DIASTEREOCONTROL OF THE CLAISEN REARRANGEMENT BY SUBSTITUENTS EXTERNAL TO THE PERICYCLIC ARRAY: SYNTHETIC STUDIES ON BETAENONE B AND STEMPHYLOXIN I

Article abstract of DOI:10.1016/S0040-4039(00)96286-5

Thermal Claisen rearrangement of substrates 5 and 6 each prepared in seven steps from the Diels-Alder adduct of methoxybenzoquinone and 1,3 butadiene, affords products 7 and 8 respectively.These disparate results demonstrate that the stereochemical outcome of Claisen rearrangements of this type may be controlled by the spatial requirements of substituents external to the pericyclic array.