Addition reactions of heterocycles. VI. Reactions of 1,2-dimethylpyrrole and 1-methyl-2-carbomethoxypyrrole with nitrilimines |
| |
Authors: | Michele Ruccia Nicol Vivona Giuseppe Cusmano |
| |
Institution: | Michele Ruccia,Nicolò Vivona,Giuseppe Cusmano |
| |
Abstract: | Addition reactions of 1,2-dimethylpyrrole and 1-methyl-2-carbomethoxypyrrole with C-acetyl-N-phenylnitrilimine, have been investigated. 1,2-Dimethylpyrrole gives three different types of adducts: i.e. bis-cycloadducts (Vc) and (VIc), spirocycloadduct (IX), and non cyclic bis-adduct (XII). On the other hand, 1-methyl-2-carbomethoxypyrrole gives the bis-cycloadduct (VIb) only. Compound XII arises probably through a double 1,3-addition reaction, whereas the formation of cycloadducts Vc, VIc, and IX depends on the substituents present at C2 of the pyrrole ring and consequentially on the intermediary occurence of mono-cycloadduct (IIIc), its methylenic tautomer VII, VIc, and XL The behaviour of the cycloadducts towards heating or acidic treatment showed a termal cleavage of the pyrazoline ring and acidic cleavage of the pyrrolidine ring. |
| |
Keywords: | |
|
|