A stereoselective construction of a bicyclo[m.n.1] ring system from enol-lactones

Abstract

A stereoselective one-pot transformation of simple enol-lactone derivatives into the corresponding more complex compounds having the bicyclo[m.n.1] ring system was investigated. Under improved reduction conditions using DIBAL-H, the enol-lactones efficiently provided the bicyclo[m.n.1] derivatives via tandem reduction of the lactone moiety, aldol reaction and subsequent reduction of the resulting carbonyl functionality.

References

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13. X-Ray crystallographic analysis of 16 disclosed that compound 12 should have the structure described as (1R*, 2R*, 6S*, 10S*)-2,10-dihydroxy-8,9-benzobicyclo[4.3.1]dec-8-ene. Details of the X-ray analysis together with full experimental details will be reported elsewhere.
14. The starting enol-lactones were prepared according to the literature precedents (see ref. 5).
15. The corresponding 9-oxo derivatives could never be detected in more than trace quantities.