In the synthesis of a diester experiment (Chemiluminescence) using 4-nitrophenol (procedure shown below), explain the significance / role of the reagents used:
-- What does triethylamine do?
-- What does oxalyl chloride do? Why must it be added slowly?
-- Why is a calcium carbonate drying tube used?
-- Why is cold acetone used to wash the solid product?
9. Test whether the obtained material exhibits chemiluminescence as described below Synthesis of the diesters You will perform this synthesis three times (once for each phenol). It is recommended that you set up one reaction, carry out the synthesis and then once you are done set up the last two reactions at the same time. It is recommended vou use a phenol from List 1 or List 2 first. Chemiluminescence You will perform this portion three times, once for each diester you prepare. It may be necessary to use a darkened roonm (lights off) to observe the chemiluminescence 1. Make sure that all glassware is dry Measure 4mL of a 0.6M solution of your chosen phenol in acetone and place this solution in a a 25 mL round bottom flask. Place a magnetic stirring bar in the flask. Add 0.35 mL of triethylamine to the flask. 1. Obtain 2 small glass vials or beakers 2. To the first vial, add 5mL of 3% hydrogen peroxide in acetonitrile. To the second beaker add 5 mL of a 0.002 M solution of either rubrene or 9,10-diphenylanthracene2 (these solutions are prepared for you) and several crystals of a single diester (a small spatula tip full). If you add too much ester you may not get good results. Make sure the crystals dissolve before proceeding. If your drawer is on the north side of the room (the TA's right) use rubrene, if 2. 3. Cool the mixture in an ice bath and, while stirring vigorously in the fumehood, slowly add 1.2 mL of oxalyl chloride dropwise. Allow the solution to stir momentarily after 4. 5. Add one drop of triethylamine Place a calcium carbonate drying tube on the flask. Remove the ice bath and stir the solution for 20-30 minutes at room temperature The color of the solution should be white or pale yellow. If the color of the solution becomes deep yellow add one or more drops of oxalyl chloride until the color of the reaction mixture turns pale yellow. our drawer is on the south side of the room (the TA's left) use 9,10- diphenylanthracene Move to the darkened hood and mix the two solutions. Record your observations both in vour notebook and on the board If you have time, you may also try anthracene as the dye (this is 3. 6. 4. 7. After the stirring is completed, filter the reaction, wash the solid with cold acetone, and allow the solid to dry over the filter paper. It is very important the all the acetone be In Lab Discussion After all the groups have completed the experiment, your TA will lead a discussion analyzing the results. This is partially for the benefit of those groups that might not have seen reliable results oved from the solid before continuing Obtain and IR spectrum of the diester you made from List 1. You do not need to obtain an IR of the other compounds 8. In your lab report make sure you