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Synthesis of complex hexacyclic compounds via a tandem Rh(II)-catalyzed double-cyclopropanation/Cope rearrangement/Diels-Alder reaction.

ABSTRACT: Treatment of (E)-1-(methoxymethylene)-1,2,3,4-tetrahydronaphthalene with styryl diazoacetates in the presence of catalytic amounts of the dirhodium complex Rh2(S-DOSP)4 provides a highly enantioenriched hexacyclic product with 10 new stereogenic centers. The transformation proceeds by a cascade sequence starting with a double cyclopropanation of a benzene ring, followed by a Cope rearrangement of a divinylcyclopropane and then an intramolecular Diels-Alder cycloaddition.

SUBMITTER: Spangler JE

PROVIDER: S-EPMC4168775 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature

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Synthesis of complex hexacyclic compounds via a tandem Rh(II)-catalyzed double-cyclopropanation/Cope rearrangement/Diels-Alder reaction.

Spangler Jillian E JE Lian Yajing Y Raikar Sandeep N SN Davies Huw M L HM

Organic letters 20140910 18

Treatment of (E)-1-(methoxymethylene)-1,2,3,4-tetrahydronaphthalene with styryl diazoacetates in the presence of catalytic amounts of the dirhodium complex Rh2(S-DOSP)4 provides a highly enantioenriched hexacyclic product with 10 new stereogenic centers. The transformation proceeds by a cascade sequence starting with a double cyclopropanation of a benzene ring, followed by a Cope rearrangement of a divinylcyclopropane and then an intramolecular Diels-Alder cycloaddition. ...[more]

PMID: 25208337

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