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Metal-free tandem carbene N-H insertions and C-C bond cleavages.

ABSTRACT: A metal-free C-H [5 + 1] annulation reaction of 2-arylanilines with diazo compounds has been achieved, giving rise to two types of prevalent phenanthridines via highly selective C-C cleavage. Compared to the simple N-H insertion manipulation of diazo, this method elegantly accomplishes a tandem N-H insertion/S_EAr/C-C cleavage/aromatization reaction, and the synthetic utility of this new transformation is exemplified by the succinct syntheses of trisphaeridine and bicolorine alkaloids.

SUBMITTER: Chen P

PROVIDER: S-EPMC8178978 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Metal-free tandem carbene N-H insertions and C-C bond cleavages.

Chen Pu P Nan Jiang J Hu Yan Y Kang Yifan Y Wang Bo B Ma Yangmin Y Szostak Michal M

Chemical science 20201110 2

A metal-free C-H [5 + 1] annulation reaction of 2-arylanilines with diazo compounds has been achieved, giving rise to two types of prevalent phenanthridines via highly selective C-C cleavage. Compared to the simple N-H insertion manipulation of diazo, this method elegantly accomplishes a tandem N-H insertion/SEAr/C-C cleavage/aromatization reaction, and the synthetic utility of this new transformation is exemplified by the succinct syntheses of trisphaeridine and bicolorine alk ...[more]

PMID: 34163814

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