compound of formula i in a tertiary amine then the reaction mixture is contacted with one equivalent or more of water the resulting product is a salt of the tertiary amine and a 2 2 dihalo 3 3 dimethylbutyric acid the salt can be converted to the free acid by treatment with mineral acid or it can be used directly in step b the product of step a is condensed with thiocarbohydrazide in a solvent at 20 u00b0 160 u00b0 c and 1 5 atmospheres the solvent can be water or any polar solvent that does not itself react with thiocarbohydrazide an alkali metal iodide accelerates the reaction but is not necessary preferred conditions are an aqueous solvent system sodium iodide catalyst a temperature of 50 u00b0 100 u00b0 c and a pressure of 1 2 atmospheres a mixture of 100 parts 3 3 dimethyl butyric acid 345 parts bromine and 10 parts phosphorous trichloride was heated to 150 u00b0 for one hour in a bomb the resulting solid after in vacuo removal of excess bromine and hydrogen bromide consisted of 45 2 2 dibromo 3 3 dimethyl butyric acid m p 241 u00b0 243 u00b0 c and 55 2 bromo 3 3 dimethylbutyric acid m p 56 u00b0 58 u00b0 c the dibromo acid preferentially crystallizes from the mixture upon recrystallization in hexane a mixture of 2 2 dibromo 3 3 dimethylbutyric acid 55 parts and thiocarbohydrazide 22 parts in 500 parts of 1 1 methanol and water was heated to reflux for five hours upon cooling the reaction mixture to 0 u00b0 c a solid formed and was collected the solid 4 amino 6 t butyl 3 mercapto 1 2 4 triazin 5 one was obtained.