NOVELTY - Preparing sordidin comprises either (a) preparing 4-(2-ethyl-1,3-dioxolan-2-yl)pentan-2-one (IV) by oxidizing 2-ethyl-2-(pent-4-en-2-yl)-1,3-dioxolane (III) in presence of a catalyst, or step (a) as above per se, converting (IV) by magnesium coupling with allyl magnesium halide to form 6-(2-ethyl-(1,3)dioxolan-2-yl)-4-methyl-hept-1-en-4-ol (V), oxidizing (V) to form 4-(2-ethyl-(1,3)dioxolan-2-yl)-2-methyl-1-oxiranyl-pentan-2-ol (VI), epoxy ring opening of (VI) to form 6-(2-ethyl-(1,3)dioxolan-2-yl)-4-methyl-heptane-2,4-diol (VII), and cyclizing (VII) to form sordidin.    USE - The method is useful for preparing sordidin (claimed), which is useful in wells traps (associated with an insecticide or a pathogen) for placing on banana plantation soils to reduce and control weevil populations. No biological data given.    ADVANTAGE - The method: improves the overall efficiency of the synthesis of sordidin by utilizing single reaction step, and eliminates the use of hazardous, expensive and/or higly toxic reagents including osmium tetroxide, hence economical and environmentally friendly; and can be implemented at industrial scale easily.    DETAILED DESCRIPTION - Preparing sordidin, comprises either preparing (a) 4-(2-ethyl-1,3-dioxolan-2-yl)pentan-2-one of formula (IV) by oxidizing 2-ethyl-2-(pent-4-en-2-yl)-1,3-dioxolane of formula (III) in the presence of a catalyst comprising transition metal organometallic complexes, or the step (a) as above per se, followed by conversion of (IV) by magnesium coupling with allyl magnesium halide to form 6-(2-rthyl-(1,3)dioxolan-2-yl)-4-methyl-hept-1-en-4-ol (V), oxidizing (V) to form 4-(2-ethyl-(1,3)dioxolan-2-yl)-2-methyl-1-oxiranyl-pentan-2-ol (VI), epoxy ring opening of (VI) to form 6-(2-ethyl-(1,3)dioxolan-2-yl)-4-methyl-heptane-2,4-diol (VII), and cyclizing (VII) to form sordidin. An INDEPENDENT CLAIM is also included for preparing (IV), comprising oxidizing (III) in the presence of the catalyst consisting of transition metal organometallic complexes.