Preparation of 1-Bromobutane

Preparation of 1-Bromobutane

The mechanism is SN2.

CAUTION: Wear gloves during the entire experiment

Bring your 100 mL RBF, wide stem funnel, and cork ring to one of the balances.

Add 17 gm. NaBr to the flask, then proceed over to the tray with the water and

1-butanol repipettors.

Add 15 mL H2O and 10 mL 1-butanol to the flask and return to your hood workstation.

At your hood workstation, clamp the flask to the ringstand attached to your

hotplate/stirrer, add your magnetic stirring bar, and begin stirring the contents of the flask.

Bring a 50 or 100 mL beaker to the front of the lab and dispense 15 mL conc. H2SO4

Return to your hood workstation and S L O W L Y AND CAREFULLY the conc. H2SO4

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. ( see the figure on the next page )

Heat the flask gently (using the hot plate at a setting of about "4" ).

Continue gentle heating until the mixture begins to reflux. (liquid dripping from the condenser )

Once this is observed, continue "refluxing" the mixture for 60 minutes, controlling the

level of the vapor in the condenser so that it reaches no more than half-way up the

condenser

At the end of the 60 minute reflux period, discontinue heating

Add 700 mL of water to your 1L beaker

Once the contents of the flask ceases to bubble, remove the reflux condenser, unclamp the flask

from the ringstand and pour the contents of the flask into the Separatory funnel.

Immediately separate the lower aqueous layer from the organic layer and add it to the contents of your 1 L Beaker, WITH STIRRING. (Why is the aqueous layer on the bottom ? )

Extract the organic layer with