
%0 Journal Article
%A Newcombe, PJ 
%A Norris, RK 
%T Substitution reactions of nitrothiophens. V. Isolation and reactions of the exocyclic methylene intermediates in SN(AEAE) reactions
%J Australian Journal of Chemistry
%D 1982/05/01
%V 35
%N 5
%P 973-988
%K 
%R https://doi.org/10.1071/CH9820973
%U https://www.publish.csiro.au/paper/CH9820973 
%X The reaction of lithium 2-nitropropan-2-ide(1)with 2-(1'-chloro-2',2'-dimethylpropyl)-4-nitrothiophen (5) gives a complex mixture of products, including the salt (15), nitro compounds (17a-c)and oximes (18) and (19). The formation of these products can be rationalized in terms of initial formation of 5-[(Z)-2',2'-dimethylpropylidene]-2-(1''-methyl-1''-nitroethyl)-3-nitro-2,5-dihydrothiophen (16) whose analogues have been proposed as reactive intermediates in the SN(AEAE) reaction. The diene (16), which is a stable isolable compound [tautomeric with the thiophen (27)], reacts with the salt (1) to give the above products and with sodium p-toluenesulfinate to give the sulfone(32). The analogous chloride (6) and the acetate (7) react in a similar fashion and give the diene (21), which also reacts in part in an SN(AEAE) reaction to give the substitution product (23). 
