Back تحفيز عضوي Arabic Organokatalýza Czech Organokatalyse Danish Organokatalyse German Οργανοκατάλυση Greek Organocatálisis Spanish Organokatalüüs Estonian کاتالیزور آلی Persian Organokatalyysi Finnish Orgánachatalú Irish

Organocatalysis

Justus von Liebig's synthesis of oxamide from dicyan and water represents the first organocatalytic reaction, with acetaldehyde further identified as the first discovered pure "organocatalyst", which act similarly to the then-named "ferments", now known as enzymes.[1][2]

In organic chemistry, organocatalysis is a form of catalysis in which the rate of a chemical reaction is increased by an organic catalyst. This "organocatalyst" consists of carbon, hydrogen, sulfur and other nonmetal elements found in organic compounds.[3][4][5][6][7][8] Because of their similarity in composition and description, they are often mistaken as a misnomer for enzymes due to their comparable effects on reaction rates and forms of catalysis involved.

Organocatalysts which display secondary amine functionality can be described as performing either enamine catalysis (by forming catalytic quantities of an active enamine nucleophile) or iminium catalysis (by forming catalytic quantities of an activated iminium electrophile). This mechanism is typical for covalent organocatalysis. Covalent binding of substrate normally requires high catalyst loading (for proline-catalysis typically 20–30 mol%). Noncovalent interactions such as hydrogen-bonding facilitates low catalyst loadings (down to 0.001 mol%).

Organocatalysis offers several advantages. There is no need for metal-based catalysis thus making a contribution to green chemistry. In this context, simple organic acids have been used as catalyst for the modification of cellulose in water on multi-ton scale.[9] When the organocatalyst is chiral an avenue is opened to asymmetric catalysis; for example, the use of proline in aldol reactions is an example of chirality and green chemistry.[10] Organic chemists David MacMillan and Benjamin List were both awarded the 2021 Nobel Prize in chemistry for their work on asymmetric organocatalysis.[11]

  1. ^ Justus von Liebig, Justus (1860). "Ueber die Bildung des Oxamids aus Cyan". Annalen der Chemie und Pharmacie. 113 (2): 246–247. doi:10.1002/jlac.18601130213.
  2. ^ W. Langenbeck (1929). "Über organische Katalysatoren. III. Die Bildung von Oxamid aus Dicyan bei Gegenwart von Aldehyden". Liebigs Ann. 469: 16–25. doi:10.1002/jlac.19294690103.
  3. ^ Berkessel, A.; Groeger, H. (2005). Asymmetric Organocatalysis. Weinheim: Wiley-VCH. ISBN 978-3-527-30517-9.
  4. ^ Special Issue: List, Benjamin (2007). "Organocatalysis". Chem. Rev. 107 (12): 5413–5883. doi:10.1021/cr078412e.
  5. ^ Peter I. Dalko; Lionel Moisan (2004). "In the Golden Age of Organocatalysis". Angew. Chem. Int. Ed. 43 (39): 5138–5175. doi:10.1002/anie.200400650. PMID 15455437.
  6. ^ Matthew J. Gaunt; Carin C.C. Johansson; Andy McNally; Ngoc T. Vo (2007). "Enantioselective organocatalysis". Drug Discovery Today. 12 (1/2): 8–27. doi:10.1016/j.drudis.2006.11.004. PMID 17198969.
  7. ^ Dieter Enders; Christoph Grondal; Matthias R. M. Hüttl (2007). "Asymmetric Organocatalytic Domino Reactions". Angew. Chem. Int. Ed. 46 (10): 1570–1581. doi:10.1002/anie.200603129. PMID 17225236.
  8. ^ Peter I. Dalko; Lionel Moisan (2001). "Enantioselective Organocatalysis". Angew. Chem. Int. Ed. 40 (20): 3726–3748. doi:10.1002/1521-3773(20011015)40:20<3726::AID-ANIE3726>3.0.CO;2-D. PMID 11668532.
  9. ^ International Patent WO 2006068611 A1 20060629 " Direct Homogeneous and Heterogeneous Organic Acid and Amino Acid-Catalyzed Modification of Amines and Alcohols" Inventors: Armando Córdova, Stockholm, Sweden; Jonas Hafrén, Stockholm, Sweden.
  10. ^ Example 4 in U.S. Patent 3,975,440 August 17, 1976, Filed Dec. 9, 1970 Zoltan G. Hajos and David R. Parrish.
  11. ^ "2021 Nobel Prize in chemistry". Nobel Prize. Nobel Prize. Retrieved 6 October 2021.
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