Methyl 5,5-dimethyl-4-oxohexanoate (CAS no ), which is also known as , 5,5-dimethyl-4-oxo-, , could be produced through the following synthetic routes.

An oven-dried, 3-L, three-necked, round-bottomed flask equipped with a magnetic stirring bar is charged with 1000 mL of freshly distilled methylene chloride. One of the outer two necks of the flask is equipped with a gas inlet adapter attached to a nitrogen source and the other with a septum connected through a needle to a bubbler. A 125-mL pressure-equalizing addition funnel capped with a septum is placed in the center neck of the flask with the stopcock closed. The funnel is charged with 12.1 mL (150 mmol) of methylene iodide dissolved in 75 mL of distilled methylene chloride . The solution is stirred under nitrogen for 1 hr and the flask is cooled in an ice-water bath. Using a syringe, 15.4 mL (150 mmol) of neat diethylzinc is added to the methylene chloride through the septum. The stopcock of the addition funnel is opened carefully and the methylene iodide solution is allowed to drip into the diethylzinc solution over the course of 30 min. After the reaction is stirred for an additional 10 min, 8.0 mL (50 mmol) of methyl 4,4-dimethyl-3-oxopentanoate is added to the flask over a period of 15 sec through the septum using a syringe. The reaction mixture is stirred for 45 min, the septum is removed, and the reaction is quenched through the careful addition of 125 mL of saturated aqueous ammonium chloride. Stirring is maintained for an additional 10 min, at which time the reaction mixture is transferred to a 2-L separatory funnel. The lower organic layer is withdrawn and placed in a large, round-bottomed flask. The methylene chloride is removed using a rotary evaporator and the residue is diluted with 500 mL of diethyl ether and placed in the separatory funnel. It is washed successively with 125-mL portions of saturated aqueous sodium bicarbonate , 1 M aqueous sodium thiosulfate solution, deionized water and brine. The aqueous washings are extracted with diethyl ether (3 × 150 mL) and the combined organic layers are dried over 50 g of anhydrous sodium sulfate prior to concentration under reduced pressure. The product is purified by vacuum distillation from anhydrous potassium carbonate (58°C, 1 mm) to give methyl 5,5-dimethyl-4-oxo-hexanoate (7.63-8.09 g, 89-94% yield) as a clear liquid.