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Primary activation of para-quinone methides by chiral phosphoric acid for enantioselective construction of tetraarylmethanes.

ABSTRACT: Demonstrated here is an asymmetric nucleophilic addition via primary activation of para-quinone methides (p-QMs) based on a chiral phosphoric acid catalytic system. In sharp contrast to previous CPA-based bifunctional activation processes that all required the nucleophiles to have an effective hydrogen bond donor unit (e.g., OH, NH), here no such unit is required in the nucleophile. N-protected indole nucleophiles were successfully utilized for the synthesis of chiral tetraarylmethanes with high efficiency and enantioselectivity under mild conditions. Therefore, this protocol significantly expanded the scope of asymmetric transformations of p-QMs.

SUBMITTER: Han Z

PROVIDER: S-EPMC10763553 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature

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Primary activation of para-quinone methides by chiral phosphoric acid for enantioselective construction of tetraarylmethanes.

Han Zhengyu Z Zhu Biao B Zang Yu Y Zhang Chaoshen C Dong Xiu-Qin XQ Huang Hai H Sun Jianwei J

Chemical science 20231202 2

Demonstrated here is an asymmetric nucleophilic addition via primary activation of para-quinone methides (p-QMs) based on a chiral phosphoric acid catalytic system. In sharp contrast to previous CPA-based bifunctional activation processes that all required the nucleophiles to have an effective hydrogen bond donor unit (e.g., OH, NH), here no such unit is required in the nucleophile. N-protected indole nucleophiles were successfully utilized for the synthesis of ...[more]

PMID: 38179542

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