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Asymmetric Catalysis with a Mechanically Point-Chiral Rotaxane.

ABSTRACT: Mechanical point-chirality in a [2]rotaxane is utilized for asymmetric catalysis. Stable enantiomers of the rotaxane result from a bulky group in the middle of the thread preventing a benzylic amide macrocycle shuttling between different sides of a prochiral center, creating point chirality in the vicinity of a secondary amine group. The resulting mechanochirogenesis delivers enantioselective organocatalysis via both enamine (up to 71:29 er) and iminium (up to 68:32 er) activation modes.

SUBMITTER: Cakmak Y

PROVIDER: S-EPMC4805306 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Asymmetric Catalysis with a Mechanically Point-Chiral Rotaxane.

Cakmak Yusuf Y Erbas-Cakmak Sundus S Leigh David A DA

Journal of the American Chemical Society 20160204 6

Mechanical point-chirality in a [2]rotaxane is utilized for asymmetric catalysis. Stable enantiomers of the rotaxane result from a bulky group in the middle of the thread preventing a benzylic amide macrocycle shuttling between different sides of a prochiral center, creating point chirality in the vicinity of a secondary amine group. The resulting mechanochirogenesis delivers enantioselective organocatalysis via both enamine (up to 71:29 er) and iminium (up to 68:32 er) activation modes. ...[more]

PMID: 26835978

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