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<A NAME="RY10303ST-2">2</A> For a recent review, see:
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These reactivity trends are also seen in cyclizations of congeneric substrates having
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The trimethylsilyl congeners of propargyl alcohols 13b and 14b were found to be labile under the thio-Prins-pinacol reaction conditions, therefore
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Attempted silylation of these allylic alcohols with(trimethylsilyl)imidazole at 120
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<A NAME="RY10303ST-16">16</A>
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cis-Fused lactone 20 likely exists in two low energy chair conformations. Molecular mechanics calculations
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Cyclohexanones 27 were identified by 1H NMR, COSY NMR, and mass spectrometry.
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These two trace hydroazulenone products were identified by mass spectrometry and 1H NMR analysis. Neither of these products was hydroazulenone 26.
<A NAME="RY10303ST-25">25</A>
An isomer of 31 with uncertain structure was also isolated in 7% yield; it was not a stereoisomer
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<A NAME="RY10303ST-26">26</A>
Trace amounts of alkene-containing products were detected in 1H NMR spectra of the crude reaction mixtures.
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1
