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Metal-Catalyzed Cyclotrimerization Reactions of Cyanamides: Synthesis of 2-Aryl-?-carbolines.

ABSTRACT: The synthesis of annulated 2-aryl-?-carboline heterocycles is described using transition metal catalysis. A linear strategy is described that uses Rh(I) catalysis to form the ?-carboline scaffold by [2+2+2] cyclotrimerization. Alternatively, a tandem catalytic approach using a Pd(II) precatalyst afforded the same target molecules by mediating a Sonogashira reaction and a [2+2+2] cyclotrimerization in the same reaction flask. In each case, nine different 2-aryl-?-carbolines have been prepared in high to modest isolated yields.

SUBMITTER: Medas KM

PROVIDER: S-EPMC7895322 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Metal-Catalyzed Cyclotrimerization Reactions of Cyanamides: Synthesis of 2-Aryl-α-carbolines.

Medas Kyle M KM Lesch Robert W RW Edioma Friendship B FB Wrenn Sean P SP Ndahayo Vincent V Mulcahy Seann P SP

Organic letters 20200407 8

The synthesis of annulated 2-aryl-α-carboline heterocycles is described using transition metal catalysis. A linear strategy is described that uses Rh(I) catalysis to form the α-carboline scaffold by [2+2+2] cyclotrimerization. Alternatively, a tandem catalytic approach using a Pd(II) precatalyst afforded the same target molecules by mediating a Sonogashira reaction and a [2+2+2] cyclotrimerization in the same reaction flask. In each case, nine different 2-aryl-α-carbolines have been prepared in ...[more]

PMID: 32255636

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