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N,N-Dimethylformamide-stabilized palladium nanoclusters as a catalyst for Larock indole synthesis.

ABSTRACT: We show that N,N-dimethylformamide-stabilized Pd nanoclusters (NCs) have high catalytic activity in the reaction of substituted 2-iodoanilines with alkynes to give 2,3-disubstituted indoles. This indole synthesis does not require phosphine ligands and proceeds with low Pd catalyst loadings. The Pd NCs were separated from the mixture after the reaction, and recycled at least three times. Transmission electron microscopy images showed that the Pd particle size before the reaction was 1.5-2.5 nm. The particle size after the reaction was 2-3 nm. X-ray photoelectron spectroscopy showed that the binding energy of the Pd NCs before the reaction was 335.0 eV.

SUBMITTER: Onishi K

PROVIDER: S-EPMC9079145 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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N,N-Dimethylformamide-stabilized palladium nanoclusters as a catalyst for Larock indole synthesis.

Onishi Kaito K Oikawa Kei K Yano Hiroki H Suzuki Takeyuki T Obora Yasushi Y

RSC advances 20180322 21

We show that N,N-dimethylformamide-stabilized Pd nanoclusters (NCs) have high catalytic activity in the reaction of substituted 2-iodoanilines with alkynes to give 2,3-disubstituted indoles. This indole synthesis does not require phosphine ligands and proceeds with low Pd catalyst loadings. The Pd NCs were separated from the mixture after the reaction, and recycled at least three times. Transmission electron microscopy images showed that the Pd particle size before the reaction was ...[more]

PMID: 35542799

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