Preparation (1), condensation reaction of chloroterpentane and formaldehyde under acidic conditions, catalyzed by Zn/Co/Sb composite catalyst, reaction temperature of 60°C, reaction time of 5h, preparation of binastone, the ratio between the sum of substances of each component in the Zn/Co/Sb composite catalyst and the amount of substances of chloroterpentane is 3:50; (2) Using pinacone, sodium hydride and dimethyl carbonate as raw materials, toluene as solvent, stirring Chemicalbook reaction and cooling, 4, 4-dimethyl-3-oxy-valerate crude product at pH=4, pinacone water content < 0.2fft.%, toluene water content <0.2Wt.%; (3), 4, 4-dimethyl-dimethyl-3-oxy-valerate crude products were distilled under vacuum degree less than 1mmHg and temperature 90°C. The purity of 4, 4-dimethyl-3-oxy-valerate methyl ester was high, the yield was high, the main content was more than 98%, and the total yield was 96%.