Crude TBHP (0.53 kg, 4 mol) and 0.46 kg (4 mol) of DVC were sequentially loaded into a glass reactor equipped with an overhead mechanical stirrer and water bath. The mixture was stirred and cooled to 0 С by using ice water, followed by dropwise addition of 0.75 kg of 68% sulphuric acid to the reaction mixture over a period of 90 minutes, while keeping the temperature in the range of 0 to 5С. Subsequently, the mixture was stirred for an additional 90 minutes with a gradual raise of the temperature from 5С up to 10С and for another hour in which the mixture was allowed to warm to 10-12C. The reaction mixture was left to settle for 10 minutes, subsequently the upper organic layer was separated from the sulphuric acid layer, washed with water (160 mL) for 5 minutes under vigorous stirring and again separated from the bottom water layer after 10 minutes' settling. For the first alkaline washing, 100 mL of water and 40 mL of the 33 wt. % aqueous NaOH was added to the organic layer and the mixture was stirred for 5 minutes, after which the phase were allowed to separate for 10 minutes. The bottom aqueous alkaline layer was removed. This was repeated with 80 ml of the 33 wt. % aqueous NaOH. Subsequently, the organic layer was washed twice with 160 mL of the 33 wt. % NaOH. Dry magnesium sulphate (76 g) and 0.6 g of hydroquinone were charged to the organic layer, this mixture was stirred for 30 minutes, afterwards the product obtained was filtered off from the solid residue sealed and stored in a refrigerator until further use. As a result, 0.66 kg (90% yield) of the final crude product 5-tert-butylperoxy-5-methyl-1-hexen-3-yne also cold peroxide monomer (PM) with a purity of 98% (determined by gas chromatography) was obtained.