Abstract
A short and efficient route to δ-lactone-fused cyclopentanoids starting from the easily accessible Diels-Alder adducts between homoallylic alcohol acetates and 1,2,3,4-tetrachloro-5,5-dimethoxycyclopenta-1,3-diene is reported. Since homoallyl alcohols were derived from the corresponding aldehydes RCHO (R = alkyl, aryl) through allyl metal addition, the methodology is broad in scope with regard to the choice of R group. The initially formed 1:1 diastereomeric mixture of adducts were subjected to ruthenium-catalyzed oxidation followed by acid-mediated hydrolysis of the acetate groups to obtain the hemiacetals 6a-e. Alkaline H2O2-mediated cleavage of the hemiacetals led, after esterification with diazomethane, to a chromatographically separable diastereomeric mixture of 7 and 8 in high overall yield (54-68%).
Original language | English (US) |
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Pages (from-to) | 1054-1060 |
Number of pages | 7 |
Journal | Synthesis |
Issue number | 7 |
DOIs | |
State | Published - Apr 3 2007 |
Externally published | Yes |
Keywords
- Diastereomers
- Diels-Alder reactions
- α-diketones
- α-keto hemiacetals
- δ-lactones