Palladium-Catalyzed Synthesis of Amidines via tert-Butyl isocyanide Insertion

Noémi Pálinkás, L. Kollár, T. Kégl

Research output: Contribution to journalArticle

Abstract

Para-substituted iodobenzenes were reacted with tert-butyl isocyanide and piperidine as nucleophiles in the presence of palladium-diphosphine catalysts. Both single and double insertion of the isocyanide was observed and the corresponding amidines and ketimine-amidines were obtained in yields of practical interest. With the increase of the tert-butyl isocyanide/iodobenzene ratio, 100% chemoselectivity toward the ketimine-amidine was achieved. The formation of the products was rationalized on the basis of a catalytic cycle analogous to that of the aminocarbonylation reactions. Clear connection was found between the activity and the electronic structure of the proposed catalyst Pd(diphosphine) by computational studies, as the more negative partial charge on palladium resulted in higher conversion. Among five isocyanide substrates, only tert-butyl isocyanide was proved to be active.

Original languageEnglish
Pages (from-to)16118-16126
Number of pages9
JournalACS Omega
Volume3
Issue number11
DOIs
Publication statusPublished - Nov 28 2018

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Amidines
Palladium
Cyanides
Iodobenzenes
Nucleophiles
Catalysts
Electronic structure
Substrates
tert-butyl isocyanide
ketimine

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)

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Palladium-Catalyzed Synthesis of Amidines via tert-Butyl isocyanide Insertion. / Pálinkás, Noémi; Kollár, L.; Kégl, T.

In: ACS Omega, Vol. 3, No. 11, 28.11.2018, p. 16118-16126.

Research output: Contribution to journalArticle

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