Model Studies Toward the Synthesis of Natural Indans Utilizing a Thallium(III)-Mediated Ring-Contraction Reaction

Abstract

6-Methoxy-1-tetralone was transformed in six steps into an indan derivative related to the sesquiterpenes mutisianthol and jungianol. Key steps involve a thallium(III)-promoted ring-contraction (to assemble the indan unit) and a Wittig olefination (to attach the side chain).

Key words

indan - jungianol - mutisianthol - ring contraction - thallium trinitrate

References

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4

The relative configuration of mutisianthol and of jungianol was assigned by Bohlmann and co-workers [2] [5] as cis. However, synthetic studies of Ho and his group [3] have shown that the correct configuration for mutisianthol is trans. Moreover, the same group proposed that jungianol might also have a trans relationship.