Organocatalysis

In <a href="/facts/Organic_chemistry/djxhxaNg">organic chemistry</a>, organocatalysis is a form of <a href="/facts/Catalysis/LPBS7TQC">catalysis</a> in which the rate of a <a href="/facts/Chemical_reaction/GpqWlKrz">chemical reaction</a> is increased by an <a href="/facts/Organic_compound/gqCNaN45">organic</a> catalyst. This "organocatalyst" consists of <a href="/facts/Carbon/ukrgQexo">carbon</a>, <a href="/facts/Hydrogen/BoYHjl0J">hydrogen</a>, <a href="/facts/Sulfur/IK0amTfM">sulfur</a> and other nonmetal elements found in organic compounds. Because of their similarity in composition and description, they are often mistaken as a <a href="/facts/Misnomer/P4TnsX3H">misnomer</a> for <a href="/facts/Enzyme/DSI1Fh7y">enzymes</a> due to their comparable effects on reaction rates and forms of catalysis involved.
Organocatalysts which display secondary <a href="/facts/Amine/JvfYJfP6">amine</a> functionality can be described as performing either <a href="/facts/Enamine/TaubsvCU">enamine</a> catalysis (by forming catalytic quantities of an active enamine <a href="/facts/Nucleophile/xYccoaJQ">nucleophile</a>) or <a href="/facts/Imine/yK72z07j">iminium</a> 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 <a href="/facts/Green_chemistry/7csVY28w">green chemistry</a>. In this context, simple organic acids have been used as catalyst for the modification of cellulose in water on multi-ton scale. When the organocatalyst is <a href="/facts/Chirality_(chemistry)/p5a9pftB">chiral</a> an avenue is opened to <a href="/facts/Asymmetric_catalysis/5hJe37TL">asymmetric catalysis</a>; for example, the use of <a href="/facts/Proline/x1ABSW5A">proline</a> in <a href="/facts/Aldol_reaction/L194Bx0g">aldol reactions</a> is an example of chirality and green chemistry. Organic chemists <a href="/facts/David_MacMillan/JkVMPsWM">David MacMillan</a> and <a href="/facts/Benjamin_List/PrLmJM81">Benjamin List</a> were both awarded the 2021 Nobel Prize in chemistry for their work on asymmetric organocatalysis.

Organocatalysis open-in-new

Organocatalysis