
%0 Journal Article
%A Freeman, DJ 
%A Newcombe, PJ 
%A Norris, RK 
%T An ionic chain mechanism for the substitution of an acetate group by the 2-Nitropropan-2-ide ion in benzylidene diacetates
%J Australian Journal of Chemistry
%D 1976/02/01
%V 29
%N 2
%P 327-337
%K 
%R https://doi.org/10.1071/CH9760327
%U https://www.publish.csiro.au/paper/CH9760327 
%X The reaction of 16 arylmethylene diacetates [benzylidene diacetates; ArCH(OAc)2] with lithium 2-nitropropan-2-ide in dimethyl sulphoxide has been studied. With the exception of aryl rings bearing strongly electron-donating substituents a ready reaction takes place giving l-aryl-2-methyl-2-nitropropyl acetates in good yield. The mechanism of this reaction, in which an acetate group is formally substituted by a (CH3)2C(N02) group, has been shown to be an ionic chain mechanisminvolving nucleophilic cleavage of the diacetate to catalytic quantities of the corresponding arene carbaldehyde (ArCHO) which subsequently undergoes a Henry condensation followed by a transacetylation reaction. In some cases (nitro heteroaromatic derivatives) a subsequent elimination reaction gives enol-acetates [ArC(OAc)=C(CH3)2]. 
