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Enantioselective C-H Arylation and Vinylation of Cyclobutyl Carboxylic Amides.

ABSTRACT: Chiral mono-N-protected aminomethyl oxazoline (MPAO) ligands are found to promote enantioselective C-H arylation and vinylation of the cyclobutyl carboxylic acid derivatives via Pd(II)/Pd(IV) redox catalysis. This ligand scaffold overcame two important limitations of the previous MPAHA (mono-N-protected ?-amino-O-methylhydroxamic acid) ligands-enabled asymmetric C-H activation/C-C coupling reactions of cyclic carboxylic amides through Pd(II)/Pd(0) catalysis: substrates containing ?-hydrogen atoms are not compatible; vinylation has not been developed. Sequential C-H arylation and vinylation of cyclobutanes are also accomplished to construct three consecutive chiral centers on the crowded cyclobutane rings, rendering this reaction highly versatile for the preparation of chiral cyclobutanes.

SUBMITTER: Wu QF

PROVIDER: S-EPMC5844484 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Enantioselective C-H Arylation and Vinylation of Cyclobutyl Carboxylic Amides.

Wu Qing-Feng QF Wang Xiao-Bing XB Shen Peng-Xiang PX Yu Jin-Quan JQ

ACS catalysis 20180205 3

Chiral mono-N-protected aminomethyl oxazoline (MPAO) ligands are found to promote enantioselective C-H arylation and vinylation of the cyclobutyl carboxylic acid derivatives via Pd(II)/Pd(IV) redox catalysis. This ligand scaffold overcame two important limitations of the previous MPAHA (mono-N-protected α-amino-O-methylhydroxamic acid) ligands-enabled asymmetric C-H activation/C-C coupling reactions of cyclic carboxylic amides through Pd(II)/Pd(0) catalysis: substrate ...[more]

PMID: 29531850

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