Abstract
Treatment of the neutral cyclopentanone adducts derived from the conjugate addition of each of lithiated 3-methylbut-2-enyl phenyl sulfoxide, (E)- and (Z)-but-2-enyldiphenylphosphine oxide to cyclopentenone with potassium t-butoxide results in intramolecular conjugate addition of the enolate arising from deprotonation at C 5 of the cyclopentanone with the vinyl sulfoxide or phosphine oxide in the side chain to generate bicyclo[2.2.1]heptanones in good yields. The use of an excess of lithium diisopropylamide at low temperature on the other hand results in kinetic deprotonation of the vinylic sulfoxide or phosphine oxide, and intramolecular nucleophilic addition of the resulting vinylic anions to the carbonyl groups in the respective adducts to generate bicyclo[3.2.1]octanols in acceptable yields. Application of the latter reaction to the lactone adduct of lithiated 3-methylbut-2-enyl phenyl sulfoxide and crotonolactone results in ring opening of the lactone to give a 2-(phenylsulfinyl)cyclohex-2-enone.
Original language | English |
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Pages (from-to) | 1473-1483 |
Number of pages | 11 |
Journal | Australian Journal of Chemistry |
Volume | 42 |
Issue number | 9 |
DOIs | |
Publication status | Published - 1989 |