Preparation of 1-Bromobutane

The mechanism is SN2. The overall reaction is:

H2SO4 + NaBr + CH3CH2CH2CH2OH 6 CH3CH2CH2CH2Br + H2O + NaHSO4

Boiling Point 118oC Boiling Point 92oC

Day 1

CAUTION: Wear gloves during the entire experiment
Fill out the table on your lab report form for this experiment INCLUDING YOUR NAME AND DATE and turn it in to the instructors box in NSM B-202 by 10:AM the day of the experiment. BE SURE TO DATE-STAMP YOUR LAB REPORT FORM USING THE DATE STAMP IN THE DEPARTMENT OFFICE (NSM-B-202) BEFORE PLACING IT INTO YOUR INSTRUCTORS BOX. FAILURE TO DO SO WILL RESULT IN YOUR FORM BEING MARKED "LATE". The report form will be returned to you in the lab.

At your hood workstation, place a hotplate/stirrer atop a ringstand .

Take a 250-mL round-bottomed flask, and clamp the flask to the ringstand, leaving about 1 inch of room between the bottom of the flask and a plastic bowl, whish sits atop the hotplate/stirrer..

Add 0.3 mole 1-butanol and ABOUT 35mL H2O to the flask and begin stirring the solution with the magnetic stirrer.

CAREFULLY add 0.3 mole NaBr to the reaction flask.

NOW, Add a slurry of ice and water to the bowl beneath the flask.

S L O W L Y AND CAREFULLY add 35mL conc. H2SO4 to the flask.

Remove the ice bath and replace it with a heating mantle.

Add two or three boiling chips to the flask. Equip the flask with a reflux condenser and begin circulating water through it, water going in the bottom and out the top of the condenser jacket (see Figure on next page).

Heat the flask gently (using a heating mantle setting of about 50% of capacity).

Continue gentle heating until the mixture begins to reflux.

Once this is observed, continue "refluxing" the mixture for 45 minutes, controlling the level of the