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Palladium(0)/benzoic acid catalysis merges sequences with D2O-promoted labelling of C-H bonds.

ABSTRACT: The combination of a Pd(0) complex with benzoic acid in the presence of D2O enables the synthesis of valuable families of highly deuterated organics through elaborate sequential reactions. The catalytic system can convert 2-butyne fragments into the corresponding d-dienamides, which can then readily deliver labeled polycyclic quinone motifs. Propargylated tryptamines lead to formation of highly enriched tetrahydrocarbolines through the C-H activation of their unprotected indole ring. Mechanistic studies reveal the ordered series of events that regulate the outcome of these complex reactions, which include multiple, sequential and selective H/D scrambling from the cheapest and safest deuterium source.

SUBMITTER: Cera G

PROVIDER: S-EPMC6979390 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Palladium(0)/benzoic acid catalysis merges sequences with D2O-promoted labelling of C-H bonds.

Cera Gianpiero G Della Ca' Nicola N Maestri Giovanni G

Chemical science 20190925 44

The combination of a Pd(0) complex with benzoic acid in the presence of D2O enables the synthesis of valuable families of highly deuterated organics through elaborate sequential reactions. The catalytic system can convert 2-butyne fragments into the corresponding d-dienamides, which can then readily deliver labeled polycyclic quinone motifs. Propargylated tryptamines lead to formation of highly enriched tetrahydrocarbolines through the C-H activation of their unprotected indole ring. ...[more]

PMID: 32110316

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