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Magee DI, Ratshonka S, McConaghy J, Hood M. Synthesis of β- and β,β-substituted Morita–Baylis–Hillman adducts using a two-step protocol. CAN J CHEM 2012. [DOI: 10.1139/v2012-017] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The synthesis of a large number of β- and β,β-substituted keto esters was successful by the use of the Knoevenagel condensation reaction. The stereoselectivity of these reactions was improved by alteration of various substituent groups. Although there were few examples of complete Z selectivity, the use of tert-butyl acetoacetate with either aromatic or aliphatic aldehydes afforded Z selectivity. The selective reductions of these substituted keto esters was successfully achieved by using a combination of NaBH4 and CeCl3·7H2O or Yb(OTf)3, which allowed a facile synthesis of a large number of stereochemically pure substituted Morita–Baylis–Hillman adducts, including β,β-substituted adducts.
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Affiliation(s)
- David I. Magee
- Department of Chemistry, P.O. Box 4400, University of New Brunswick, Fredericton, NB E3B 5A3, Canada
| | - Same Ratshonka
- Department of Chemistry, P.O. Box 4400, University of New Brunswick, Fredericton, NB E3B 5A3, Canada
| | - Jessica McConaghy
- Department of Chemistry, P.O. Box 4400, University of New Brunswick, Fredericton, NB E3B 5A3, Canada
| | - Maggie Hood
- Department of Chemistry, P.O. Box 4400, University of New Brunswick, Fredericton, NB E3B 5A3, Canada
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