Name: continuous flow chemistry: reaction of diphenyldiazomethane with p-nitrobenzoic acid
Uploaded: 2017-11-15T15:00:00.000+00:00
Duration: 7 min 6 s
Description: Watch this Scientific Journal Video about Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid at JoVE.com

ברצוננו להודות קורנינג על המתנה של הכור זרימה זכוכית.

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	<li>Jimenez-Gonzalez, C., 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=Engineering+Research+Areas+for+Sustainable+Manufacturing:+A+Perspective+from+Pharmaceutical+and+Fine+Chemicals+Manufacturers.">Engineering Research Areas for Sustainable Manufacturing: A Perspective from Pharmaceutical and Fine Chemicals Manufacturers.</a> Org Process Res Dev. 15 (4), 900-911 (2011).</li><li>Constable, D. J. C., 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=Key+green+chemistry+research+areas+-+a+perspective+from+pharmaceutical+manufacturers.">Key green chemistry research areas - a perspective from pharmaceutical manufacturers.</a> Green Chem. 9 (5), 411-420 (2007).</li><li>Plutschack, M. B., Pieber, B., Gilmore, K., Seeberger, 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=The+Hitchhiker's+Guide+to+Flow+Chemistry.">The Hitchhiker's Guide to Flow Chemistry.</a> Chem Rev. , (2017).</li><li>Dallinger, D., Kappe, C. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Why+flow+means+green+-+Evaluating+the+merits+of+continuous+processing+in+the+context+of+sustainability.">Why flow means green - Evaluating the merits of continuous processing in the context of sustainability.</a> Curr Opin Green Sustain Chem. 7, 6-12 (2017).</li><li>Movsisyan, M., 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=Taming+hazardous+chemistry+by+continuous+flow+technology.">Taming hazardous chemistry by continuous flow technology.</a> Chem Soc Rev. 45 (18), 4892-4928 (2016).</li><li>Hessel, V., Ley, S. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flow+Chemistry+in+Europe.">Flow Chemistry in Europe.</a> J Flow Chem. 6 (3), 135-135 (2016).</li><li>Mascia, S., 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=End-to-End+Continuous+Manufacturing+of+Pharmaceuticals:+Integrated+Synthesis,+Purification,+and+Final+Dosage+Formation.">End-to-End Continuous Manufacturing of Pharmaceuticals: Integrated Synthesis, Purification, and Final Dosage Formation.</a> Angew Chem Int Edit. 52 (47), 12359-12363 (2013).</li><li>Newman, S. G., Jensen, K. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+flow+in+green+chemistry+and+engineering.">The role of flow in green chemistry and engineering.</a> Green Chem. 15 (6), 1456-1472 (2013).</li><li>Watts, P., Haswell, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+application+of+micro+reactors+for+organic+synthesis.">The application of micro reactors for organic synthesis.</a> Chem Soc Rev. 34 (3), 235-246 (2005).</li><li>Wiles, C., Watts, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Continuous+flow+reactors:+a+perspective.">Continuous flow reactors: a perspective.</a> Green Chem. 14 (1), 38-54 (2012).</li><li>Roberge, D. M., 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=Microreactor+technology+and+continuous+processes+in+the+fine+chemical+and+pharmaceutical+industry:+Is+the+revolution+underway.">Microreactor technology and continuous processes in the fine chemical and pharmaceutical industry: Is the revolution underway.</a> Org Process Res Dev. 12 (5), 905-910 (2008).</li><li>Degennaro, L., Carlucci, C., De Angelis, S., Luisi, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flow+Technology+for+Organometallic-Mediated+Synthesis.">Flow Technology for Organometallic-Mediated Synthesis.</a> J Flow Chem. 6 (3), 136-166 (2016).</li><li>Roberts, J. D., Watanabe, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Kinetics+and+Mechanism+of+the+Acid-Catalyzed+Reaction+of+Diphenyldiazomethane+with+Ethyl+Alcohol.">The Kinetics and Mechanism of the Acid-Catalyzed Reaction of Diphenyldiazomethane with Ethyl Alcohol.</a> J Am Chem Soc. 72 (11), 4869-4879 (1950).</li><li>Roberts, J. D., Watanabe, W., Mcmahon, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Kinetics+and+Mechanism+of+the+Reaction+of+Diphenyldiazomethane+and+Benzoic+Acid+in+Ethanol.">The Kinetics and Mechanism of the Reaction of Diphenyldiazomethane and Benzoic Acid in Ethanol.</a> J Am Chem Soc. 73 (2), 760-765 (1951).</li><li>Roberts, J. D., Watanabe, W., Mcmahon, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Kinetics+and+Mechanism+of+the+Reaction+of+Diphenyldiazomethane+with+2,4-Dinitrophenol+in+Ethanol.">The Kinetics and Mechanism of the Reaction of Diphenyldiazomethane with 2,4-Dinitrophenol in Ethanol.</a> J Am Chem Soc. 73 (6), 2521-2523 (1951).</li><li>Roberts, J. D., Regan, C. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kinetics+and+Some+Hydrogen+Isotope+Effects+of+the+Reaction+of+Diphenyldiazomethane+with+Acetic+Acid+in+Ethanol.">Kinetics and Some Hydrogen Isotope Effects of the Reaction of Diphenyldiazomethane with Acetic Acid in Ethanol.</a> J Am Chem Soc. 74 (14), 3695-3696 (1952).</li><li>Oferrall, R. A., Kwok, W. K., Miller, S. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Medium+Effects+Isotope+Rate+Factors+++Mechanism+of+Reaction+of+Diphenyldiazomethane+with+Carboxylic+Acids+in+Solvents+Ethanol+++Toluene.">Medium Effects Isotope Rate Factors + Mechanism of Reaction of Diphenyldiazomethane with Carboxylic Acids in Solvents Ethanol + Toluene.</a> J Am Chem Soc. 86 (24), 5553 (1964).</li><li>Aldrich, 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> Material Safety Data Sheet: Benzophenone Hydrazone. 4.2, 3-6 (2014).</li><li>Science Lab Chemicals &amp; Laboratory Equipment. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Material Safety Data Sheet: Manganese dioxide MSDS. , (2005).</li><li>Science Lab Chemicals &amp; Laboratory Equipment. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Material Safety Data Sheet: Potassium phosphate dibasic MSDS. , 1-5 (2005).</li><li>Science Lab Chemicals &amp; Laboratory Equipment. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Material Safety Data Sheet: Methylene Chloride MSDS. , 3-5 (2005).</li><li>Smith, L. I., Howard, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diphenyldiazomethane.">Diphenyldiazomethane.</a> Org. Synth. 3 (351), (1955).</li><li>Capot Chemical Co. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Material Safety Data Sheet, diphenyldiazomethane. 2017, (2010).</li><li>Science Lab. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Material Safety Data Sheet: P-nitrobenzoic acid MSDS. , 3-5 (2005).</li><li>Science Lab Chemicals &amp; Laboratory Equipment. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Material Safety Data Sheet Ethyl Alcohol 200 proof MSDS. , (2005).</li><li>Science Lab Chemicals &amp; Laboratory Equipment. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Material Safety Data Sheet Toluene MSDS. , 4-5 (2005).</li><li>Science Lab Chemicals &amp; Laboratory Equipment. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Material Safety Data Sheet o-Xylene MSDS. , 3-5 (2005).</li><li>Zheng, 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=Cross-Coupling+between+Difluorocarbene+and+Carbene-Derived+Intermediates+Generated+from+Diazocompounds+for+the+Synthesis+of+gem-Difluoroolefins.">Cross-Coupling between Difluorocarbene and Carbene-Derived Intermediates Generated from Diazocompounds for the Synthesis of gem-Difluoroolefins.</a> Organic Letters. 17, 6150-6153 (2015).</li><li>Reimlinger, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=1,5-Dipolar+cyclizations,+I.+Definition+and+contributions+to+the+Imidazide/Tetrazole+tautomerism.">1,5-Dipolar cyclizations, I. Definition and contributions to the Imidazide/Tetrazole tautomerism.</a> Chem. Ber. 103, 1900 (1970).</li><li>Baumann, M., Garcia, A. M. R., Baxendale, I. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flow+synthesis+of+ethyl+isocyanoacetate+enabling+the+telescoped+synthesis+of+1,2,4-triazoles+and+pyrrolo-[1,2-c]+pyrimidines.">Flow synthesis of ethyl isocyanoacetate enabling the telescoped synthesis of 1,2,4-triazoles and pyrrolo-[1,2-c] pyrimidines.</a> Org Biomol Chem. 13 (14), 4231-4239 (2015).</li><li>Baumann, M., Baxendale, I. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+synthesis+of+active+pharmaceutical+ingredients+(APIs)+using+continuous+flow+chemistry.">The synthesis of active pharmaceutical ingredients (APIs) using continuous flow chemistry.</a> Beilstein J Org Chem. 11, 1194-1219 (2015).</li><li>Pastre, J. C., Browne, D. L., Ley, S. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flow+chemistry+syntheses+of+natural+products.">Flow chemistry syntheses of natural products.</a> Chem Soc Rev. 42 (23), 8849-8869 (2013).</li><li>Pirotte, G., 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=Continuous+Flow+Polymer+Synthesis+toward+Reproducible+Large-Scale+Production+for+Efficient+Bulk+Heterojunction+Organic+Solar+Cells.">Continuous Flow Polymer Synthesis toward Reproducible Large-Scale Production for Efficient Bulk Heterojunction Organic Solar Cells.</a> Chemsuschem. 8 (19), 3228-3233 (2015).</li><li>Kumar, 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=Continuous-Flow+Synthesis+of+Regioregular+Poly(3-Hexylthiophene):+Ultrafast+Polymerization+with+High+Throughput+and+Low+Polydispersity+Index.">Continuous-Flow Synthesis of Regioregular Poly(3-Hexylthiophene): Ultrafast Polymerization with High Throughput and Low Polydispersity Index.</a> J Flow Chem. 4 (4), 206-210 (2014).</li><li>Helgesen, M., 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=Making+Ends+Meet:+Flow+Synthesis+as+the+Answer+to+Reproducible+High-Performance+Conjugated+Polymers+on+the+Scale+that+Roll-to-Roll+Processing+Demands.">Making Ends Meet: Flow Synthesis as the Answer to Reproducible High-Performance Conjugated Polymers on the Scale that Roll-to-Roll Processing Demands.</a> Adv Energy Mater. 5 (9), 1401996 (2015).</li><li>Grenier, 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=Electroactive+and+Photoactive+Poly[lsoindigo-alt-EDOT]+Synthesized+Using+Direct+(Hetero)Arylation+Polymerization+in+Batch+and+in+Continuous+Flow.">Electroactive and Photoactive Poly[lsoindigo-alt-EDOT] Synthesized Using Direct (Hetero)Arylation Polymerization in Batch and in Continuous Flow.</a> Chem Mater. 27 (6), 2137-2143 (2015).</li><li>Pollet, P., 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=Production+of+(S)-1-Benzyl-3-diazo-2-oxopropylcarbamic+Acid+tert-Butyl+Ester,+a+Diazoketone+Pharmaceutical+Intermediate,+Employing+a+Small+Scale+Continuous+Reactor.">Production of (S)-1-Benzyl-3-diazo-2-oxopropylcarbamic Acid tert-Butyl Ester, a Diazoketone Pharmaceutical Intermediate, Employing a Small Scale Continuous Reactor.</a> Ind Eng Chem Res. 48 (15), 7032-7036 (2009).</li><li>Flack, K., 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=Al(OtBu)(3)+as+an+Effective+Catalyst+for+the+Enhancement+of+Meerwein-Ponndorf-Verley+(MPV)+Reductions.">Al(OtBu)(3) as an Effective Catalyst for the Enhancement of Meerwein-Ponndorf-Verley (MPV) Reductions.</a> Org Process Res Dev. 16 (3), 1301-1306 (2012).</li><li>Aponte-Guzman, 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=A+Tandem,+Bicatalytic+Continuous+Flow+Cyclopropanation-Homo-Nazarov-Type+Cyclization.">A Tandem, Bicatalytic Continuous Flow Cyclopropanation-Homo-Nazarov-Type Cyclization.</a> Ind Eng Chem Res. 54 (39), 9550-9558 (2015).</li><li>Liotta, C. 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=Synthetic+Transformations+Employing+Continuous+Flow.">Synthetic Transformations Employing Continuous Flow.</a> ACS- Fall 2013.Synthetic Transformations Employing Continuous Flow. , (2013).</li></ol>

אף אחד המחברים בתוך פרוטוקול זה יש לכל אינטרסים כלכליים מתחרים או ניגוד עניינים.

כימיה זרימה צברה הרבה תשומת לב לאחרונה עם ממוצע של-1,500 פרסומים בנושא מדי שנה באזורים מחקר של כימיה (29%), הנדסה (25%). תהליכים מוצלחים רבים נערכו בזרימה. במקרים רבים, זרימה כימיה הודגם להפגין ביצועים מעולה כדי אצווה עבור יישומים רבים כגון ההכנות של30,החומרים הפעילים הם<sup class="xre...

כימיה ירוקה והנדסה יוצרים שינוי תרבות על הכיוון העתידי של תעשיית1,2,3,4. יש כבר מזוהה אינסטרומנטלי יתרונות סביבתיים וכלכליים מינוף ערבוב מפואר, מעבר חום, וחיסכון בעלויות דרך האסטרטגיה "קנה את" לעומת "קנה את" המסורתית5 בטכנולוגיית זרימה רציפה , 6 , 7 , 8 , 9 , 10.
למרות המשק לייצר מוצרים בעלי ערך גבוה כמו תעשיית התרופות יש זמן העדיף עיבוד אצווה, היתרונות של טכנולוגיית זרימת הפכו אטרקטיביים בשל הרכבה תחרות כלכלית והטבות הפקה מסחרית 11. לדוגמה, כאשר אולם שינוי קנה המידה אצווה מעבד, טייס סולם יחידות חייב להיות בנתה ומופעל לאמת חום מדויק ומנגנונים העברה המונית. זה בקושי בת קיימא, מפחית באופן משמעותי מחייו פטנטים סחירים של המוצר. לעומת זאת, עיבוד זרימה רציפה מאפשרת היתרונות של סולם החוצה, ומבטל את שלב הפיילוט-צמח וההנדסה הקשורים ייצור בקנה מידה-a משמעותי פיננסיים תמריץ. מעבר ההשפעה הכלכלית, טכנולוגיה רציפה מאפשרת גם אטומי ותהליכים אנרגיה יעילה. למשל, ערבוב משופרת משפר העברת מסה עבור מערכות biphasic, המוביל התשואות משופרת, אסטרטגיות שחזור זרז, ערכות מיחזור עוקבות. בנוסף, היכולת לשלוט במדויק את טמפרטורת התגובה מוביל שליטה מדויקת של התגובה קינטיקה והמוצר הפצה12. הפקד תהליך משופרת, איכות המוצר (מוצר סלקטיביות) ועל הפארמצבטית הן מאריכות הן לפרקליטים סביבתית וכלכלית.
זרימה כורים זמינים מסחרית עם מגוון רחב של גדלים ועיצובים. בנוסף, התאמה אישית של כורים לצרכים תהליך יכול בקלות להיות מושגת. במסמך זה, אנחנו מדווחים על הניסויים שנערכו כור זרימה רציפה זכוכית (איור 1). ההרכבה של מזערים (161 מ מ x 131 מ מ x 8 מ מ) עשוי זכוכית תואם עם מגוון רחב של כימיקלים, ממיסים והוא עמידים בפני קורוזיה בטווח רחב של טמפרטורות (--25 – 200 ° C), לחצים (עד 18 בר). את מזערים ובפיזור תוכננו עבור הזרקה רב, ביצועים גבוהים ערבוב זמן גמיש מגורים, מעבר חום מדויק. כל מזערים הינם מצוידים עם שתי שכבות fluidic (--25 – 200 ° C, עד 3 בר) להחלפת חום משני צדדיו של השכבה התגובה. שיעורי העברת חום הינם יחסי חום העברת שטח הפנים ביחס הפוך ל הנפח שלה. לכן, אלה מזערים להקל יחס השטח לבנפח האופטימלי עבור העברת החום משופרת. ישנם שני סוגים של מזערים (קרי מודולים): "ערבוב" ומודולים "לינארי" (איור 2). המודולים בצורת לב "ערבוב" נועדו לגרום מערבולת ולמקסם את ערבוב. לעומת זאת, המודולים ליניארי לספק זמן מגורים נוספים.
כמו הוכחת הרעיון, בחרנו את תגובת היטב תיאר diphenyldiazomethane עם חומצות קרבוקסילית13,14,15,16,17. ערכת התגובה מוצג באיור3. ההעברה הראשונית של הפרוטון מן חומצה קרבוקסילית כדי diphenyldiazomethane איטי והוא שלב קביעת קצב. השלב השני הוא מהירה, מניב את התגובה המוצר ואת החנקן. התגובה נחקר בתחילה כדי להשוות החומציות היחסית של חומצות אורגניות קרבוקסילית ב הממס האורגני (aprotic ו- protic). התגובה הוא מסדר ראשון ב- diphenyldiazomethane מסדר ראשון בחומצות קרבוקסילית.
השפעול, התגובה נערכה בנוכחותו של עודף גדול של חומצה קרבוקסילית (המקבילים טוחנת 10). כתוצאה מכך, שיעור היה מסדר ראשון פסאודו ביחס diphenyldiazomethane. קבוע קצב השני סדר ואז ניתן להשיג על-ידי חלוקת הקבוע קצב השפעול שהושג פסאודו הסדר הראשון על ידי הריכוז ההתחלתי של חומצה קרבוקסילית. בתחילה, התגובה של diphenyldiazomethane עם חומצה בנזואית (pKa = 4.2) נחקר. אצווה, התגובה הופיעה יחסית איטי, להגיע כ-90% המרה ב- 96 דקות. כמו בין קצב התגובה הוא ביחס ישר החומציות של חומצה קרבוקסילית, בחרנו כשותף התגובה של חומצה קרבוקסילית חומצי יותר, p- nitrobenzoic חומצה (pKa = 3.4) כדי לקצר את זמן התגובה. התגובה של חומצה - nitrobenzoic pעם diphenyldiazomethane באתנול נטול מים נחקר ובכך אצווה ו זרימה (איור 4). התוצאות הינם מסופקים בפירוט בסעיף הבא.
כאשר התגובה מתבצעת אתנול, שלושה מוצרים יכול להיווצר: (i) benzhydryl-4-nitrobenzoate, הנובעת התגובה של חומצה p- nitrobenzoic עם diphenylmethane קטיוני ביניים; (ii) סם אתיל benzhydryl המתקבל מתגובה של הממס, אתנול, עם קטיוני diphenylmethane; חנקן (iii). התפלגות המוצר לא נבדק כמו זה מתועד היטב בספרות; די לנו ממוקד תשומת הלב שלנו בהעברת טכנולוגיה התגובה אצווה זרימה רציפה13,14,15. השפעול להיעלמות diphenyldiazomethane היה פיקוח. התגובה ממשיך עם שינוי צבעים חיים, אשר יכול להיות שנצפו מבחינה חזותית על-ידי UV-Vis ספקטרוסקופיה. זה נובע מן העובדה כי diphenyldiazomethane היא תרכובת סגול חזק בעוד כל מוצרים אחרים מן התגובה השקופה. לכן, התגובה יכולה להיות מנוטרים באופן חזותי על בסיס איכותי ואחריו באופן כמותי UV ספקטרוסקופיה (קרי היעלמותו של הספיגה diazomethane diphenyl-525 ננומטר). במסמך זה, קודם מדווחים התגובה של חומצה - nitrobenzoic diphenyldiazomethane ו- pאתנול אצווה כפונקציה של הזמן. שנית, התגובה הייתה בהצלחה הועבר והוצאה לפועל לתוך הכור זרימה זכוכית. ההתקדמות של התגובה היה לקביעה על-ידי ניטור היעלמותו של diphenyldiazomethane באמצעות UV-ספקטרוסקופיה (במצבים האצווה וזרימה).

<table><tbody><tr><td>Thermometer</td><td>HB-USA/ Enviro-safe</td><td></td><td>Any other instrument scientific company provider works</td></tr><tr><td>Benzophenone hydrazone</td><td>Sigma-Aldrich</td><td></td><td>Store at 2-8 &amp;deg;C, 96% purity</td></tr><tr><td>Activated MnO&lt;span class=&quot;font6&quot;&gt;&lt;sub&gt;2&lt;/sub&gt;&lt;/span&gt;</td><td>Fluka</td><td></td><td>&amp;ge; 90% purity, harmful if inhaled or swallowed. Refer to MSDS for more safety precautions</td></tr><tr><td>Dibasic KH&lt;sub&gt;2&lt;/sub&gt;PO&lt;sub&gt;4&lt;/sub&gt;</td><td>Sigma-Aldrich</td><td></td><td>Serious eye damage, respiratory irritant. Refer to MSDS for more safety precautions</td></tr><tr><td>Dichloromethane (DCM)</td><td>Alfa Aesar</td><td></td><td>&amp;ge; 99.7% purity, argon packed</td></tr><tr><td>Rotovap</td><td>B&amp;uuml;chi</td><td></td><td>accessory parts include Welch self-cleaning dry vacuum model 2027, and Neuberger KNP dry ice trap&amp;nbsp;</td></tr><tr><td>Bump trap</td><td>Chemglass</td><td></td><td>Any other instrument scientific company provider works&amp;nbsp;</td></tr><tr><td>Neutral Silica Gel (50-200 mM)</td><td>Acros Organic/ Sorbent Technology</td><td></td><td>Respiratory irritant if inhaled, refer to MSDS for more safety precautions</td></tr><tr><td>Inert Argon Gas</td><td>Airgas</td><td></td><td>Always ensure proper regulator is in place before using</td></tr><tr><td>Medium Porosity Sintered Funnel Glass Filter</td><td>Sigma-Aldrich</td><td></td><td>Any other instrument scientific company provider works</td></tr><tr><td>Aluminum Foil</td><td>Reynolds Wrap</td><td></td><td>Any other company works. Used to prevent photolytic damage towards DDM</td></tr><tr><td>Para-NO&lt;sub&gt;2&lt;/sub&gt; benzoic acid</td><td>Sigma-Aldrich</td><td></td><td>Skin contact irritant, eye irritant, respiratory irritant. Refer to MSDS for more safety precautions</td></tr><tr><td>Pure ethyl alcohol (200 proof)</td><td>Sigma-Aldrich</td><td></td><td>&amp;ge; 99.5% purity, anhydrous. Highly flammable</td></tr><tr><td>Toluene</td><td>Sigma-Aldrich</td><td></td><td>&amp;ge; 99.8% purity, anhydrous. Skin permeator, flammable</td></tr><tr><td>Ortho-xylene</td><td>Sigma-Aldrich</td><td></td><td>99% purity, anhydrous. Toxic to organs and CNS. Adhere to specifications dictated within MSDS</td></tr><tr><td>Diphenyl diazo methane</td><td>Produced in-house</td><td></td><td>Respiratory irritant, refer to MSDS for more safety precautions</td></tr><tr><td>Corning reactor</td><td>Corning Proprietary</td><td></td><td>Manufactured in 2009. model number MR 09-083-1A</td></tr><tr><td>Stop watch</td><td>Traceable Calibration Control Company</td><td></td><td>Any other company that provides monitoring with laboratory grade accredidation works</td></tr><tr><td>Analytical balance</td><td>Denver Instruments</td><td></td><td>Model M-2201, or any analytical balance that has sub-milligram capabilities</td></tr><tr><td>Dram vials</td><td>VWR</td><td></td><td>2 dram, 4 dram, and 6 dram vials&amp;nbsp;</td></tr><tr><td>Micropipettes</td><td>Eppendorf</td><td></td><td>2-20 &amp;mu;L and 100-1000 &amp;mu;L micropipettes work</td></tr><tr><td>Glass pipettes</td><td>VWR</td><td></td><td>Any other instrument scientific company provider works</td></tr><tr><td>GC-MS</td><td>Shimadzu GC</td><td></td><td>Software associated: GC Real Time Analysis</td></tr><tr><td>GC vials</td><td>VWR</td><td></td><td>Any other providing company works</td></tr><tr><td>Beakers</td><td>Pyrex</td><td></td><td>500 mL beakers&amp;nbsp;</td></tr><tr><td>Syringe pumps</td><td>Sigma Aldrich</td><td></td><td>Teledyne Isco Model 500D</td></tr><tr><td>Relief valve</td><td>Swagelok</td><td></td><td>Spring loaded relieve valve&amp;nbsp;</td></tr><tr><td>One-way valves</td><td>Nupro&amp;nbsp;</td><td></td><td>10 psi grade</td></tr><tr><td>Two-way straight valves</td><td>HiP</td><td></td><td>15,000 psi grade</td></tr></tbody></table>

continuous flow chemistry: reaction of diphenyldiazomethane with p-nitrobenzoic acid

זרימה רציפה הטכנולוגיה כבר זיהתה. פלייבקים שלו סביבתי, כלכלי יתרונות סופריור למינוף ערבוב, מעבר חום וחיסכון בעלויות דרך האסטרטגיה "קנה את" בניגוד המסורתי "קנה את". במסמך זה, אנו מדווחים על התגובה של diphenyldiazomethane עם p- nitrobenzoic חומצה במצבים האצווה וזרימה. כדי להעביר ביעילות את התגובה מאצווה למצב זרימה, זה חיוני כדי התנהגות הראשונה התגובה אצווה. כתוצאה מכך, התגובה של diphenyldiazomethane נחקר לראשונה אצווה כפונקציה של הטמפרטורה, זמן התגובה, וריכוז כדי להשיג מידע קינטי ולעבד פרמטרים. זכוכית זרימה הכור מתואר הקמה משלב שני סוגים של מודולים התגובה עם "ערבוב" מזערים "לינארי". לבסוף, התגובה של diphenyldiazomethane עם p- nitrobenzoic חומצה נערכה בהצלחה לכור זרימה, עם עד 95% המרה של diphenyldiazomethane ב- 11 דקות. הוכחה קונספט התגובה שואפת לספק תובנה עבור המדענים לשקול את התחרותיות של זרימה הטכנולוגיה, הקיימות ואת צדדיות במחקר שלהם.

התגובה אצווה Diphenyldiazomethane הוכן על-פי הספרות28,29. המתחם היה גיבש של נפט אתר: אתיל אצטט (100:2), בבית מוצק גבישי סגול נותחה על ידי H1 NMR, נקודת התכה ו- MS. הבדיקות היו בקנה אחד עם המבנה ודיווח ספרות ערכים.
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Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid

כימיה זרימה נושא איכות הסביבה, יתרונות כלכליים באמצעות מינוף ערבוב מפואר, מעבר חום ועלות תועלת. במסמך זה, אנו מספקים תוכנית כדי להעביר תהליכים כימיים אצווה מצב זרימה. התגובה של diphenyldiazomethane (DDM) עם p- nitrobenzoic חומצה, מתנהל ב אצווה, זרימה, נבחרה עבור הוכחת הרעיון.

זרימה רציפה כימיה: התגובה של Diphenyldiazomethane עם חומצה - Nitrobenzoic p

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Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid

Unit 1

Carboxylic Acids

Chemical Kinetics

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11.4K Views.  Georgia Institute of Technology. כימיה זרימה נושא איכות הסביבה, יתרונות כלכליים באמצעות מינוף ערבוב מפואר, מעבר חום ועלות תועלת. במסמך זה, אנו מספקים תוכנית כדי להעביר תהליכים כימיים אצווה מצב זרימה. התגובה של diphenyldiazomethane (DDM) עם p- nitrobenzoic חומצה, מתנהל ב אצווה, זרימה, נבחרה עבור הוכחת הרעיון.

Video: Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid

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.

תגובות חוצה צימוד Mizoroki-לעזאזל האיצו ידי dichloro {bis [1,1 &#39;, 1&#39;&#39; - tripiperidine (phosphinetriyl)]} פלדיום בתנאי תגובה מתון

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 ...

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization

We demonstrate a method for high-throughput catalyst screening using a parallel pressure reactor starting from the initial synthesis of a nickel &#945;-diimine ethylene polymerization catalyst. Initial polymerizations with the catalyst lead to optimized reaction conditions, including catalyst concentration, ethylene pressure and reaction time. Using gas-uptake data for these reactions, a procedure to calculate the initial rate of propagation (kp) is presented. Using the optimized conditions, the ability of the nickel &#945;-diimine polymerization catalyst to undergo chain transfer with diethylzinc (ZnEt2) during ethylene polymerization was investigated. A procedure to assess the ability of the catalyst to undergo chain transfer (from molecular weight and 13C NMR data), calculate the degree of chain transfer, and calculate chain transfer rates (ke) is presented.

A protocol for the high-throughput analysis of polymerization catalyst, chain transfer polymerizations, polyethylene characterization, and reaction kinetic analysis is presented.

Polymerizations אתילן באמצעות כורי לחץ מקבילים וניתוח קינטי של העברת פלמור שרשרת

We demonstrate a method for high-throughput catalyst screening using a parallel pressure reactor starting from the initial synthesis of a nickel ...

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

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

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

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

פלדיום<em&gt; N</em&gt; קומפלקסים Carbene heterocyclic: סינתזה מ Benzimidazolium מלחים ופעילות קטליטי פחמן פחמן בונד התגבשות התגובות

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

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles

Bicyclic aziridinium ions were generated by the removal of an appropriate leaving group through internal nucleophilic attack by nitrogen atom in the aziridine ring. The utility of bicyclic aziridinium ions, specifically 1-azoniabicyclo[3.1.0]hexane and 1-azoniabicyclo[4.1.0]heptane tosylate highlighted in the aziridine ring openings by the nucleophile with the release of the ring strain to yield the corresponding ring-expanded azaheterocycles such as pyrrolidine, piperidine and azepane with diverse substituents on the ring in regio- and stereospecific manner. Herein, we report a simple and convenient method for the preparation of the stable 1-azabicyclo[4.1.0]heptane tosylate followed by selective ring opening via a nucleophilic attack either at the bridge or at the bridgehead carbon to yield piperidine and azepane rings, respectively. This synthetic strategy allowed us to prepare biologically active natural products containing piperidine and azepane motif including sedamine, allosedamine, fagomine and balanol in highly efficient manner.

Bicyclic aziridinium ions such as 1-azoniabicyclo[4.1.0]heptane tosylate were generated from 2-[4-tolenesulfonyloxybutyl]aziridine, which was utilized for the preparation of substituted piperidines and azepanes via regio- and stereospecific ring-expansion with various nucleophiles. This highly efficient protocol allowed us to prepare diverse azaheterocycles including natural products such as fagomine, febrifugine analogue and balanol.

הכנת יציב Aziridinium Bicyclic יונים, פתיחת הטבעת שלהם לסינתזה של Azaheterocycles

Bicyclic aziridinium ions were generated by the removal of an appropriate leaving group through internal nucleophilic attack by nitrogen atom in the ...

[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst

Our group recently reported the use of [(DPEPhos)(bcp)Cu]PF6 as a general copper-based photoredox catalyst which proved efficient to promote the activation of a broad variety of organic halides, including unactivated ones. These can then participate in various radical transformations such as reduction and cyclization reactions, as well as in the direct arylation of several (hetero)arenes. These transformations provide a straightforward access to a range of small molecules of interest in synthetic chemistry, as well as to biologically active natural products. Altogether, [(DPEPhos)(bcp)Cu]PF6 acts as a convenient photoredox catalyst which appears to be an attractive, cheap and complementary alternative to the state-of-the-art iridium- and ruthenium-based photoredox catalysts. Here, we report a detailed protocol for the synthesis of [(DPEPhos)(bcp)Cu]PF6, as well as NMR and spectroscopic characterizations, and we illustrate its use in synthetic chemistry for the direct arylation of (hetero)arenes and radical cyclization of organic halides. In particular, the direct arylation of N-methylpyrrole with 4-iodobenzonitrile to afford&#160;4-(1-methyl-1H-pyrrol-2-yl)benzonitrile and the radical cyclization of N-benzoyl-N-[(2-iodoquinolin-3-yl)methyl]cyanamide to afford natural product luotonin A are detailed. The scope and limitations of this copper-based photoredox catalyst are also briefly discussed.

[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst

Detailed and general protocols are presented for the synthesis of [(DPEPhos)(bcp)Cu]PF6, a general copper-based photoredox catalyst, and for its use in synthetic chemistry for the direct arylation of C-H bonds in (hetero)arenes and radical cyclization of organic halides.

(Bcp). PF6: זרז המבוסס על נחושת מבוסס-על-ידי כללי וכללית

Our group recently reported the use of [(DPEPhos)(bcp)Cu]PF6 as a general copper-based photoredox catalyst which proved efficient to promote the ...

A Scalable Balz-Schiemann Reaction Protocol in a Continuous Flow Reactor

The demand for aromatic fluorides is steadily increasing in the pharmaceutical and fine chemical industries. The Balz-Schiemann reaction is a straightforward strategy for preparing aryl fluorides from aryl amines, via the preparation and conversion of diazonium tetrafluoroborate intermediates. However, significant safety risks exist in handling the aryl diazonium salts when scaling up. In order to minimize the hazard, we present a continuous flow protocol that has been successfully performed at a kilogram scale that eliminates the isolation of aryl diazonium salts while facilitating efficient fluorination. The diazotization process was performed at 10 &#176;C with a residence time of 10 min, followed by a fluorination process at 60 &#176;C with a residence time of 5.4 s with about 70% yield. The reaction time has been dramatically reduced by introducing this multi-step continuous flow system.

A detailed scalable continuous flow protocol is presented to synthesize an aryl fluoride from an aryl amine through the Balz-Schiemann reaction.

פרוטוקול תגובת בלז-שיימן הניתן להרחבה בכור זרימה רציפה

The demand for aromatic fluorides is steadily increasing in the pharmaceutical and fine chemical industries. The Balz-Schiemann reaction is a ...

Molecular Orbital (MO) Theory

Source: Tamara M. Powers, Department of Chemistry, Texas A&#38;M University
This protocol serves as a guide in the synthesis of two metal complexes featuring the ligand 1,1&#39;-bis(diphenylphosphino)ferrocene (dppf): M(dppf)Cl2, where M = Ni or Pd. While both of these transition metal complexes are 4-coordinate, they exhibit different geometries at the metal center. Using molecular orbital (MO) theory in conjunction with 1H NMR and Evans method, we will determine the geometry of these two compounds.

Molecular Orbital MO Theory: Predicting Geometry of Transition Metal Complexes

תורת מסלולית מולקולרית (MO)

Source: Tamara M. Powers, Department of Chemistry, Texas A&#38;M University
This protocol serves as a guide in the synthesis of two metal complexes ...

JoVE Science Education

Inorganic Chemistry

Carboxylic Acids to Methylesters: Alkylation using Diazomethane

Carboxylic acids react with diazomethane in an ether solvent via alkylation at the carboxylate oxygen atom to give methyl esters of the corresponding acid with excellent yields.
<img alt="Esterification reaction: carboxylic acid with diazomethane formula, chemical process diagram." src="/files/ftp_upload/12349/12349_PT_Figure_1.svg" style="text-align: center; height: 60px;" data-altupdatedat="1747908711000" data-alt="Figure1">
Diazomethane is a yellow gas having a boiling point of −23 °C. It is conveniently prepared by the action of a base on N-methyl-N-nitrosourea or N-methyl-N-nitrosotoluenesulphonamide.
The esterification mechanism involves the protonation of diazomethane by the carboxylic acid to yield a carboxylate salt and methyldiazonium cation. The methyldiazonium cation is highly unstable due to the presence of N≡N, which functions as an excellent leaving group.
<img alt="Chemical reaction, Curtius rearrangement equations, molecular transformation diagram." src="/files/ftp_upload/12349/12349_PT_Figure_2.svg" style="text-align: center; height: 72px;" data-altupdatedat="1747908711000" data-alt="Figure2">
In the final alkylation step, an SN2 attack on the methyldiazonium ion by the carboxylate anion produces a methyl ester, along with the elimination of N2 gas.
<img alt="SN2 reaction mechanism diagram; nucleophile attack on carbonyl, forming new bond, expelling N2." src="/files/ftp_upload/12349/12349_PT_Figure_3.svg" style="text-align: center; height: 70px;" data-altupdatedat="1747908711000" data-alt="Figure3">
However, diazomethane is a potentially explosive gas and requires precautions during its handling and storage. It undergoes spontaneous detonation upon contact with rough or scratched surfaces. Therefore, flame-polished glassware and a blast shield are often recommended in reactions involving diazomethane. Moreover, diazomethane is highly toxic as well as carcinogenic.
Diazomethane decomposes in the presence of heat or light to generate carbenes and eliminate nitrogen.
<img alt="Chemical reaction diagram; azide decomposition to form methylene and nitrogen under heat or light." src="/files/ftp_upload/12349/12349_PT_Figure_4.svg" style="text-align: center; height: 52px;" data-altupdatedat="1747908711000" data-alt="Figure4">

חומצות קרבוקסיליות למתילאסטרים: אלקילציה באמצעות דיאזומתאן

Carboxylic acids react with diazomethane in an ether solvent&#160;via alkylation at the carboxylate oxygen atom&#160;to give&#160;methyl esters of the ...

KEY TERMS AND CONCEPTS

Hydrolysis of Chlorobenzene to Phenol: Dow Process

Simple aryl halides do not react with nucleophiles under normal conditions. However, the reaction can proceed under drastic conditions involving high temperatures and high pressure&#160;to give the substituted products. For example,&#160;chlorobenzene is converted to&#160;phenol using&#160;aqueous sodium hydroxide at 350 &#176;C&#160;under high pressure by the Dow process. The reaction follows an elimination-addition mechanism involving a benzyne intermediate. Here, the chloride ion is eliminated to generate the benzyne intermediate. The benzyne intermediate then reacts with the base, followed by&#160;an acid workup that&#160;generates phenol as the final product.

הידרוליזה של כלורובנזן לפנול: תהליך דאו

Simple aryl halides do not react with nucleophiles under normal conditions. However, the reaction can proceed under drastic conditions involving high ...

Reactions of Aromatic Compounds

Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions

Arenediazonium substitution reactions occur when the diazonium group is substituted by various functional groups such as halides, hydroxyl, nitrile, etc. For instance, arenediazonium salts react with copper(I) salts of chloride, bromide, or cyanide to form corresponding aryl chlorides, bromides, and nitriles. These reactions are named Sandmeyer reactions. Although the mechanism of this reaction is complicated, as illustrated in Figure 1, they are believed to progress via an aryl copper intermediate.
<img alt="Figure1" src="/files/ftp_upload/12539/12539-PT_Figure_1.svg" style="text-align: center; height: 275px;" />
Figure 1. The formation of aryl halides and nitriles via the Sandmeyer reaction
The hydrolysis of aryl nitriles into carboxylic acids is very facile. In this context, the Sandmeyer reaction plays a crucial role in converting aryl amines to substituted benzonitrile, as shown in Figure 2.
<img alt="Figure2" src="/files/ftp_upload/12539/12539-PT_Figure_2.svg" style="text-align: center; height: 85px;" />
Figure 2. The conversion of aryl amines to substituted benzonitrile.
Sandmeyer reactions are not used to prepare aryl fluorides and aryl iodides. For aryl fluorides, the arenediazonium salts react with fluoroboric acid to give diazonium fluoroborate in the form of a precipitated salt. As depicted in Figure 3, these residues are isolated, dried, and heated until they decompose to form the corresponding aryl fluorides. Such reactions are named Schiemann reactions. Similarly, arenediazonium salts react with potassium iodide to form aryl iodides.
<img alt="Figure3" src="/files/ftp_upload/12539/12539-PT_Figure_3.svg" style="text-align: center; height: 90px;" />
Figure 3. The formation of aryl fluoride via the Schiemann reaction.

החלפת קבוצת דיאזוניום בהלוגנים וציאניד: תגובות סנדמאייר ושימן

Arenediazonium substitution reactions occur when the diazonium group is substituted by various functional groups such as halides, hydroxyl, nitrile, etc. ...

זרימה רציפה כימיה: התגובה של Diphenyldiazomethane עם חומצה - Nitrobenzoic p

Summary

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תגובות חוצה צימוד Mizoroki-לעזאזל האיצו ידי dichloro {bis [1,1 ', 1'' - tripiperidine (phosphinetriyl)]} פלדיום בתנאי תגובה מתון