The Kharasch addition is an organic reaction and a metal-catalysed free radical addition of CXCl3 compounds (X = Cl, Br, H) to alkenes. [1] The reaction is used to append trichloromethyl or dichloromethyl groups to terminal alkenes. The method has attracted considerable interest, [2] but it is of limited value because of narrow substrate scope and demanding conditions. [3]
The reaction mechanism involves free radicals of the general formula CXCl2 (X = Cl, H). For the precursors carbon tetrachloride and chloroform, the requisite radicals can arise by abstraction of a halogen atom by a electropositive metal. The addition proceeds in an anti-Markovnikov fashion. Early work linked the addition to olefin polymerization. [4] This addition is a step in a protocol known as atom transfer radical polymerization. [5]
An example of Kharasch addition is the synthesis of 1,1,3-trichloro-n-nonane from 1-octene and chloroform using an iron-based catalyst: [6]
The reaction was discovered by Morris S. Kharasch in the 1940s. [7] [8] [9]
The Kharasch addition is an organic reaction and a metal-catalysed free radical addition of CXCl3 compounds (X = Cl, Br, H) to alkenes. [1] The reaction is used to append trichloromethyl or dichloromethyl groups to terminal alkenes. The method has attracted considerable interest, [2] but it is of limited value because of narrow substrate scope and demanding conditions. [3]
The reaction mechanism involves free radicals of the general formula CXCl2 (X = Cl, H). For the precursors carbon tetrachloride and chloroform, the requisite radicals can arise by abstraction of a halogen atom by a electropositive metal. The addition proceeds in an anti-Markovnikov fashion. Early work linked the addition to olefin polymerization. [4] This addition is a step in a protocol known as atom transfer radical polymerization. [5]
An example of Kharasch addition is the synthesis of 1,1,3-trichloro-n-nonane from 1-octene and chloroform using an iron-based catalyst: [6]
The reaction was discovered by Morris S. Kharasch in the 1940s. [7] [8] [9]