- Copper(II) Ethanoate-assisted Phosphonation of Aryl Halides
-
A mixed valence trinuclear copper complex 2> is formed in the reaction between a 2-halogenoaryl azo compound and a trialkyl phosphite in the presence of copper(II) ethanoate which gives the corresponding 2-(dialkylphosphonato)aryl azo compound.
- Connor, Joseph A.,Jones, Anthony C.,Price, Raymomd
-
-
Read Online
- Cyanide Substitution in Aryl Halides by Copper(I) Complexes Derived from Formamide and from Formaldehyde Oxime
-
The copper complexes , and derived from formamide, and and derived from formaldehyde oxime (formaldoxime) react with 2'-acetamido-6-bromo-4'-diethylamino-2,4-dinitroazobenzene, ArBr, to form the corresponding aryl cyanide, ArCN, and the products ArH and Ar2 of reductive substitution and biaryl coupling.Copper(I) bromide complexes are also formed.Kinetic studies of these reactions in acetonitrile solution show that the cyanation reactions are equal concentration, second-order processes in each case.The effect of a radial scavenger on the reaction suggests the involvement of radicals in the formation of Ar2, but not in the formation of ArCN.A mechanism involving concerted nucleophilic substitution within the co-ordination sphere of copper(I) is proposed.
- Connor, Joseph A.,Gibson, Danuta,Price, Raymond
-
p. 619 - 622
(2007/10/02)
-
- Phosphonation of Aryl Halides by Copper(I) Complexes of Trialkyl Phosphites
-
The copper complexes 2> (1; R=Me or Et), (bpy)> (2; R=Me or Et) (bpy is 2,2'-bipyridine), and 2> react with certain 2-halogenoazobenzene compounds, ArX, at room temperature to form the corresponding dialkyl arylphosphonates, ArP(O)(OR)2, and the products, ArH and Ar2, of reductive substitution and biaryl coupling.The ester, MeCO2R, and a copper(I) halide complex (e.g. >) are also formed.Kinetic studies of the reactions of some of these copper complexes with 2'-acetamido-6-bromo-4'-diethylamino-2,4-dinitroazobenzene in alcohol solution show that the phosphonation reactions are equal concentration second-order processes in each case.The effects of a radical scavenger and of light on the reaction suggest the involvement of radicals in the formation of ArH and Ar2, but not in the formation of ArP(O)(OR)2.The effects of different substituents in ArX, of changes in solvent, and of various additives on these reactions are investigated.A mechanism involving concerted nucleophilic substitution within the coordination sphere of copper(I) is proposed.
- Connor, Joseph A.,Dubowski, Danuta,Jones, Anthony,Price, Raymond
-
p. 1143 - 1148
(2007/10/02)
-