Synthesis of (+/-)-vibralactone.

Quan Zhou, Barry B Snider

Index: Org. Lett. 10(7) , 1401-4, (2008)

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Abstract

Reductive alkylation of methyl 2-methoxybenzoate with prenyl bromide and hydrolysis afforded methyl 6-oxo-1-prenyl-2-cyclohexenecarboxylate. Reduction of the ketone, hydrolysis, iodolactonization, ozonolysis, and intramolecular aldol reaction provided a spiro lactone cyclopentenal. Retro-iodolactonization with activated Zn, formation of the beta-lactone, and reduction of the aldehyde completed an efficient first synthesis of (+/-)-vibralactone. No protecting groups were used except for the novel use of an iodolactone to protect both the prenyl double bond and carboxylic acid.