| 摘要 |
A novel process is disclosed for the preparation of pentaalkylchromenes of the general formula: (I) wherein each R denotes a lower alkyl group having from 1 to 4 C atoms and R1 denotes a phenyl group which is unsubstituted or substituted by a lower alkyl group having from 1 to 4 C atoms, by halogen or by a nitro group, or an alkanoyl group having from 1 to 4 C atoms. In the process, a trialkylhydroquinone is reacted with a halogenated butenol to give a substituted tetraalkylhydroquinone, which is oxidised and then the halogen atom is substituted with a suitable nucleophile. The resulting compound is finally cyclised to give the final product of formula I. The pentaalkylchromenes I are suitable intermediates for the preparation of hypolipidaemic pharmaceuticals.
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