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Enantioselective Benzylation and Allylation of ?-Trifluoromethoxy Indanones under Phase-Transfer Catalysis.

ABSTRACT: The organo-catalyzed enantioselective benzylation reaction of ?-trifluoromethoxy indanones afforded ?-benzyl-?-trifluoromethoxy indanones with a tetrasubstituted stereogenic carbon center in excellent yield with moderate enantioselectivity (up to 57% ee). Cinchona alkaloid-based chiral phase transfer catalysts were found to be effective for this transformation, and both enantiomers of ?-benzyl-?-trifluoromethoxy indanones were accessed, depended on the use of cinchonidine and cinchonine-derived catalyst. The method was extended to the enantioselective allylation reaction of ?-trifluoromethoxy indanones to give the allylation products in moderate yield with good enantioselectivity (up to 76% ee).

SUBMITTER: Liang Y

PROVIDER: S-EPMC6696116 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Enantioselective Benzylation and Allylation of α-Trifluoromethoxy Indanones under Phase-Transfer Catalysis.

Liang Yumeng Y Maeno Mayaka M Zhao Zhengyu Z Shibata Norio N

Molecules (Basel, Switzerland) 20190730 15

The organo-catalyzed enantioselective benzylation reaction of α-trifluoromethoxy indanones afforded α-benzyl-α-trifluoromethoxy indanones with a tetrasubstituted stereogenic carbon center in excellent yield with moderate enantioselectivity (up to 57% ee). Cinchona alkaloid-based chiral phase transfer catalysts were found to be effective for this transformation, and both enantiomers of α-benzyl-α-trifluoromethoxy indanones were accessed, depended on the use of cinchonidine and cinchonine-derived ...[more]

PMID: 31366139

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