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Synthesis of a Conformationally Stable Atropisomeric Pair of Biphenyl Scaffold Containing Additional Stereogenic Centers.

ABSTRACT: The synthesis of a new CF₃-containing stereogenic atropisomeric pair of ortho-disubstituted biphenyl scaffold is presented. The atropisomers are surprisingly conformationally stable for isolation. X-ray structures show that their stability comes from an intramolecular hydrogen bond formation from their two hydroxyl groups and renders the spatial arrangement of their peripheral CF₃ and CH₃ groups very different. The synthesized stereogenic scaffold proved to be effective in catalyzing the asymmetric N-nitroso aldol reaction of enamine and nitrosobenzene. Compared to similar scaffolds without CF₃ groups, one of our atropisomer exhibits an increase in enantioselectivity in this reaction.

SUBMITTER: Yeung CT

PROVIDER: S-EPMC6385101 | biostudies-other | 2019 Feb

REPOSITORIES: biostudies-other

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Synthesis of a Conformationally Stable Atropisomeric Pair of Biphenyl Scaffold Containing Additional Stereogenic Centers.

Yeung Chi-Tung CT Chan Wesley Ting Kwok WTK Lo Wai-Sum WS Law Ga-Lai GL Wong Wing-Tak WT

Molecules (Basel, Switzerland) 20190212 3

The synthesis of a new CF₃-containing stereogenic atropisomeric pair of ortho-disubstituted biphenyl scaffold is presented. The atropisomers are surprisingly conformationally stable for isolation. X-ray structures show that their stability comes from an intramolecular hydrogen bond formation from their two hydroxyl groups and renders the spatial arrangement of their peripheral CF₃ and CH₃ groups very different. The synthesized stereogenic scaffold proved to be effective in catalyzing the asymmet ...[more]

PMID: 30759758

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