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Conversion and its related terms yield and selectivity are important terms in chemical reaction engineering.They are described as ratios of how much of a reactant has reacted (X — conversion, normally between zero and one), how much of a desired product was formed (Y — yield, normally also between zero and one) and how much desired product was formed in ratio to the undesired product(s) (S ...
Chemoselectivity is the preferential reaction of a chemical reagent with one of two or more different functional groups. [1]In a chemoselective system, a reagent in the presence of an aldehyde and an ester would mostly target the aldehyde, even if it has the option to react with the ester.
Relation between chemical reaction conversion selectivity and yield. In chemical reaction engineering, "yield", "conversion" and "selectivity" are terms used to describe ratios of how much of a reactant has reacted—conversion, how much of a desired product was formed—yield, and how much desired product was formed in ratio to the undesired product—selectivity, represented as X, S, and Y.
In this context selectivity represents the ratio of reaction rates. This principle was generally accepted until the 1970s when too many exceptions started to appear. The principle is now considered obsolete. [1] A classic example of perceived RSP found in older organic chemistry textbooks concerns the free radical halogenation of simple alkanes.
Energy profile diagram for kinetic versus thermodynamic product reaction. Thermodynamic reaction control or kinetic reaction control in a chemical reaction can decide the composition in a reaction product mixture when competing pathways lead to different products and the reaction conditions influence the selectivity or stereoselectivity.
University College of Engineering & Technology, University of Sargodha; Khawaja Fareed University of Engineering and Information Technology, Rahim Yar Khan [54] Quaid-e-Azam College of Engineering and Technology, Sahiwal [55] University of South Asia, Lahore [56] Namal University, Mianwali [57] Government College University, Lahore [58]
Click chemistry is an approach to chemical synthesis that emphasizes efficiency, simplicity, selectivity, and modularity in chemical processes used to join molecular building blocks. It includes both the development and use of "click reactions", a set of simple, biocompatible chemical reactions that meet specific criteria like high yield, fast ...
The selectivity arises from differences in steric and electronic effects in the mechanistic pathways leading to the different products. Stereoselectivity can vary in degree but it can never be total since the activation energy difference between the two pathways is finite: both products are at least possible and merely differ in amount.