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(2aR,5S,6aS,8aS,E)-Ethyl 5-hy-droxy-7,7,8a-trimethyl-8-oxo-2,2a,6,6a,7,8,8a,8b-octa-hydro-1H-penta-leno[1,6-bc]oxepine-4-carboxyl-ate.

ABSTRACT: The title compound, C17H24O5, featuring a 2-carbeth-oxy-3-oxepanone unit in its intra-molecularly O-H⋯O hydrogen-bonded enol form, was obtained via [(CF3CO2)2Rh]2-catal-ysed intra-molecular O-H bond insertion in the α-diazo-ω-hy-droxy-β-ketoester, ethyl 4-[(1S,3aS,6R,6aS)-6-hy-droxy-2,2,3a-trimethyl-3-oxo-octa-hydro-penta-len-1-yl]-2-diazo-3-oxobutano-ate. The seven-membered oxacyclic ring, thus constructed on a cis-fused diquinane platform, was found to adopt a distorted boat-sofa conformation.

SUBMITTER: Mehta G

PROVIDER: S-EPMC3588985 | biostudies-literature |

REPOSITORIES: biostudies-literature

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