- Unique Synthetic Utility of BF3*OEt2 in the Highly Diastereoselective Reduction of Hydroxy Carbonyl and Dicarbonyl Substrates
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. A new aspect of commonly used BF3*OEt2 has been illuminated by successfully demonstrating the unique but highly stereoselective reactions of hydroxy carbonyl and dicarbonyl substrates. For example, treatment of γ-hydroxy ketone 1c with BF2*OEt2/Bu3SnH in CH2Cl2 at -78 to -40 deg C afforded the corresponding 1,4-diol 2c with virtually complete diastereoselection, while use of TiCl4 as a Lewis acid under similar reaction conditions caused a total lack of diol yield and selectivity (17%; 2c/3c = 1.2:1), accompanied by a significant formation of 2,3-disubstituted tetrahydrofuran 4 (44%).
- Ooi, Takashi,Uraguchi, Daisuke,Morikawa, Junko,Maruoka, Keiji
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p. 2015 - 2018
(2007/10/03)
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- Synthesis of Deoxyfrenolicin and Nanaomycin A
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Deoxyfrenolicin and nanaomycin A have been synthesized.Key steps in the synthesis include a phtalide annulation reaction to produce a naphthoquinone, a tandem Diels-Alder/retro-Claisen reaction to produce the carbon skeleton, and a stereoselective reduction of a hemiketal.
- Kraus, George A.,Molina, Maria Teresa,Walling, John A.
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p. 1273 - 1276
(2007/10/02)
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