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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.
An illustrative example is the effect of catalysts to speed the decomposition of hydrogen peroxide into water and oxygen: . 2 H 2 O 2 → 2 H 2 O + O 2. This reaction proceeds because the reaction products are more stable than the starting compound, but this decomposition is so slow that hydrogen peroxide solutions are commercially available.
Hydrogen-bond catalysis is a type of organocatalysis that relies on use of hydrogen bonding interactions to accelerate and control organic reactions. In biological systems, hydrogen bonding plays a key role in many enzymatic reactions, both in orienting the substrate molecules and lowering barriers to reaction. [ 1 ]
Within the area of organocatalysis, squaramide catalysis describes the use of squaramides to accelerate and stereochemically alter organic transformations. The effects arise through hydrogen-bonding interactions between the substrate and the squaramide, unlike classic catalysts, and is thus a type of hydrogen-bond catalyst.
Unsaturated NHO. An N-heterocyclic olefin (NHO) is a neutral heterocyclic compound with a highly polarized, electron-rich C=C olefin attached to a heterocycle made up of two nitrogen atoms.
Chemistry, not moral failing, accounts for the brain’s unwinding. In the laboratories that study drug addiction, researchers have found that the brain becomes conditioned by the repeated dopamine rush caused by heroin. “The brain is not designed to handle it,” said Dr. Ruben Baler, a scientist with the National Institute on Drug Abuse.
Psychology Today content and its therapist directory are found in 20 countries worldwide. [3] Psychology Today's therapist directory is the most widely used [4] and allows users to sort therapists by location, insurance, types of therapy, price, and other characteristics. It also has a Spanish-language website.
Proline organocatalysis is the use of proline as an organocatalyst in organic chemistry. This theme is often considered the starting point for the area of organocatalysis, even though early discoveries went unappreciated. [1] Modifications, such as MacMillan’s catalyst and Jorgensen's catalysts, proceed with excellent stereocontrol. [2]: 5574 [3]