|
IUPAC Nomenclature For Organic Chemical Transformations
The IUPAC Nomenclature for Organic Chemical Transformations is a methodology for naming a chemical reaction. Traditionally, most chemical reactions, especially in organic chemistry, are named after their inventors, the so-called name reactions, such as Knoevenagel condensation, Wittig reaction, Claisen–Schmidt condensation, Schotten–Baumann reaction, and Diels–Alder reaction. A lot of reactions derive their name from the reagent involved like bromination or acylation. On rare occasions, the reaction is named after the company responsible like in the Wacker process or the name only hints at the process involved like in the halogen dance rearrangement. The IUPAC Nomenclature for Transformations was developed in 1981 and presents a clear-cut methodology for naming an organic reaction. It incorporates the reactant and product in a chemical transformation together with one of three transformation types: * Addition reactions end with ''-addition''. For example: hydro-bromo-addi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methodology
In its most common sense, methodology is the study of research methods. However, the term can also refer to the methods themselves or to the philosophical discussion of associated background assumptions. A method is a structured procedure for bringing about a certain goal, like acquiring knowledge or verifying knowledge claims. This normally involves various steps, like choosing a Sample (statistics), sample, Data collection, collecting data from this sample, and interpreting the data. The study of methods concerns a detailed description and analysis of these processes. It includes evaluative aspects by comparing different methods. This way, it is assessed what advantages and disadvantages they have and for what research goals they may be used. These descriptions and evaluations depend on philosophical background assumptions. Examples are how to conceptualize the studied phenomena and what constitutes evidence for or against them. When understood in the widest sense, methodology al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halogen Dance Rearrangement
The halogen dance rearrangement, also known as halogen scrambling, halogen migration, or halogen isomerization, is the migration of halogen substituents to a different position on an aromatic or heteroaromatic ring, resulting in a net positional shift of the halogen from its original location in the starting material to a new position in the product, effectively “dancing” across the ring. This transformation belongs to the broader class of 1,2-rearrangement reactions. It offers a powerful strategy for achieving functionalization at positions in aromatic and heteroaromatic systems, which are often inaccessible or challenging through conventional synthetic methods. Moreover, the halogen dance rearrangement enables strategic electrophilic interception at the vacated halogen site, concurrently establishing a newly nucleophilic centre at the halogen’s migrated position, thereby offering dual opportunities for site-selective functionalization. The sole driving force for this reaction ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IUPAC
The International Union of Pure and Applied Chemistry (IUPAC ) is an international federation of National Adhering Organizations working for the advancement of the chemical sciences, especially by developing nomenclature and terminology. It is a member of the International Science Council (ISC). IUPAC is registered in Zürich, Switzerland, and the administrative office, known as the "IUPAC Secretariat", is in Research Triangle Park, North Carolina, United States. IUPAC's executive director heads this administrative office, currently Greta Heydenrych. IUPAC was established in 1919 as the successor of the International Congress of Applied Chemistry for the advancement of chemistry. Its members, the National Adhering Organizations, can be national List of chemistry societies, chemistry societies, national Academy of Sciences, academies of sciences, or other bodies representing chemists. There are fifty-four National Adhering Organizations and three Associate National Adhering Organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pure And Applied Chemistry
''Pure and Applied Chemistry'' is the official journal for the International Union of Pure and Applied Chemistry (IUPAC). It is published monthly by Walter de Gruyter Walter de Gruyter GmbH, known as De Gruyter (), is a German scholarly publishing house specializing in academic literature. History The roots of the company go back to 1749 when Frederick the Great granted the Königliche Realschule in Be ... and contains recommendations and reports, and lectures from symposia. References Chemistry journals Academic journals established in 1960 De Gruyter academic journals {{Chemistry-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
IUPAC Nomenclature Of Chemistry
IUPAC nomenclature is a set of recommendations for naming chemical compounds and for describing chemistry and biochemistry in general. The International Union of Pure and Applied Chemistry (IUPAC) is the international authority on chemical nomenclature and terminology. History of the Standardisation of Nomenclature In 1787, Louis-Bernard Guyton de Morveau published his nomenclature recommendations in collaboration with fellow French chemists Berthollet, de Fourcroy and Lavoisier. This work however covered only what are now called inorganic compounds. With the expansion of organic chemistry in the 19th century, and a greater understanding of the structure of organic compounds, the need for a more global standardised nomenclature became more prominent. Following a series of meetings, the first of which was established in 1860 by August Kekulé, the Geneva Nomenclature of 1892 was created. Another entity called the International Association of Chemical Societies (IACS) existed, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substitution Reaction
A substitution reaction (also known as single displacement reaction or single substitution reaction) is a chemical reaction during which one functional group in a chemical compound is replaced by another functional group. Substitution reactions are of prime importance in organic chemistry. Substitution reactions in organic chemistry are classified either as electrophilic or nucleophilic depending upon the reagent involved, whether a reactive intermediate involved in the reaction is a carbocation, a carbanion or a free radical, and whether the substrate is aliphatic or aromatic. Detailed understanding of a reaction type helps to predict the product outcome in a reaction. It also is helpful for optimizing a reaction with regard to variables such as temperature and choice of solvent. A good example of a substitution reaction is halogenation. When chlorine gas (Cl2) is irradiated, some of the molecules are split into two chlorine radicals (Cl•), whose free electrons are stron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elimination Reaction
An elimination reaction is a type of organic reaction in which two substituents are removed from a molecule in either a one- or two-step mechanism. The one-step mechanism is known as the E2 reaction, and the two-step mechanism is known as the E1 reaction. The numbers refer not to the number of steps in the mechanism, but rather to the kinetics of the reaction: E2 is bimolecular (second-order) while E1 is unimolecular (first-order). In cases where the molecule is able to stabilize an anion but possesses a poor leaving group, a third type of reaction, E1cB-elimination reaction, E1CB, exists. Finally, the pyrolysis of xanthate and acetate esters proceed through an "internal" elimination mechanism, the Ei mechanism, Ei mechanism. E2 mechanism The E2 mechanism, where E2 stands for bimolecular elimination, involves a one-step mechanism in which ''carbon-hydrogen'' and ''carbon-halogen'' bonds break to form a double bond (''C=C molecular geometry, Pi bond''). The specifics of the re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrobromination
A hydrohalogenation reaction is the electrophilic addition of hydrogen halides like hydrogen chloride or hydrogen bromide to alkenes to yield the corresponding haloalkanes. : If the two carbon atoms at the double bond are linked to a different number of hydrogen atoms, the halogen is found preferentially at the carbon with fewer hydrogen substituents, an observation known as Markovnikov's rule. This is due to the abstraction of a hydrogen atom by the alkene from the hydrogen halide (HX) to form the most stable carbocation (relative stability: 3°>2°>1°>methyl), as well as generating a halogen anion. A simple example of a hydrochlorination is that of indene with hydrogen chloride gas (no solvent): : Alkynes also undergo hydrohalogenation reactions. Depending on the exact substrate, alkyne hydrohalogenation can proceed though a concerted protonation/nucleophilic attack (AdE3) or stepwise by first protonating the alkyne to form a vinyl cation, followed by attack of HX/X− to give ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Addition Reaction
In organic chemistry, an addition reaction is an organic reaction in which two or more molecule A molecule is a group of two or more atoms that are held together by Force, attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemi ...s combine to form a larger molecule called the '' adduct''.. An addition reaction is limited to chemical compounds that have multiple bonds. Examples include a molecule with a carbon–carbon double bond (an alkene) or a triple bond (an alkyne). Another example is a compound that has rings (which are also considered points of unsaturation). A molecule that has carbon— heteroatom double bonds, such as a carbonyl group () or imine group (), can undergo an addition reaction because its double-bond. An addition reaction is the reverse of an elimination reaction, in which one molecule divides into two or more molecules. For insta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Transformation
A chemical substance is a unique form of matter with constant chemical composition and characteristic properties. Chemical substances may take the form of a single element or chemical compounds. If two or more chemical substances can be combined without reacting, they may form a chemical mixture. If a mixture is separated to isolate one chemical substance to a desired degree, the resulting substance is said to be chemically pure. Chemical substances can exist in several different physical states or phases (e.g. solids, liquids, gases, or plasma) without changing their chemical composition. Substances transition between these phases of matter in response to changes in temperature or pressure. Some chemical substances can be combined or converted into new substances by means of chemical reactions. Chemicals that do not possess this ability are said to be inert. Pure water is an example of a chemical substance, with a constant composition of two hydrogen atoms bonded to a s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wacker Process
The Wacker process or the Hoechst-Wacker process (named after the chemical companies of the same name) is an industrial chemical reaction: the aerobic oxidation of ethylene to acetaldehyde in the presence of catalysis, catalytic, aqueous palladium(II) chloride and copper(II) chloride. : The Tsuji-Wacker oxidation refers to a family of reactions inspired by the Wacker process. In Tsuji-Wacker reactions, palladium(II) catalyzes transformation of Α-olefin, α-olefins into carbonyl compounds in various Solvent, solvents. : The development of the Wacker process popularized modern organopalladium chemistry, and Tsuji-Wacker oxidations remain in use today. History The Wacker process was one of the first homogeneous catalysis with organopalladium chemistry applied on an industrial scale. In an 1893 doctoral dissertation on Marcellus natural gas trend, Pennsylvanian natural gas, Francis Clifford Phillips had reported that palladium(II) chloride oxidized ethylene to acetaldehyde, but the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Reaction
A chemical reaction is a process that leads to the chemistry, chemical transformation of one set of chemical substances to another. When chemical reactions occur, the atoms are rearranged and the reaction is accompanied by an Gibbs free energy, energy change as new products are generated. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and breaking of chemical bonds between atoms, with no change to the Atomic nucleus, nuclei (no change to the elements present), and can often be described by a chemical equation. Nuclear chemistry is a sub-discipline of chemistry that involves the chemical reactions of unstable and radioactive Chemical element, elements where both electronic and nuclear changes can occur. The substance (or substances) initially involved in a chemical reaction are called reagent, reactants or reagents. Chemical reactions are usually characterized by a chemical change, and they yield one or more Product (c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
