Wednesday, November 20, 2019

Practical Synthesis of Useful Substances Using Organocatalysts Research Paper

Practical Synthesis of Useful Substances Using Organocatalysts - Research Paper Example This makes it a more efficient process, which uses fewer chemicals in the synthesis process, making it by a far greener and less toxic process. II. Background A. The concept of organocatalysis Acceleration of chemical processes through addition of substoichiometric quantity of organic compound refers to organocatalysis. In the last few years, interest in this field has increased because of selectivity and efficiency of many organocatalytic reactions, which have met standards of the required organic reactions. Observably, organocatalytic reactions are becoming popular in constructions of complex molecules. This recent development is because the process is less toxic compared to metallic catalysts. Predominant molecules used in the organocatalytic reaction are carbon, hydrogen, nitrogen, sulphur and phosphorous (McMurry, 2009). Organocatalysts usually display secondary characteristics, which would lead to enamine catalysis or iminium catalysis. The mechanism involved is covalent organo catalysis. High catalysts loading apply in covalent binding of substrates while non-covalent bonding requires low substrate loading. Knoevenagel Condensation applies regular achiral organocatalysts, which uses nitrogen as its basis. The current focus of organocatalysis is asymmetric organocatalysis, which involves the use of chiral catalysts. Scientific reactions indicate asymmetric catalysis occurs when organocatalyst is chiral as observed in aldol reactions (McMurry, 2009). Organocatalysts have the following advantages they are less sensitive to moisture or oxygen, readily available, less toxic, and inexpensive (Berkessel, 2006). These advantages make organocatalysts preferable in pharmaceutical processes. During the chemical reactions toxin produced usually influence usage of certain chemical process. Notably, organocatalysis has less impact to the environment. The condition for the reaction is relatively mild thus making organocatalysts preferable over metal catalysts. The follo wing example illustrating Knoevenagel Condensation indicates that Piperdine forms iminium ion, which is reactive with carbonyl compound. Fig 1: Retrieved from http://www.organic-chemistry.org/topics/organocatalysis.shtm B. Definition of terms Catalyst is a chemical substance that increases the rate of a chemical reaction but does not change its chemical composition at the end of the chemical process. Organocatalyst are catalysts, which contain organic compounds. Enamine catalysts refers to a compound that forms when ketone or aldehyde react with secondary amine resulting into a loss of Water. Imine is a compound that contains carbon hydrogen double bond. Covalent bonding refers to a chemical bonding process where atoms share electrons. Covalent bonding occurs between non-metallic atoms. Chiral is a term used to describe a molecule that does not fit on its mirror image (Reetz & Joroch, 2008). Achiral refers to molecules that are identical or fit into their mirror image. Asymmetric or ganocatalysis refers to organic synthesis, which leads to introduction of desired element of chirality (Berkessel, 2006). This technology applies in pharmaceuticals since different enantiomers of molecule contain different biological components. Aldol reaction refers to a method that leads to formation of carbon-carbon bonds. Knoevenagel Condensation this refers to carbon acid compound condensation using aldehydes to produce unsaturated ? and ? compounds (Berkessel, 2006).

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