What is tautomerism?
What is tautomerism?
Tautomerism is a phenomenon in which a single chemical molecule exists in two or more interconvertible forms that differ in terms of the relative location of one atomic nucleus, usually hydrogen. Both structures are referred to as tautomers and the amount of electrons and protons for both types of molecules is generally just different. They are also dynamically balanced.
When these chemicals react, the only thing that happens is a transfer of protons. Desmotropism is another name for tautomerism. Tautomers are chemical compounds that have structural isomers (constitutional isomers) that easily interconvert. A hydrogen atom is frequently relocated as a result of this process. Tautomerism, for example, is crucial to the behaviour of amino acids and nucleic acids, two of life’s basic building components.
Tautomerism’s Structural Requirement
- Compounds have polar molecules and functional groups with weakly acidic groups.
- It entails a shift in the location of an atom.
- It has no influence on bond length or other characteristics.
- It can arise in either planar or non-planar molecules.
Tautomerism Types
Emil Erlenmeyer, a physicist, created the rule for tautomerism in the 1880s. He was among the first to investigate the keto-enol tautomerism. According to this rule, the hydroxyl group in all alcohols produces ketones or aldehydes when it is directly linked to a double-bonded carbon atom. This was attributed to the increased stability of the keto form.
There are several forms of tautomerism, but keto-enol tautomerism is the most common. One structure in this form is a ketone, while the other is an enol. By using acid or basic catalysts, both tautomeric forms can be interconverted to one other. Enoliza is the process of converting a ketone to an enol.
Prototropy: The acid-base behaviour of a chemical is a form of tautomerism which happens. In this case, just the location of a proton differs from two versions. The same empirical formulation and the number of charges will apply to this structure.
Annular Tautomerism: If the heterocyclic system takes two or more positions, the phenomenon is referred to as ring tautomerism. Due to the removal of the proton, the tautomer named such tautomer is called ring chain tautomer, if a structure is converted to an open ring structure. Glucose is a model of tautomers in ring-chain.
Valence Tautomerism: Tautomerism in Valence is a sort of tautomerism where individual and double bonds of the molecule are continuously formed and ruptured without any group or atom movement. It is distinct and quick from the preceding form of tautomerism. There is a shift in geomechanical structure in this tautomerism, but no change in structure or mesomers for canonical resonance.
What Is the Distinction Between Resonance and Tautomerism?
Resonance and automerism are fundamental ideas in chemistry. The use of resonance to determine the true structure of a chemical molecule. The chemical structure of a molecule that is most stable under certain conditions is determined by tautomerism. There are several distinctions between the two words. The distinction between resonance and tautomerism is that resonance results from the interaction of lone electron pairs and bond electron pairs, whereas tautomerism results from the interconversion of organic compounds by relocating a proton.
Now, let’s understand what is isomers and isomerism?
The phenomenon of isomerism occurs when two or more compounds have the same chemical formula but distinct chemical structures. Isomers are chemical compounds with similar chemical formulas but differ in characteristics and atom arrangement in the molecule. As a result, substances that display isomerism are referred to as isomers.
Isomers don’t always have the same chemical or physical characteristics as one another. Structural or constitutional isomerism, in which the bonds between the atoms differ, and stereoisomerism or spatial isomerism, in which the bonds are the same but the relative locations of the atoms differ, are the two primary types of isomerism.
A hierarchy of isomeric connections exists. Two compounds may have the same constitutional isomer yet are stereoisomers of each other when examined further. Two molecules with the same stereoisomer but distinct conformational forms or isotopologues might be in various conformational forms or be separate isotopologues. The scope of the investigation is determined by the subject of research or the chemical and physical qualities that are of interest.
Here you must understand you need to know the basics of the chemistry to understand the advance theories. For example, you need to know the concept of molecular weight and molecular number before understanding the isomerism. I will suggest you to clear your basics from class 10th and 11th before understanding these topics. You can take help you various online platform such as doubtnut.com to strengthen you fundamentals. Revision is also an important part of chemistry. Revise the chapters of Chemistry as much as possible. It will keep everything fresh in your mind.
I hope the above information are helpful for you. All the best!