Abstract Treatment of geranylacetone with NaNO 2 in AcOH affords 6, 10-dimethyl-9- nitroundeca-5 E, 10-dien-2-one as the major product. This product was used to synthesize 6, 10-dimethyl-9-methyleneundec-5 E-en-2-one, a component of the essential oil from the