Premium
Addition reactions of heterocycles. VI . Reactions of 1,2‐dimethylpyrrole and 1‐methyl‐2‐carbomethoxypyrrole with nitrilimines
Author(s) -
Ruccia Michele,
Vivoicolò,
Cusmano Giuseppe
Publication year - 1978
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.5570150222
Subject(s) - chemistry , tautomer , pyrrole , adduct , ring (chemistry) , cleavage (geology) , medicinal chemistry , diradical , cycloaddition , pyrrolidine , organic chemistry , catalysis , physics , geotechnical engineering , fracture (geology) , nuclear physics , singlet state , engineering , excited state
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 C 2 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.