| Abstract
| - Enamines (1a−r) prepared from cyclohexanones, cyclohexane-1,3-diones, or tetralones led toarylamines (2a−r) in one pot when treated with a stoichiometric amount of palladium salts [PdCl2(MeCN)2] in acetonitrile in the presence of triethylamine at room temperature or at elevatedtemperature, in some cases for 5 min to 2 h. The initial electrophilic attack of palladium chlorideon the β-carbon of the enamines led to a σ-palladium species (8) which triggered a series of reactions(→ 9 → 10 → 11 → 12) destined for aromatization to give 2a−r in good yields. The intervention ofsuch a σ-palladium species has been attested by a trapping experiment. On the basis of this reactionmechanism, we have developed another new process capable of transforming acyclic compoundshaving 6-en-2-one frameworks (16, 23, 25) to arylamines (2s−u) when their enamines were treatedunder the similar conditions as above, featuring again the formation of σ-palladium species suchas 8 as the initial key intermediate.
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