+Suzuki+and+Heck+coupling+catalytic+activities+of+new+coordination+polymers+containing+tetracyanopalladate(II)+anions.">Synthesis, crystal structures, magnetic properties and Suzuki and Heck coupling catalytic activities of new coordination polymers containing tetracyanopalladate(II) anions.</a> Polyhedron. 49 (1), 50-60 (2013).</li><li>Akkoc, S., Gok, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dichlorido(3-chloropyridine-N)+1,3-dialkylbenzimidazol-2-ylidene+palladium(II)+complexes:+Synthesis,+characterization+and+catalytic+activity+in+the+arylation+reaction.">Dichlorido(3-chloropyridine-N) 1,3-dialkylbenzimidazol-2-ylidene palladium(II) complexes: Synthesis, characterization and catalytic activity in the arylation reaction.</a> Inorg. Chim. Acta. 429, 34-38 (2015).</li><li>Akkoc, S., Gok, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Catalytic+activities+in+direct+arylation+of+novel+palladium+N-heterocyclic+carbene+complexes.">Catalytic activities in direct arylation of novel palladium N-heterocyclic carbene complexes.</a> Appl. Organomet. Chem. 28 (12), 854-860 (2014).</li><li>Akkoc, S., Gok, Y., Ilhan, I. O., Kayser, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+situ+Generation+of+Efficient+Palladium+N-heterocyclic+Carbene+Catalysts+Using+Benzimidazolium+Salts+for+the+Suzuki-Miyaura+Cross-coupling+Reaction.">In situ Generation of Efficient Palladium N-heterocyclic Carbene Catalysts Using Benzimidazolium Salts for the Suzuki-Miyaura Cross-coupling Reaction.</a> Curr. Org. Synth. 13 (5), 761-766 (2016).</li></ol>

Yazarların açıklayacak bir şeyi yok.

Dört benzimidazolyum tuzunun sentezi ve saflaştırılması için protokoller ve daha sonra bunların paladyum NHC kompleksleri kasıtlı olarak, genç bilim insanlarına veya tarlalara yeni gelen kişilere yardımcı olmak için kasıtlı bir şekilde sunulmuştur. Bu aynı amaç göz önüne alındığında, arilasyon ve Suzuki-Miyaura reaksiyonlarındaki dört kompleksin katalitik aktivitesini test etme protokolleri de son derece ayrıntılı olarak sunuldu. Ayrıca protokolleri başkalarının kendilerini diğer bi...

N -heterosiklik karbenler (NHCs) özellikle metatez, furan oluşturma, polimerizasyon, hidrosililasyon, hidrojenasyon, arillenme, Suzuki-Miyaura çapraz bağlama ve Mizoroki-Heck çapraz bağlama gibi çeşitli önemli reaksiyonları katalizleme yetenekleri açısından çok dikkat çekmiştir 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 . NHC&#39;ler metallerle birleştirilebilir; Bu gibi metal-NHC kompleksleri, yardımcı metal ligandları olarak geçiş metali katalizli reaksiyonlarda yaygın olarak kullanılmaktadır ve organokatalizörler 12 , 13 , 14 , </Sup&gt; 15 , 16 . Genellikle metal-karbon koordinasyon bağlarının yüksek ayrışma enerjilerinin bir sonucu olarak hava, nem ve ısıya karşı olağanüstü kararlıdırlar 17 . Burada, dört benzimidazolyum tuzunun (bileşik 1 - 4 ) ve bunların paladyum NHC komplekslerinin (sırasıyla bileşik 5 - 8 ) sentezi ve saflaştırılması için protokoller ayrıntılı olarak belirtilmiştir 18 . Tuzlar ve kompleksler daha önce çeşitli teknikler kullanılarak karakterize edildi 18 . Arilasyon ve Suzuki-Miyaura çapraz bağlanma reaksiyonları 9 , 10 , 11&#39;in katalizörü için benzer bileşikler kullanıldığından, arilasyon ve Suzuki-Miyaura reaksiyonlarındaki komplekslerin katalitik aktivitesinin test edilmesi için protokoller aDetaylı. Önemlisi, komplekslerin katalitik aktivitesini sentezleme, saflaştırma ve test etme protokolleri, yeni paladyum NHC komplekslerine kolay adaptasyon sağlayacak kadar genel olarak sunulmuştur.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>1-chloro-4-nitrobenzene</td>
			<td>Sigma-Aldrich (Interlab A.S., USA)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>2,5-dimethoxyphenylboronic acid</td>
			<td>Sigma-Aldrich (Interlab A.S., USA)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>2-n-butylfuran</td>
			<td>Sigma-Aldrich (Interlab A.S., USA)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>2-n-butylthiophene</td>
			<td>Sigma-Aldrich (Interlab A.S., USA)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>3-chloropyridine</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>4-bromoacetophenone</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>4-bromoanisole</td>
			<td>Sigma-Aldrich (Interlab A.S., USA)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>4-chlorotoluene</td>
			<td>Sigma-Aldrich (Interlab A.S., USA)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>4-methoxy-1-chlorobenzene</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>4-tert-butylphenylboronic acid</td>
			<td>Sigma-Aldrich (Interlab A.S., USA)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Benzimidazole</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Bromobenzene</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Celite</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Dichloromethane</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Diethyl ether</td>
			<td>Sigma-Aldrich (Interlab A.S., USA)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Ethyl acetate</td>
			<td>Sigma-Aldrich (Interlab A.S., USA)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Ethyl alcohol</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Hexane</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Magnesium sulfate</td>
			<td>Scharlau (Barcelona, Spain)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>N,N-dimethylacetamide</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>N,N-dimethylformamide</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Palladium chloride</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Phenylboronic acid</td>
			<td>Sigma-Aldrich (Interlab A.S., USA)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Potassium acetate</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Potassium carbonate</td>
			<td>Scharlau (Barcelona, Spain)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Potassium hydroxide</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Silica gel</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium tert-butoxide</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Thianaphthene-2-boronic acid</td>
			<td>Sigma-Aldrich (Interlab A.S., USA)</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

palladium n-heterocyclic carbene complexes: synthesis from benzimidazolium salts and catalytic activity in carbon-carbon bond-forming reactions

Benzimidazolyum tuzlarından dört paladyum N -heterosiklik karben kompleksinin sentezi ve daha sonra saflaştırılması için ayrıntılı ve genel protokoller sunulmuştur. Bu gibi komplekslerin arilasyon ve Suzuki-Miyaura çapraz bağlanma tepkimelerinde katalitik aktivitesinin test edilmesi için ayrıntılı ve genel protokoller de sunulmuştur. Arilasyon ve Suzuki-Miyaura tipi reaksiyonlarda dört kompleksin katalitik aktivitesi için temsilci sonuçları gösterilmektedir. İncelenen reaksiyonların her biri için, dört kompleksden en az bir tanesi reaksiyonu başarıyla katalize etti ve birçok karbon-karbon bağını oluşturan reaksiyonların katalizörü için umut verici adaylar olarak nitelendirdi. Sunulan protokoller, yeni paladyum N -heterosiklik karben komplekslerinin sentezi, arıtılması ve katalitik aktivite testleri için uyarlanacak kadar geneldir.

Benzimidazolyum tuzları ( l - 4 ) ( Şekil 1 ), N- alkilbenzimidazolleri ve çeşitli alkil halojenürleri kullanarak susuz DMF içerisinde sentezlendi, daha sonra saflaştırıldı ve 18 , 24 öncesi rapor edildiği gibi karakterize edildi. Bunlar beyaz veya krem ​​rengi katılardır ve verimi% 62 ila% 97 arasında değişirler. Paladyum NHC kompleksle...

Watch this Scientific Journal Video about Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions at JoVE.com

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

Benzimidazolyum tuzlarından dört paladyum N -heterosiklik karben kompleksinin sentezi ve daha sonra saflaştırılması için ayrıntılı ve genel protokoller sunulmuştur. Kompleksler, arilasyon ve Suzuki-Miyaura reaksiyonlarında katalitik etkinlik açısından test edildi. İncelenen her reaksiyon için, dört kompleksden en az biri reaksiyonu başarıyla katalize etti.

palladyum<em&gt; K</em&gt; -Heterosiklik Karben Kompleksleri: Benzimidazolyum Tuzlarından Sentez ve Karbon-karbon Bağ Oluşturma Reaksiyonlarında Katalitik Aktivite

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

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

Chemical Bonding: Basic Concepts

SCIENTISTS IN ACTION

9.6K Görüntüleme.  The University of Sydney.  Benzimidazolyum tuzlarından dört paladyum N -heterosiklik karben kompleksinin sentezi ve daha sonra saflaştırılması için ayrıntılı ve genel protokoller sunulmuştur. Kompleksler, arilasyon ve Suzuki-Miyaura reaksiyonlarında katalitik etkinlik açısından test edildi. İncelenen her reaksiyon için, dört kompleksden en az biri reaksiyonu başarıyla katalize etti. 

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

Preparation and Use of Samarium Diiodide (SmI2) in Organic Synthesis: The Mechanistic Role of HMPA and Ni(II) Salts in the Samarium Barbier Reaction

Although initially considered an esoteric reagent, SmI2 has become a common tool for synthetic organic chemists. SmI2 is generated through the addition of molecular iodine to samarium metal in THF.1,2-3 It is a mild and selective single electron reductant and its versatility is a result of its ability to initiate a wide range of reductions including C-C bond-forming and cascade or sequential reactions. SmI2 can reduce a variety of functional groups including sulfoxides and sulfones, phosphine oxides, epoxides, alkyl and aryl halides, carbonyls, and conjugated double bonds.2-12 One of the fascinating features of SmI-2-mediated reactions is the ability to manipulate the outcome of reactions through the selective use of cosolvents or additives. In most instances, additives are essential in controlling the rate of reduction and the chemo- or stereoselectivity of reactions.13-14 Additives commonly utilized to fine tune the reactivity of SmI2 can be classified into three major groups: (1) Lewis bases (HMPA, other electron-donor ligands, chelating ethers, etc.), (2) proton sources (alcohols, water etc.), and (3) inorganic additives (Ni(acac)2, FeCl3, etc).3
Understanding the mechanism of SmI2 reactions and the role of the additives enables utilization of the full potential of the reagent in organic synthesis. The Sm-Barbier reaction is chosen to illustrate the synthetic importance and mechanistic role of two common additives: HMPA and Ni(II) in this reaction. The Sm-Barbier reaction is similar to the traditional Grignard reaction with the only difference being that the alkyl halide, carbonyl, and Sm reductant are mixed simultaneously in one pot.1,15 Examples of Sm-mediated Barbier reactions with a range of coupling partners have been reported,1,3,7,10,12 and have been utilized in key steps of the synthesis of large natural products.16,17 Previous studies on the effect of additives on SmI2 reactions have shown that HMPA enhances the reduction potential of SmI2 by coordinating to the samarium metal center, producing a more powerful,13-14,18 sterically encumbered reductant19-21 and in some cases playing an integral role in post electron-transfer steps facilitating subsequent bond-forming events.22 In the Sm-Barbier reaction, HMPA has been shown to additionally activate the alkyl halide by forming a complex in a pre-equilibrium step.23
Ni(II) salts are a catalytic additive used frequently in Sm-mediated transformations.24-27 Though critical for success, the mechanistic role of Ni(II) was not known in these reactions. Recently it has been shown that SmI2 reduces Ni(II) to Ni(0), and the reaction is then carried out through organometallic Ni(0) chemistry.28
These mechanistic studies highlight that although the same Barbier product is obtained, the use of different additives in the SmI2 reaction drastically alters the mechanistic pathway of the reaction. The protocol for running these SmI2-initiated reactions is described.

Preparation and Use of Samarium Diiodide SmI2 in Organic Synthesis: The Mechanistic Role of HMPA and NiII Salts in the Samarium Barbier Reaction

A straightforward procedure for the preparation of samarium diiodide (SmI2) in THF is described. The role of two main additives namely hexamethylphosphoramide (HMPA) and Ni(acac)2 in Sm mediated reactions is demonstrated in the Sm-Barbier reaction.

Hazırlanması ve Samaryum Diiodide Kullanımı (SMI<sub&gt; 2</sub&gt;) In Organic Synthesis: Samaryum Barbier Reaksiyonu HMPA ve Ni (II) tuzlarının Mekanistik Rolü

Although initially considered an esoteric reagent, SmI2 has become a common tool for synthetic organic chemists. SmI2 is generated through the addition of ...

Kimya

Anticancer Metal Complexes: Synthesis and Cytotoxicity Evaluation by the MTT Assay

Titanium (IV) and vanadium (V) complexes are highly potent anticancer agents. A challenge in their synthesis refers to their hydrolytic instability; therefore their preparation should be conducted under an inert atmosphere. Evaluation of the anticancer activity of these complexes can be achieved by the MTT assay.
The MTT assay is a colorimetric viability assay based on enzymatic reduction of the MTT molecule to formazan when it is exposed to viable cells. The outcome of the reduction is a color change of the MTT molecule. Absorbance measurements relative to a control determine the percentage of remaining viable cancer cells following their treatment with varying concentrations of a tested compound, which is translated to the compound anticancer activity and its IC50 values. The MTT assay is widely common in cytotoxicity studies due to its accuracy, rapidity, and relative simplicity.
Herein we present a detailed protocol for the synthesis of air sensitive metal based drugs and cell viability measurements, including preparation of the cell plates, incubation of the compounds with the cells, viability measurements using the MTT assay, and determination of IC50 values.

A method for synthesis of air-sensitive titanium and vanadium anticancer agents is described, along with the evaluation of their cytotoxic activity towards human cancer cell line by the MTT Assay.

MTT deneyi ile sentez ve Sitotoksisite Değerlendirilmesi: Anticancer Metal Kompleksleri

Titanium (IV) and vanadium (V) complexes are highly potent anticancer agents. A challenge in their synthesis refers to their hydrolytic instability; ...

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

Unsymmetrical 1,2-diols are hardly accessible by reductive pinacol coupling processes. A successful execution of such a transformation is bound to a clear recognition and strict differentiation of two similar carbonyl compounds (aldehydes &#8594; secondary 1,2-diols or ketones &#8594; tertiary 1,2-diols). This fine-tuning is still a challenge and an unsolved problem for an organic chemist. There exist several reports on successful execution of this transformation but they cannot be generalized. Herein we describe a catalytic direct pinacol coupling process which proceeds via a retropinacol/cross-pinacol coupling sequence. Thus, unsymmetrical substituted 1,2-diols can be accessed with almost quantitative yields by means of an&#160;operationally simple performance under very mild conditions. Artificial techniques, such as syringe-pump techniques or delayed additions of reactants are not necessary. The procedure we describe provides a very rapid access to cross-pinacol products (1,2-diols, vicinal diols). A further extension of this new process, e.g. an enantioselective performance could provide a very useful tool for the synthesis of unsymmetrical chiral 1,2-diols.

A novel account for the synthesis of unsymmetrical 1,2-diols based on a retropinacol/cross-pinacol coupling mechanism is described. Due to the catalytic execution of this reaction a considerable improvement compared to conventional cross-pinacol couplings is achieved.

Retropinacol / Çapraz pinakol Kavrama Reaksiyonları - 1,2-Asimetrik Diollerin A Katalitik Erişim

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

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',1''-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.

Hafif reaksiyon koşulları altında paladyum - Dikloro {bis [(phosphinetriyl) tripiperidine 1,1 &#39;, 1&#39;&#39;]} katalize Mizoroki-Heck Çapraz bağlama reaksiyonları

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 ...

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.

Sentezi ve Mezogözenekli Silika Walls Altın interkalasyonlu Katalitik Performans

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

Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts

Ynones are a valuable functional group and building block in organic synthesis. Ynones serve as a precursor to many important organic functional groups and scaffolds. Traditional methods for the preparation of ynones are associated with drawbacks including harsh conditions, multiple purification steps, and the presence of unwanted byproducts. An alternative method for the straightforward preparation of ynones from acyl chlorides and potassium alkynyltrifluoroborate salts is described herein. The adoption of organotrifluoroborate salts as an alternative to organometallic reagents for the formation of new carbon-carbon bonds has a number of advantages. Potassium organotrifluoroborate salts are shelf stable, have good functional group tolerance, low toxicity, and a wide variety are straightforward to prepare. The title reaction proceeds rapidly at ambient temperature in the presence of a Lewis acid without the exclusion of air and moisture. Fair to excellent yields may be obtained via reaction of various aryl and alkyl acid chlorides with alkynyltrifluoroborate salts in the presence of boron trichloride.

The goal of this manuscript is to demonstrate a straightforward method for the preparation of ynones from acyl chloride and potassium alkynyltrifluoroborate salt starting materials. The one-pot reaction proceeds rapidly in the presence of boron trichloride without exclusion of air and moisture.

Asil klorür ve potasyum Alkynyltrifluoroborate Tuzlarından Ynones Metal içermeyen sentezi

Ynones are a valuable functional group and building block in organic synthesis. Ynones serve as a precursor to many important organic functional groups ...

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes

Herein we report the synthesis of a tridentate phosphine ligand N(CH2PPh2)3 (N-triphosPh) (1) via a phosphorus based Mannich reaction of the hydroxylmethylene phosphine precursor with ammonia in methanol under a nitrogen atmosphere. The N-triphosPh ligand precipitates from the solution after approximately 1 hr of reflux and can be isolated analytically pure via simple cannula filtration procedure under nitrogen. Reaction of the N-triphosPh ligand with [Ru3(CO)12] under reflux affords a deep red solution that show evolution of CO gas on ligand complexation. Orange crystals of the complex [Ru(CO)2{N(CH2PPh2)3}-&#954;3P] (2) were isolated on cooling to RT. The 31P{1H} NMR spectrum showed a characteristic single peak at lower frequency compared to the free ligand. Reaction of a toluene solution of complex 2 with oxygen resulted in the instantaneous precipitation of the carbonate complex [Ru(CO3)(CO){N(CH2PPh2)3}-&#954;3P] (3) as an air stable orange solid. Subsequent hydrogenation of 3 under 15 bar of hydrogen in a high-pressure reactor gave the dihydride complex [RuH2(CO){N(CH2PPh2)3}-&#954;3P] (4), which was fully characterized by X-ray crystallography and NMR spectroscopy. Complexes 3 and 4 are potentially useful catalyst precursors for a range of hydrogenation reactions, including biomass-derived products such as levulinic acid (LA). Complex 4 was found to cleanly react with LA in the presence of the proton source additive NH4PF6 to give [Ru(CO){N(CH2PPh2)3}-&#954;3P{CH3CO(CH2)2CO2H}-&#954;2O](PF6) (6).

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes

Ruthenium phosphine complexes are widely used for homogeneous catalytic reactions such as hydrogenations. The synthesis of a series of novel tridentate ruthenium complexes bearing the N-triphos ligand N(CH2PPh2)3 is reported. Additionally, the stoichiometric reaction of a dihydride Ru&#8211;N-triphos complex with levulinic acid is described.

Rutenyum bir Serisi Sentezi, Karakterizasyonu ve Tepkime<em&gt; K</em&gt; -triphos<sup&gt; Ph</sup&gt; Kompleksi

Herein we report the synthesis of a tridentate phosphine ligand N(CH2PPh2)3 (N-triphosPh) (1) via a phosphorus based Mannich reaction of the ...

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.

Katalitik Kırma Dönüşüm aracılığıyla Kanola Yağı gelen Biyoyakıt ve Biochemicals laboratuvar üretimi

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 ...

Enzymatic Cascade Reactions for the Synthesis of Chiral Amino Alcohols from L-lysine

Amino alcohols are versatile compounds with a wide range of applications. For instance, they have been used as chiral scaffolds in organic synthesis. Their synthesis by conventional organic chemistry often requires tedious multi-step synthesis processes, with difficult control of the stereochemical outcome. We present a protocol to enzymatically synthetize amino alcohols starting from the readily available L-lysine in 48 h. This protocol combines two chemical reactions that are very difficult to conduct by conventional organic synthesis. In the first step, the regio- and diastereoselective oxidation of an unactivated C-H bond of the lysine side-chain is catalyzed by a dioxygenase; a second regio- and diastereoselective oxidation catalyzed by a regiodivergent dioxygenase can lead to the formation of the 1,2-diols. In the last step, the carboxylic group of the alpha amino acid is cleaved by a pyridoxal-phosphate (PLP) decarboxylase (DC). This decarboxylative step only affects the alpha carbon of the amino acid, retaining the hydroxy-substituted stereogenic center in a beta/gamma position. The resulting amino alcohols are therefore optically enriched. The protocol was successfully applied to the semipreparative-scale synthesis of four amino alcohols. Monitoring of the reactions was conducted by high performance liquid chromatography (HPLC) after derivatization by 1-fluoro-2,4-dinitrobenzene. Straightforward purification by solid-phase extraction (SPE) afforded the amino alcohols with excellent yields (93% to &#62;95%).

Chiral amino alcohols are versatile molecules for use as scaffolds in organic synthesis. Starting from L-lysine, we synthesize amino alcohols by an enzymatic cascade reaction combining diastereoselective C-H oxidation catalyzed by dioxygenase followed by cleavage of the carboxylic acid moiety of the corresponding hydroxyl amino acid by a decarboxylase.

Enzimatik Cascade reaksiyonlardan L-lizin Amino kiral alkoller sentezi için

Amino alcohols are versatile compounds with a wide range of applications. For instance, they have been used as chiral scaffolds in organic synthesis. ...

Chemical Precipitation Method for the Synthesis of Nb2O5 Modified Bulk Nickel Catalysts with High Specific Surface Area

We demonstrate a method for the synthesis of NixNb1-xO catalysts with sponge-like and fold-like nanostructures. By varying the Nb:Ni ratio, a series of NixNb1-xO nanoparticles with different atomic compositions (x = 0.03, 0.08, 0.15, and 0.20) have been prepared by chemical precipitation. These NixNb1-xO catalysts are characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy. The study revealed the sponge-like and fold-like appearance of Ni0.97Nb0.03O and Ni0.92Nb0.08O on the NiO surface, and the larger surface area of these NixNb1-xO catalysts, compared with the bulk NiO. Maximum surface area of 173 m2/g can be obtained for Ni0.92Nb0.08O catalysts. In addition, the catalytic hydroconversion of lignin-derived compounds using the synthesized Ni0.92Nb0.08O catalysts have been investigated.

Chemical Precipitation Method for the Synthesis of Nb2O5 Modified Bulk Nickel Catalysts with High Specific Surface Area

A protocol for the synthesis of sponge-like and fold-like Ni1-xNbxO nanoparticles by chemical precipitation is presented.

Nb2O5 sentezi için kimyasal yağış yöntemi toplu nikel katalizör yüksek belirli yüzey alanı ile modifiye

We demonstrate a method for the synthesis of NixNb1-xO catalysts with sponge-like and fold-like nanostructures. By varying the Nb:Ni ratio, a series of ...