Name: syntheses, crystallization, and spectroscopic characterization of 3,5-lutidine n-oxide dehydrate
Uploaded: 2018-04-24T14:00:00.000+00:00
Duration: 6 min 18 s
Description: Watch this Scientific Journal Video about Syntheses, Crystallization, and Spectroscopic Characterization of 3,5-Lutidine N-Oxide Dehydrate at JoVE.com

現在の仕事は、Vicerrectoría ・ デ ・危惧 y プロジェクト号、科学の漏洩 BUAP から領土・ デ ・ Posgrado によってサポートされています。REOY-NAT14、15、16-G. 砥-NAT17。RMG は CONACyT (メキシコ) の奨学金 417887 をありがちましょう。

1. 反応
<ol><li>発煙のフード 0.5 mol (29.8 mL) 氷酢酸と開かれたラウンド 100 mL フラスコを配置し、3, 5-dimethylpyridine と H2O2 (35%) 5 mL 0.051 mol (5.82 mL) を追加します。5 h で 80 ° C の内部温度で一定の電磁攪拌下で混合物の反応をしてください。</li>
	<li>反応時間後氷 (氷酢酸ガスを公開を行う)、24 ° C に、フラスコを冷却し、過剰の酢酸を削除する 90-120 分間高真空蒸留ユニットに差し込みます。 注意: は、ホット マテリアルを使用しないでください。ガラス管理可能な温度に達するまで待機します。また、これは常圧蒸留装置の上部に入る蒸気を避けます。</li>
	<li>できるだけ多く酢酸の混合物に集中して痕跡の除去を確実に 2 回蒸留水 (10 mL) を追加します。</li>
</ol>2. 塩基度調整と抽出
<ol><li>Bi 芳醇水に分離の粘性と透明の製品を溶解し、純粋な固体 Na2CO310 pH 調整にポテンショメータを使用します。</li>
	<li>250 mL 分離漏斗で慎重にソリューションを配置し、5 回収穫を改良する CHCl3 250 mL で抽出します。有機層を回復し、固体の Na2以上だから乾燥 30 分、最大の製品が含まれる4 。必要に応じて、再 CHCl3の希望の金額で水相を抽出します。 注意: CHCl3は眠気やめまい; を引き起こす可能性があります。ケアとヒューム フードの中を処理します。</li>
	<li>非常に吸湿性のクリア ベージュ結晶性粉末 (70%) を形成するまで高真空蒸留装置で減圧下で溶媒を削除します。</li>
</ol>3. 結晶化過程
<ol><li>冷たい高実行される液体クロマトグラフィー (HPLC) グレード ジエチル エーテル 50 mL で結晶性の粉末の 4.3 g を溶解します。真空フィルター固体原料または塵のすべてのトレースを削除するソリューションです。濾液をガラス シャーレに注ぎ、研究所の冷蔵庫に 4 ° C で蒸発を遅らせるためにそれを残してします。</li>
	<li>2 日後、明確な無色の結晶が得られることを確認します。310 311 K の範囲にあるべき融点を測定し</li>
</ol>4. 3, 5-ルチジンn-酸化物 Dehydrate の解析
<ol><li>さらに x 線分析用フラスコの壁からデカンテーションによってして角柱形状および無色に形成される結晶を削除します。直後ではなくを使用する場合は、結晶にジエチル エーテル結晶水和を避けるためにしてください。</li>
	<li>0.010 g 3, 5-ルチジンN酸化物の NMR H1と C13分析手順の有効性を証明するために行うため CDCl3 0.4 mL に脱水を解消します。</li>
</ol>

<ol>
	<li>Ochiai, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+Japanese+work+on+the+chemistry+of+pyridine+1-oxide+and+related+compounds.">Recent Japanese work on the chemistry of pyridine 1-oxide and related compounds.</a> J. Org. Chem. 18 (5), 534-551 (1953).</li><li>Solomons, T. W. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Organic Chemistry 2nd Edition. , 1110 (1976).</li><li>Albini, A., Pietra, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Heterocyclic N-Oxides. , 328 (1991).</li><li>Koukal, P., Ulc, J., Necas, D., Kotora, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Heterocyclic+N.-Oxides.">Heterocyclic N.-Oxides.</a> Topics in Heterocyclic Chemistry. 53, 29-58 (2017).</li><li>Wen-Man, Z., Jian-Jun, D., Xu, J., Jun, X., Huan-Jian, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Visible-Light-Induced+C2+alkylation+of+pyridine+N.-oxides.">Visible-Light-Induced C2 alkylation of pyridine N.-oxides.</a> J. Org. Chem. 82 (4), 2059-2066 (2017).</li><li>Merino Garc&#237;a, M. R., R&#237;os-Merino, F. J., Bern&#232;s, S., Reyes-Ortega, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Crystal+structure+of+3,5-dimethylpyridine+N-oxide+dihydrate.">Crystal structure of 3,5-dimethylpyridine N-oxide dihydrate.</a> Acta Cryst. 72 (12), 1687-1690 (2016).</li><li>Sarma, R., Karmakar, A., Baruah, J. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=N-Oxides+in+Metal-Containing+Multicomponent+Molecular+Complexes.">N-Oxides in Metal-Containing Multicomponent Molecular Complexes.</a> Inorg. Chem. 47 (3), 763-765 (2008).</li><li>Youssif, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+trends+in+the+chemistry+of+pyridine+N-oxides.">Recent trends in the chemistry of pyridine N-oxides.</a> ARKIVOC. 2001, 242-268 (2001).</li><li>Chucholowski, A. W., Uhlendorf, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Base+catalyzed+rearrangement+of+5-cyanomethyl-2-isoxazolines;+novel+pathway+for+the+formation+of+2-aminopyridine+N-oxides.">Base catalyzed rearrangement of 5-cyanomethyl-2-isoxazolines; novel pathway for the formation of 2-aminopyridine N-oxides.</a> Tetrahedron Lett. 31 (14), 1949-1952 (1990).</li><li>Thellend, A., Battioni, P., Sanderson, W., Mansuy, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Oxidation+of+N-Heterocycles+by+H2O2+Catalyzed+by+a+Mn-Porphyrin:+An+Easy+Access+to+N-Oxides+Under+Mild+Conditions.">Oxidation of N-Heterocycles by H2O2 Catalyzed by a Mn-Porphyrin: An Easy Access to N-Oxides Under Mild Conditions.</a> Synthesis. 1997 (12), 1387-1388 (1997).</li><li>Cop&#233;ret, C., Adolfson, H., Tinh-Alfredo, V. K. h., Yudin, A. K., Sharpless, K. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+simple+and+Efficient+Method+for+the+Preparation+of+Pyridine+N-Oxides.">A simple and Efficient Method for the Preparation of Pyridine N-Oxides.</a> J. Org. Chem. 63 (5), 1740-1741 (1998).</li><li>Ferrer, M., S&#225;nchez-Baeza, F., Messeguer, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+the+preparation+of+amine+N-oxides+by+using+dioxiranes.">On the preparation of amine N-oxides by using dioxiranes.</a> Tetrahedron. 53 (46), 15877-15888 (1997).</li><li>Adam, W., Briviba, K., Duschek, F., Golsch, D., Kiefer, W., Sies, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Formation+of+singlet+oxygen+in+the+deoxygenation+of+heteroarene+N-oxides+by+dimethyldioxirane.">Formation of singlet oxygen in the deoxygenation of heteroarene N-oxides by dimethyldioxirane.</a> J. Chem. Soc. Chem. Commun. 1995 (18), 1831-1832 (1995).</li><li>Murray, R. W., Singh, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Facile+One-Step+Synthesis+of+C-Arylnitrones+Using+Dimethyldioxirane.">A Facile One-Step Synthesis of C-Arylnitrones Using Dimethyldioxirane.</a> J.Org.Chem. 55 (9), 2954-2957 (1990).</li><li>Kim, S. W., Um, T., Shin, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Br&#248;nsted+acid-catalyzed+&#945;-halogenation+of+ynamides+from+halogenated+solvents+and+pyridine-N-oxides.">Br&#248;nsted acid-catalyzed &#945;-halogenation of ynamides from halogenated solvents and pyridine-N-oxides.</a> Chem. Commun. 53 (18), 2733-2736 (2017).</li><li>Campeau, L., Rousseaux, R., Fagnou, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+solution+to+the+2-pyridyl+organometallic+cross-coupling+problem:+regioselective+catalytic+direct+arylation+of+pyridine+N-oxides.">A solution to the 2-pyridyl organometallic cross-coupling problem: regioselective catalytic direct arylation of pyridine N-oxides.</a> J. Am. Chem. Soc. 127 (51), 18020-18021 (2005).</li><li>Gang, L., 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=Metal-free+methylation+of+a+pyridine+N-oxide+C-H+bond+by+using+peroxides.">Metal-free methylation of a pyridine N-oxide C-H bond by using peroxides.</a> Org. Biomol. Chem. 13 (46), 11184-11188 (2015).</li><li>May, D., Nyman, M. J., Hampden-Smith, E. N., Duesler, <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+reactivity+of+group+12+metal+thiocarboxylates+M(SOCR)2Lut2[M)+Cd,+Zn;+R+)+CH3,+C(CH3)3;+Lut+)+3,5-Dimethylpyridine+(Lutidine)].">Synthesis, characterization, and reactivity of group 12 metal thiocarboxylates M(SOCR)2Lut2[M) Cd, Zn; R ) CH3, C(CH3)3; Lut ) 3,5-Dimethylpyridine (Lutidine)].</a> Inorg. Chem. 36 (10), 2218-2224 (1997).</li><li>Cho, S. H., Hwang, S. J., Chang, S. <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+C-H+Functionalization+of+Pyridine+N-Oxides:+Highly+Selective+Alkenylation+and+Direct+Arylation+with+Unactivated+Arenes.">Palladium-Catalyzed C-H Functionalization of Pyridine N-Oxides: Highly Selective Alkenylation and Direct Arylation with Unactivated Arenes.</a> J. Am. Chem. Soc. 130 (29), 9254-9256 (2008).</li><li>Ide, Y., 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=Spin-crossover+between+high-spin+(S+=+5/2)+and+low-spin+(S+=+1/2)+states+in+six-coordinate+iron(III)+porphyrin+complexes+having+two+pyridine-N.+oxide+derivatives.">Spin-crossover between high-spin (S = 5/2) and low-spin (S = 1/2) states in six-coordinate iron(III) porphyrin complexes having two pyridine-N. oxide derivatives.</a> Dalton Trans. 46 (1), 242-249 (2017).</li><li>Drago, R. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Physical Methods in Chemistry. , 750 (1977).</li><li>Cervantes-Mej&#237;a, V., 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=Branched+Polyamines+Functionalized+with+Proposed+Reaction+Pathways+Based+on+1H-NMR,+Atomic+Absorption+and+IR+Spectroscopies.">Branched Polyamines Functionalized with Proposed Reaction Pathways Based on 1H-NMR, Atomic Absorption and IR Spectroscopies.</a> American Journal of Analytical Chemistry. 5 (16), 1090-1101 (2014).</li><li>Huheey, J. E., Keiter, E. A., Keiter, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Inorganic Chemistry: Principles of Structure and Reactivity, 4th Edition. , 1023 (1997).</li><li>Rigaku, <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> CrysAlisPRO. , (2013).</li><li>Sheldrick, G. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=SHELXT+-+Integrated+space-group+and+crystal-structure+determination.">SHELXT - Integrated space-group and crystal-structure determination.</a> Acta Cryst. 71 (1), 3-8 (2015).</li><li>Sheldrick, G. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Crystal+structure+refinement+with+SHELXL.">Crystal structure refinement with SHELXL.</a> Acta Cryst. 71 (1), 3-8 (2015).</li><li>Sheldrick, G. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+short+history+of+SHELX.">A short history of SHELX.</a> Acta Cryst. 64 (1), 112-122 (2008).</li><li>Macrae, C. F., 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=Mercury+CSD+2.0+-+new+features+for+the+visualization+and+investigation+of+crystal+structures.">Mercury CSD 2.0 - new features for the visualization and investigation of crystal structures.</a> J. Appl. Cryst. 41 (2), 466-470 (2008).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> ChemBioDraw Ultra 13. , (2013).</li></ol>

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ここで提示されたプロトコルは、基板上の官能基化法として 3, 5-ルチジンの窒素原子に酸素原子をリンクする従来方法です。この手法は、x 線の適切な脱水の結晶 (図 5、DSC HX300 サイバー ショット ソニーのカメラで撮影した画像) を生成する確立も。限り我々 が懸念している、ない多くのレポートは、このような結晶16の生産を説明しています。多くの化合物は...

今日では、世界中の科学者に投資しているリソース低反応性フロント付加反応1,2に知られている、芳香族グループの機能化の新しい合成ルートの開発 3。窒素原子は炭素原子を置換、ピリジンはリング3炭素原子のみで構成されるアナログに似たような反応を示し、それは通常追加ではなく、置換の機構を受けます。N-酸化物、窒素および酸素原子3空軌道を持つ窒素の非共有結合電子対の重複によって形成される酸素ドナーの絆の存在によって特徴的な。特に、ピリジンN-酸化物は、ルイス塩基、電子供与体として作用する可能性、N-O 部位と彼らは対応するルイス酸・塩基対を形成するルイス酸と組み合わせることがあります。潜在的な求電子剤に向かってルイス酸の nucleophilicity を増加できることが条件の下で反応させる、通常の反応は発生しませんので、不可欠な化学結果しております。おそらくこのような化合物の最も頻繁に使用は様々 な酸化反応酸化剤4として動作です。ピリジンN-酸化物とそのリング官能基化誘導体の多くは生物学的活性や薬理学的エージェント5、再発の分子であり、さまざまな分光学的ツールによる明確な空間分布を確立されています。それらのいくつかの6,7。ピリジン環に異なるグループを関連付けて研究の科学者はイソキサゾリン フォーム 6 - キシレンを沸騰 DBU などベースの触媒量を必要とするので、簡単で従来の方法を生成するさまざまな方法論をテストしています。置換-2-アミノピリジンN-酸化物8,9。種々 のピリジン誘導体は彼らの対応するNに変えられた-マンガン量を触媒の存在下で酸化物 tetrakis(2,6-diclorophenyl) CH2Cl2/CH3ポルフィリンおよびアンモニウムのアセテートCN8,10。CH2Cl2 methyltrioxorhenium8、11、または過剰なジメチルジオキシランの添加による触媒量の存在下で H2O2を使用して酸化物に酸化する他のピリジン0 の ° C で対応するNにつながる-酸化物8,12,13,14。ビス (トリメチルシリル) 過酸化 CH2Cl2で trioxorhenium の存在下ではピリジンNの合成使用されています-酸化物8,11。アミノピリジンNの合成-カロの酸 (peroxomonosulfuric 酸) を使用して含むアシル化もされて酸化物報告8。それにもかかわらず、ここでは、報告された方法論と落合1、によって報告された方法論の一部を使用してアクセスできる安価な試薬、H2O2氷酢酸の使用で非常に良い結果を提供します。この実習は第三級アミンに作用する大規模な準備での使用に適して、それのみ 30% 過酸化水素が必要な反応で良好な収率と 70 から 80 ° C 間の温度で氷酢酸を生成および浄化プロセスが使用触媒や高価な試薬1を使用せず、蒸留のようなほとんどの合成実験室で利用可能です。文献は、他の方法論も多く、10-24 h と温度が 100 ° C 4,8からのタイム フレームと結晶 x 線解析では収量はほとんど報告を報告します。
受身に様々 なn-酸化誘導体、適切に求核または求電子のいずれかの方法でルチジン リングをアクティブに使用されます。求または求電子的要因は、置換基の影響を受けます。主な要因は、電子グループ ピリジン環、求核特性1となっています。無料のN-酸化化合物は芳香環の非局在電荷による x 線解析に適した結晶としてほとんど分離されます。しかし、溶媒和要因は酸素15の負の密度を安定させるために重要です。

<table><tbody><tr><td>3,5-lutidine</td><td>Sigma-Aldrich</td><td>L4206-500ML</td><td></td></tr><tr><td>Glacial acetic acid</td><td>Fermont</td><td>3015</td><td></td></tr><tr><td>Hidrogen peroxide (35%)</td><td>Sigma-Aldrich</td><td>349887-500ML</td><td></td></tr><tr><td>Na&lt;sub&gt;2&lt;/sub&gt;CO&lt;sub&gt;3&lt;/sub&gt; anhydrous</td><td>Productos Qu&amp;iacute;micos Monterrey</td><td>1792</td><td></td></tr><tr><td>Na&lt;sub&gt;2&lt;/sub&gt;SO&lt;sub&gt;4&lt;/sub&gt; anhydrous</td><td>Alfa reactivos</td><td>25051-C</td><td></td></tr><tr><td>CHCl&lt;sub&gt;3&lt;/sub&gt;</td><td>Fermont</td><td>6205</td><td></td></tr><tr><td>Ethyl eter</td><td>Mercury Chemist</td><td>QME0309</td><td></td></tr><tr><td>Distilled water</td><td>Comercializadora Qu&amp;iacute;mica Poblana</td><td>not-existent</td><td></td></tr></tbody></table>

syntheses, crystallization, and spectroscopic characterization of 3,5-lutidine n-oxide dehydrate

3, 5-ルチジンN酸化物の合成は、脱水、 12-アミノ-ピリジン-3, 5-ジカルボン酸の合成ルートで達成されました。落合最初 12 h プロセスで 1957 年に非置換ピリジンの方法論に使用がない適切な結晶を x 線が得られました。ここで紹介する方法で使用される代替のリングは、 1で異なる求強度を付与する非対称単位に水分子の付加を明確に影響。X 線結晶化合物1は 2 つの水分子の存在によって酸素の負電荷の安定化により水素原子がリングに正電荷を寄付このような水の分子も超分子的相互作用を構築するサービスを提供します。水和物の分子は、10 の pH を調整することによって到達できるアルカリ用も可能です。二重メチル置換リングと 5 h の反応時間で重要なより汎用性の高い方法になりますと将来リング挿入用の広い化学。

プロトコルは、本質的に落合の技術1の拡張です。ただし、温度が低いとより少ない時間が適用されます。この単純なメソッドを使用して、置換ピリジンNである汎用性の高いリガンドを取得できます-酸化物の派生物。1の形成を確認するには、手順の有効性をテストする NMR 1H と13C 分析を優先します。
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Watch this Scientific Journal Video about Syntheses, Crystallization, and Spectroscopic Characterization of 3,5-Lutidine N-Oxide Dehydrate at JoVE.com

Syntheses, Crystallization, and Spectroscopic Characterization of 3,5-Lutidine N-Oxide Dehydrate

症例、ピリジンNの古典的な合成とは異なるシンプルなプロトコルによって脱水合成と 3, 5-ルチジンN酸化物の結晶性の酸化物。このプロトコルは異なる原料を利用し、新しい溶媒和分子構造、ゆっくりと蒸発させるの下に結晶する反応時間が含まれます。

合成、結晶化、および 3, 5-ルチジンNの分光学的キャラクタリゼーション-酸化物の脱水

The synthesis of 3,5-lutidine N-oxide dehydrate, 1, was achieved in the synthesis route of 2-amino-pyridine-3,5-dicarboxylic acid. Ochiai first used the ...

syntheses-crystallization-spectroscopic-characterization-35-lutidine

Universidad San Sebastian

Research

JoVE Journal

Chemistry

Syntheses, Crystallization, and Spectroscopic Characterization of 3,5-Lutidine N-Oxide Dehydrate

8.3K ビュー.  Benemérita Universidad Autónoma de Puebla. 症例、ピリジンNの古典的な合成とは異なるシンプルなプロトコルによって脱水合成と 3, 5-ルチジンN酸化物の結晶性の酸化物。このプロトコルは異なる原料を利用し、新しい溶媒和分子構造、ゆっくりと蒸発させるの下に結晶する反応時間が含まれます。

ビデオ: Syntheses, Crystallization, and Spectroscopic Characterization of 3,5-Lutidine N-Oxide Dehydrate

Synthesis and Characterization of Functionalized Metal-organic Frameworks

Metal-organic frameworks have attracted extraordinary amounts of research attention, as they are attractive candidates for numerous industrial and technological applications. Their signature property is their ultrahigh porosity, which however imparts a series of challenges when it comes to both constructing them and working with them. Securing desired MOF chemical and physical functionality by linker/node assembly into a highly porous framework of choice can pose difficulties, as less porous and more thermodynamically stable congeners (e.g., other crystalline polymorphs, catenated analogues) are often preferentially obtained by conventional synthesis methods. Once the desired product is obtained, its characterization often requires specialized techniques that address complications potentially arising from, for example, guest-molecule loss or preferential orientation of microcrystallites. Finally, accessing the large voids inside the MOFs for use in applications that involve gases can be problematic, as frameworks may be subject to collapse during removal of solvent molecules (remnants of solvothermal synthesis). In this paper, we describe synthesis and characterization methods routinely utilized in our lab either to solve or circumvent these issues. The methods include solvent-assisted linker exchange, powder X-ray diffraction in capillaries, and materials activation (cavity evacuation) by supercritical CO2 drying. Finally, we provide a protocol for determining a suitable pressure region for applying the Brunauer-Emmett-Teller analysis to nitrogen isotherms, so as to estimate surface area of MOFs with good accuracy.

Synthesis, activation, and characterization of intentionally designed metal-organic framework materials is challenging, especially when building blocks are incompatible or unwanted polymorphs are thermodynamically favored over desired forms. We describe how applications of solvent-assisted linker exchange, powder X-ray diffraction in capillaries and activation via supercritical CO2 drying, can address some of these challenges.

官能化有機金属構造体の合成とキャラクタリゼーション

Metal-organic frameworks have attracted extraordinary amounts of research attention, as they are attractive candidates for numerous industrial and ...

化学

Synthesis of Indoxyl-glycosides for Detection of Glycosidase Activities

Indoxyl glycosides proved to be valuable and versatile tools for monitoring glycosidase activities. Indoxyls are released by enzymatic hydrolysis and are rapidly oxidized, for example by atmospheric oxygen, to indigo type dyes. This reaction enables fast and easy screening in vivo without isolation or purification of enzymes, as well as rapid tests on agar plates or in solution (e.g., blue-white screening, micro-wells) and is used in biochemistry, histochemistry, bacteriology and molecular biology. Unfortunately the synthesis of such substrates proved to be difficult, due to various side reactions and the low reactivity of the indoxyl hydroxyl function. Especially for glucose type structures low yields were observed. Our novel approach employs indoxylic acid ester as key intermediates. Indoxylic acid esters with varied substitution patterns were prepared on scalable pathways. Phase transfer glycosylations with those acceptors and peracetylated glycosyl halides can be performed under common conditions in high yields. Ester cleavage and subsequent mild silver mediated glycosylation yields the peracetylated indoxyl glycosides in high yields. Finally deprotection is performed according to Zempl&#233;n.

Indoxyl glycosides are well-established and widely used tools for enzyme screening and enzyme activity monitoring. Especially for glucose type structures previous syntheses proved to be challenging and low yielding. Our novel approach employs indoxylic acid esters as precious intermediates to yield a considerable number of indoxyl glycosides in good yields.

グリコシダーゼ活性の検出のためのインドキシル配糖体の合成

Indoxyl glycosides proved to be valuable and versatile tools for monitoring glycosidase activities. Indoxyls are released by enzymatic hydrolysis and are ...

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.

ルテニウムのシリーズの合成、キャラクタリゼーションと反応性<em&gt; N</em&gt; -triphos<sup&gt; Phで</sup&gt;錯体

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

A Protocol for Safe Lithiation Reactions Using Organolithium Reagents

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

The safe and proper use of organolithium reagents is described.

有機リチウム試薬を用いて安全なリチウム化反応のためのプロトコル

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

One-pot Microwave-assisted Conversion of Anomeric Nitrate-esters to Trichloroacetimidates

The goal of the following procedure is to provide a demonstration of the one-pot conversion of a 2-azido-1-nitrate-ester to a trichloroacetimidate glycosyl donor. Following azido-nitration of a glycal, the product 2-azido-1-nitrate ester can be hydrolyzed under microwave-assisted irradiation. This transformation is usually achieved using strongly nucleophilic reagents and extended reaction times. Microwave irradiation induces hydrolysis, in the absence of reagents, with short reaction times. Following denitration, the intermediate anomeric alcohol is converted, in the same pot, to the corresponding 2-azido-1-trichloroacetimidate.

A 2-azido-1-nitrate-ester can be converted to the corresponding 2-azido-1-trichloroacetimidate in a one-pot procedure. The goal of the manuscript is to demonstrate utility of the microwave reactor in carbohydrate synthesis.

1 つの鍋マイクロ波への変換アノマー硝酸エステルの Trichloroacetimidates

The goal of the following procedure is to provide a demonstration of the one-pot conversion of a 2-azido-1-nitrate-ester to a trichloroacetimidate ...

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.

L リジンから光学活性アミノ アルコールの合成酵素連鎖反応

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

Regioselective O-Glycosylation of Nucleosides via the Temporary 2',3'-Diol Protection by a Boronic Ester for the Synthesis of Disaccharide Nucleosides

Disaccharide nucleosides, which consist of disaccharide and nucleobase moieties, have been known as a valuable group of natural products having multifarious bioactivities. Although chemical O-glycosylation is a commonly beneficial strategy to synthesize disaccharide nucleosides, the preparation of substrates such as glycosyl donors and acceptors requires&#160;tedious protecting&#160;group manipulations and a purification at each synthetic step. Meanwhile, several research groups have reported that boronic and borinic esters serve as a protecting or activating group of carbohydrate derivatives to achieve the regio- and/or stereoselective acylation, alkylation, silylation, and glycosylation. In this article, we demonstrate the procedure for the regioselective O-glycosylation of unprotected ribonucleosides utilizing boronic acid. The esterification of 2&#39;,3&#39;-diol of ribonucleosides with boronic acid makes the temporary protection of diol, and, following O-glycosylation with a glycosyl donor in the presence of p-toluenesulfenyl chloride and silver triflate, permits the regioselective reaction of the 5&#39;-hydroxyl group to afford the disaccharide nucleosides. This method could be applied to various nucleosides, such as guanosine, adenosine, cytidine, uridine, 5-metyluridine, and 5-fluorouridine. This article and the accompanying video represent&#160;useful (visual) information for the O-glycosylation of unprotected nucleosides and their analogs for the synthesis of not only disaccharide nucleosides, but also a variety of biologically relevant derivatives.

Regioselective O-Glycosylation of Nucleosides via the Temporary 2',3'-Diol Protection by a Boronic Ester for the Synthesis of Disaccharide Nucleosides

Here, we present protocols for the synthesis of disaccharide nucleosides by the regioselective O-glycosylation of ribonucleosides via a temporary protection of their 2&#39;,3&#39;-diol moieties utilizing a cyclic boronic ester. This method applies to several unprotected nucleosides such as adenosine, guanosine, cytidine, uridine, 5-methyluridine, and 5-fluorouridine to give corresponding disaccharide nucleosides.

ヌクレオシドを介して一時 2'、3'-ジオール保護ホウ酸エステル糖ヌクレオシドの合成のためのOの位置選択的グリコシル化反応

Disaccharide nucleosides, which consist of disaccharide and nucleobase moieties, have been known as a valuable group of natural products having ...

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of &#945;-Imino &#947;-Lactones and Alkylidene Pyrazolones

Bispirocyclic scaffolds are one of the important structural subunits in many natural products that exhibit diverse and attractive biological activities. Recently, we have developed an efficient organocatalytic strategy, which provides facile access to a variety of enantiomerically enriched bispiro[&#947;-butyrolactone-pyrrolidin-4,4&#39;-pyrazolone] skeletons. In this paper, we demonstrate a detailed protocol for the asymmetric synthesis of drug-like bispirocyclic compounds with two spirocyclic carbon centers via an organocatyltic 1,3-dipolar cycloaddition reaction. Spirocyclization synthons &#945;-imino &#947;-lactones and alkylidene pyrazolones are prepared first, which are then subjected to a cycloaddition reaction in the presence of a bifunctional squaramide organocatalyst to afford the desired bispirocycles in high yields and excellent stereoselectivities. Chiral high-performance liquid chromatography (HPLC) is carried out to determine the enantiomeric purity of the products, and the d.r. value is examined by proton nuclear magnetic resonance (1H NMR). The absolute configuration of the product is assigned according to an X-ray crystallographic analysis. This synthetic strategy allows scientists to prepare a diversity of bispirocyclic scaffolds in high yields and excellent diastereo- and enantioselectivities.

Enantiomerically enriched bispiro[&#947;-butyrolactone-pyrrolidin-4,4&#39;-pyrazolone] skeletons are asymmetrically synthesized through a simple organocatalytic 1,3-dipolar cycloaddition reaction.

効率的な薬物のような Bispirocyclic を介して α イミノ γ-ラクトンの有機触媒及び Alkylidene ピラゾロン足場の構築

Bispirocyclic scaffolds are one of the important structural subunits in many natural products that exhibit diverse and attractive biological activities. ...

A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones

We introduced a regioselective and atom-economical procedure for the synthesis of 3-substituted indoles by annulation of nitrosoarenes with ethynyl ketones. The reactions were carried out achieving indoles without any catalyst and with excellent regioselectivity. No traces of 2-aroylindole products were detected. Working with 4-nitronitrosobenzene as starting material, the 3-aroyl-N-hydroxy-5-nitroindole products precipitated from the reaction mixtures and were isolated by filtration without any further purification technique. Differently from the corresponding N-hydroxy-3-aryl indoles that, spontaneously in solution, give dehydrodimerization products, the N-hydroxy-3-aroyl indoles are stable and no dimerization compounds were observed.

A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones

3-Aroyl-N-hydroxy-5-nitroindoles were synthesized by cycloaddition of 4-nitronitrosobenzene with a conjugated terminal alkynone in a one-step thermal procedure. Preparation of the nitrosoarene and of the alkynones were adequately reported and respectively through oxidation procedures on the corresponding aniline and on the alkynol.

アルキノンスを用いた4-ニトロニトロイソベンゼンのシクロ添加による3-アロイル-N-ヒドロキシ-5-ニトロインドールの直接、レジオ選択的および原子経済的合成

We introduced a regioselective and atom-economical procedure for the synthesis of 3-substituted indoles by annulation of nitrosoarenes with ethynyl ...

Synthesis of Information-bearing Peptoids and their Sequence-directed Dynamic Covalent Self-assembly

This protocol presents the use of Lewis acidic multi-role reagents to circumvent kinetic trapping observed during the self-assembly of information-encoded oligomeric strands mediated by paired dynamic covalent interactions in a manner mimicking the thermal cycling commonly employed for the self-assembly of complementary nucleic acid sequences. Primary amine monomers bearing aldehyde and amine pendant moieties are functionalized with orthogonal protecting groups for use as dynamic covalent reactant pairs. Using a modified automated peptide synthesizer, the primary amine monomers are encoded into oligo(peptoid) strands through solid-phase submonomer synthesis. Upon purification by high-performance liquid chromatography (HPLC) and characterization by electrospray ionization mass spectrometry (ESI-MS), sequence-specific oligomers are subjected to high-loading of a Lewis acidic rare-earth metal triflate which both deprotects the aldehyde moieties and affects the reactant pair equilibrium such that strands completely dissociate. Subsequently, a fraction of the Lewis acid is extracted, enabling annealing of complementary sequence-specific strands to form information-encoded molecular ladders characterized by matrix assisted laser desorption/ionization mass spectrometry (MALDI-MS). The simple procedure outlined in this report circumvents kinetic traps commonly experienced in the field of dynamic covalent assembly and serves as a platform for the future design of robust, complex architectures.

A protocol is presented for the synthesis of information-encoded peptoid oligomers and for the sequence-directed self-assembly of these peptoids into molecular ladders using amines and aldehydes as dynamic covalent reactant pairs and Lewis acidic rare-earth metal triflates as multi-role reagents.

情報を持つペプトイドの合成と、その配列指向動的共有自己集合

This protocol presents the use of Lewis acidic multi-role reagents to circumvent kinetic trapping observed during the self-assembly of information-encoded ...

合成、結晶化、および 3, 5-ルチジンNの分光学的キャラクタリゼーション-酸化物の脱水

要約

さらに動画を探す

この動画の章

官能化有機金属構造体の合成とキャラクタリゼーション

グリコシダーゼ活性の検出のためのインドキシル配糖体の合成

ルテニウムのシリーズの合成、キャラクタリゼーションと反応性

有機リチウム試薬を用いて安全なリチウム化反応のためのプロトコル

1 つの鍋マイクロ波への変換アノマー硝酸エステルの Trichloroacetimidates

L リジンから光学活性アミノアルコールの合成酵素連鎖反応

ヌクレオシドを介して一時 2'、3'-ジオール保護ホウ酸エステル糖ヌクレオシドの合成のためのOの位置選択的グリコシル化反応

効率的な薬物のような Bispirocyclic を介して α イミノ γ-ラクトンの有機触媒及び Alkylidene ピラゾロン足場の構築

アルキノンスを用いた4-ニトロニトロイソベンゼンのシクロ添加による3-アロイル-N-ヒドロキシ-5-ニトロインドールの直接、レジオ選択的および原子経済的合成

情報を持つペプトイドの合成と、その配列指向動的共有自己集合

合成、結晶化、および 3, 5-ルチジンNの分光学的キャラクタリゼーション-酸化物の脱水

要約

さらに動画を探す

この動画の章

官能化有機金属構造体の合成とキャラクタリゼーション

グリコシダーゼ活性の検出のためのインドキシル配糖体の合成

ルテニウムのシリーズの合成、キャラクタリゼーションと反応性

有機リチウム試薬を用いて安全なリチウム化反応のためのプロトコル

1 つの鍋マイクロ波への変換アノマー硝酸エステルの Trichloroacetimidates

L リジンから光学活性アミノ アルコールの合成酵素連鎖反応

ヌクレオシドを介して一時 2'、3'-ジオール保護ホウ酸エステル糖ヌクレオシドの合成のためのOの位置選択的グリコシル化反応

効率的な薬物のような Bispirocyclic を介して α イミノ γ-ラクトンの有機触媒及び Alkylidene ピラゾロン足場の構築

アルキノンスを用いた4-ニトロニトロイソベンゼンのシクロ添加による3-アロイル-N-ヒドロキシ-5-ニトロインドールの直接、レジオ選択的および原子経済的合成

情報を持つペプトイドの合成と、その配列指向動的共有自己集合

L リジンから光学活性アミノアルコールの合成酵素連鎖反応