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Synthesis of phenanthridines via a novel photochemically-mediated cyclization and application to the synthesis of triphaeridine.

ABSTRACT: Readily synthesized biphenyl-2-carbaldehyde O-acetyl oximes were exposed to UV radiation affording phenanthridines. The scope and limitations of this novel reaction were explored. For example, exposure of 2',3'-dimethoxy-[1,1'-biphenyl]-2-carbaldehyde O-acetyl oxime to UV radiation afforded 4-methoxyphenanthridine in 54% yield. This methodology was applied to the synthesis of trisphaeridine to afford the product in four linear steps in an overall yield of 6.5% from 1-bromo-2,4,5-trimethoxybenzene.

SUBMITTER: Ntsimango S

PROVIDER: S-EPMC8450941 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature

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Synthesis of phenanthridines via a novel photochemically-mediated cyclization and application to the synthesis of triphaeridine.

Ntsimango Songeziwe S Ngwira Kennedy J KJ Bode Moira L ML de Koning Charles B CB

Beilstein journal of organic chemistry 20210908

Readily synthesized biphenyl-2-carbaldehyde O-acetyl oximes were exposed to UV radiation affording phenanthridines. The scope and limitations of this novel reaction were explored. For example, exposure of 2',3'-dimethoxy-[1,1'-biphenyl]-2-carbaldehyde O-acetyl oxime to UV radiation afforded 4-methoxyphenanthridine in 54% yield. This methodology was applied to the synthesis of trisphaeridine to afford the product in four linear steps in an overall yield of 6.5% from 1-bromo-2,4,5-tr ...[more]

PMID: 34621397

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