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Palladium-catalyzed multicomponent synthesis of 2-imidazolines from imines and acid chlorides.

ABSTRACT: We describe the palladium-catalyzed multicomponent synthesis of 2-imidazolines. This reaction proceeds via the coupling of imines, acid chlorides and carbon monoxide to form imidazolinium carboxylates, followed by a decarboxylation. Decarboxylation in CHCl(3) is found to result in a mixture of imidazolinium and imidazolium salts. However, the addition of benzoic acid suppresses aromatization, and generates the trans-disubstituted imidazolines in good yield. Combining this reaction with subsequent nitrogen deprotection provides an overall synthesis of imidazolines from multiple available building blocks.

SUBMITTER: Xu B

PROVIDER: S-EPMC6269033 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Palladium-catalyzed multicomponent synthesis of 2-imidazolines from imines and acid chlorides.

Xu Boran B Worrall Kraig K Arndtsen Bruce A BA

Molecules (Basel, Switzerland) 20121122 12

We describe the palladium-catalyzed multicomponent synthesis of 2-imidazolines. This reaction proceeds via the coupling of imines, acid chlorides and carbon monoxide to form imidazolinium carboxylates, followed by a decarboxylation. Decarboxylation in CHCl(3) is found to result in a mixture of imidazolinium and imidazolium salts. However, the addition of benzoic acid suppresses aromatization, and generates the trans-disubstituted imidazolines in good yield. Combining this reaction with subsequen ...[more]

PMID: 23174894

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