This document describes the synthesis of tert-butyl chloride from tert-butanol and concentrated hydrochloric acid, including the separation and purification steps.
Extract
[...] mL of tertiobutanol and . mL of HCl. Attention to well degas when adding the acid to the decanting ampoule regularly by pointing the tap of the ampoule inside the fume hood to avoid acid splashes on oneself. The assembly presented itself according to the following scheme with the reagents: One can notice that the solution in the decanting ampoule becomes slightly cloudy. Once 20 minutes have passed, we leave the decanting ampoule on its support with the stopper open in order to allow the solution to decant and obtain two well-differentiated phases. [...]
[...] We add magnesium sulfate to the erlenmeyer until a little powder is in suspension, this indicates that there is no more water to absorb to agglomerate. From this moment on, we place a little cotton in a liquid funnel to retain the magnesium sulfate and recover the filtrate. We now perform a distillation setup according to the following scheme: We measure the mass beforehand of the recovery balloon, then install it on the bent arm using clip joints. The mass before distillation of the recovery balloon is: . g. [...]
[...] This phase change comes to thermally stabilize the medium during the complete passage of tert-butyl chloride to the vapor phase. At the moment when the temperature rises, we know that we can remove the recovery balloon because there is no longer any tert-butyl chloride left in the reaction medium. Now weigh the balloon with the distillate, it has a mass of: . g. We will calculate the yield in the results section. The boiling point of our compound is the temperature at which our distillation apparatus stabilized when we recovered the desired distillate fraction. [...]
[...] : p = (density / density of water) = density ; m = mass ; M = molar mass (g/mol) ; n = number of moles Tertiobutanol : Concentrated hydrochloric acid : We note that the limiting reactant is the . Knowing that the reaction takes place in 1:1 on the stoichiometric coefficients. We can then deduce that: Thus we can calculate the experimental number of moles of our reaction from the weighed mass of the recovery balloon: [...]
[...] We deduce that the boiling point of our compound is: . °C. We can now measure the refractive index, for this we use an Abbe refractometer. We place a drop of the liquid to be measured on the glass plate (black arrow). We then close the stopcock and direct the lamp towards the refractometer. We obtain a refractive figure on the lens that appears as a horizontal line that we must place in the center of the cross. The reading of the refractive index is made on the scale located at the bottom. [...]
