Rearrangement reaction

A 1,2-rearrangement is an organic reaction where a substituent moves from one atom to another atom in a chemical compound. In a 1,2 shift the movement involves two adjacent atoms but moves over larger distances are possible. Skeletal isomerization is not normally encountered in the laboratory, but is the basis of large applications in oil refineries. In general, straight-chain alkanes are converted to branched isomers by heating in the presence of a catalyst. Examples include isomerisation of n-butane to isobutane and pentane to isopentane. Highly branched alkanes have favorable combustion characteristics for internal combustion engines. : Further examples are the Wagner–Meerwein rearrangement: : and the Beckmann rearrangement, which is relevant to the production of certain nylons: : ==Pericyclic reactions==

A pericyclic reaction is a type of reaction with multiple carbon–carbon bond making and breaking wherein the transition state of the molecule has a cyclic geometry, and the reaction progresses in a concerted fashion. Examples are hydride shifts and the Claisen rearrangement: ==Other rearrangement reactions==

1,3-rearrangements 1,3-rearrangements take place over 3 carbon atoms. Examples: • the Fries rearrangement • a 1,3-alkyl shift of verbenone to chrysanthenone ==See also==