Enantioselective synthesis of all-carbon quaternary stereogenic centers by catalytic asymmetric conjugate additions of alkyl and aryl aluminum reagents to five-, six-, and seven-membered-ring β-substituted cyclic enones

Angewandte Chemie - International Edition

Volumn 47, Issue 38, 2008, Pages 7358-7362

  May, Tricia L ^a   Brown, M Kevin ^a   Hoveyda, Amir H ^a  

^a BOSTON COLLEGE   (United States)

Author keywords

Asymmetric synthesis; Homogeneous catalysis; N heterocyclic carbenes; Organoaluminum reagents; Quaternary carbon centers

Indexed keywords

ALUMINA; CHEMICAL REACTIONS; COMPLEXATION; COPPER; COPPER COMPOUNDS; SYNTHESIS (CHEMICAL);

ASYMMETRIC SYNTHESIS; HOMOGENEOUS CATALYSIS; N-HETEROCYCLIC CARBENES; ORGANOALUMINUM REAGENTS; QUATERNARY CARBON CENTERS;

ALKYLATION;

ALUMINUM; CARBON; CYCLOALKANE DERIVATIVE;

ARTICLE; CATALYSIS; CHEMISTRY; STEREOISOMERISM;

ALUMINUM; CARBON; CATALYSIS; CYCLOPARAFFINS; STEREOISOMERISM;

EID: 53249101813     PISSN: 14337851     EISSN: None     Source Type: Journal    
DOI: 10.1002/anie.200802910     Document Type: Article

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50. The somewhat moderate yields for the reactions in Table 5, which are in spite of conversions greater than 98%, are partly due to difficulties associated with removal of biphenyl formed in the course of the transformation. Modified procedures that address this complication are under development.
51. See the Supporting Information for additional details.
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