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In intramolecular organic reactions, two reaction sites are contained within a single molecule. This configuration elevates the effective concentration of the reacting partners resulting in high reaction rates. Many intramolecular reactions are observed where the intermolecular version does not take place.
In chemistry, the effective molarity (denoted EM) [1] is defined as the ratio between the first-order rate constant of an intramolecular reaction and the second-order rate constant of the corresponding intermolecular reaction (kinetic effective molarity) [1] [2] or the ratio between the equilibrium constant of an intramolecular reaction and the equilibrium constant of the corresponding ...
The Ugi reaction has been applied in combination with an intramolecular Diels-Alder reaction [16] in an extended multistep reaction. A reaction in its own right is the Ugi–Smiles reaction with the carboxylic acid component replaced by a phenol. In this reaction the Mumm rearrangement in the final step is replaced by the Smiles rearrangement. [17]
Intramolecular vibrational energy redistribution (IVR) is a process in which energy is redistributed between different quantum states of a vibrationally excited molecule, which is required by successful theories explaining unimolecular reaction rates [1] [2] such as RRKM theory. Such theories assume a full statistical redistribution between all ...
Similar reactions will occur far faster if the reaction is intramolecular. The effective concentration of acetate in the intramolecular reaction can be estimated as k 2 /k 1 = 2 x 10 5 Molar. However, the situation might be more complex, since modern computational studies have established that traditional examples of proximity effects cannot be ...
The intramolecular reaction of halohydrins in particular, gives epoxides. In the case of asymmetrical ethers there are two possibilities for the choice of reactants, and one is usually preferable either on the basis of availability or reactivity. The Williamson reaction is also frequently used to prepare an ether indirectly from two alcohols.
The Heck reaction is the palladium-catalyzed coupling of an aryl or alkenyl halide with an alkene to form a substituted alkene. [2] Intramolecular variants of the reaction may be used to generate cyclic products containing endo or exo double bonds. Ring sizes produced by the intramolecular Heck reaction range from four to twenty-seven atoms.
In the reaction, thermal or photochemical decomposition of N-halogenated amine 1 in the presence of a strong acid (concentrated sulfuric acid or concentrated CF 3 CO 2 H) generates a nitrogen radical intermediate. The radical then abstracts an intramolecular hydrogen atom to give a cyclic amine 2 (pyrrolidine or, in some cases, piperidine).