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Unusual biaryl torsional strain promotes reactivity in Cu-catalyzed Sommelet-Hauser rearrangement.

ABSTRACT: A Cu-catalyzed Sommelet-Hauser dearomatization of dihydrophenanthridine and diazo compounds is reported for the synthesis of spiro-indolines. A spiro-structure with adjacent quaternary and tertiary carbon centers was constructed in one step as a single isomer. Increasing steric hindrance by introducing ortho-substituents dramatically improved substrate reactivity in this transformation.

SUBMITTER: Pan C

PROVIDER: S-EPMC6050577 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Unusual biaryl torsional strain promotes reactivity in Cu-catalyzed Sommelet-Hauser rearrangement.

Pan Chongqing C Guo Wenjing W Gu Zhenhua Z

Chemical science 20180614 26

A Cu-catalyzed Sommelet-Hauser dearomatization of dihydrophenanthridine and diazo compounds is reported for the synthesis of spiro-indolines. A spiro-structure with adjacent quaternary and tertiary carbon centers was constructed in one step as a single isomer. Increasing steric hindrance by introducing <i>ortho</i>-substituents dramatically improved substrate reactivity in this transformation. ...[more]

PMID: 30079198

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