Note:  Commentaries are in color and placed in brackets.

Experiment 1: April 3, 2009 John Doe [date and signature] Purpose: Cyclohexene will be prepared from cyclohexanol. The product will be isolated by simple distillation. In addition, as a qualitative test for unsaturation, the reactivity of cyclohexene with KMnO4 and Br2 will observed. Reaction Schemes:

Physical Properties: [obtain physical properties from Aldrich Catalog in
the reference section of the library]



Cyclohexanol  100.2 1.3 mL 12 20-22 160-161 0.948 no/yes
Cyclohexene  82.2




85% H3PO4

0.4 mL




Conc. H2SO4

6 drops 




Bromine 159.8 2-5 drops
Dichloromethane 84.9 2-5 drops
Potassium permanganate 158.04 2-5 drops (in H2O) yes/no
1,2-Dimethoxyethane 2-5 drops

[note: both H3PO4 and H2SO4 are catalysis and thus mmol used, mw, mp, and bp are not significant]

Safety Considerations: Both H3PO4 and H2SO4 are corrosive and should avoid contact with skin.
Bromine is highly corrosive and CCl4 is a suspect carcinogen; use only in fume hood and avoid
contact. 5% aqueous sodium thiosulfate should be used for treatment of bromine burns. [obtained
from text and lecture; see special instructions section for exp.]

Waste Disposal Considerations: Organic residues are to be discarded in the designated
nonhalogenated waste bottle. However, solutions remaining after the bromine test should be placed
in the halogenated waste bottle. The KMnO4 waste should be discarded in a bottle labeled heavy
metal waste. [obtained from text; see waste disposal section of exp.]

Procedure Outline:

Apparatus Assembly

1. Place 1.3 mL of cyclohexanol w/plastic syringe & needle into a 5 mL conical vial

2. Add spin vane, 0.40 mL 85% H3PO4, 6 drops of conc. H2SO4 and mix thoroughly

3. Assemble distillation apparatus w/ air condenser (see figure 1). Do not charge with CaCl2 or any drying agent as suggested by text.

figure 1


1. Place aluminum collar around the vial and heat mixture until it starts to distill. Regulate heat so that distillation takes 30-45 mins.

2. Remove distillate w/ Pasteur pipette (when necessary) into a dry 3 mL conical vial. Stop when there is no more liquid to distill (i.e., when liquid STOPS boiling).

3. After distillation, remove as much distillate as possible. Rinse sides of Hickman w/ ~1 mL of saturated aq. NaCl.


Isolation and Drying of Product

1. Allow layers to separate and remove bottom aq. layer

2. Transfer organic layer w/ Pasteur pipette into a small test tube w/ 2 microspatulafuls of granular anhydrous Na2SO4.

3. Stopper test tube and allow 5-10 mins for water removal.

4. This is a good time to wash and dry Hickman and 3 mL conical vial.


1. Transfer the dry liquid to a clean, dry 3 mL conical vial (leaving solid behind).

2. Add a boiling stone (and NOT spin vane) and assemble distillation apparatus (Figure 1).

3. Heat to 140-150 °C (or whatever temp. it takes to distill)

4. Collect and transfer distillate to a small tared vial with cap.

5. Weigh and calc. % yield.

IR Spectrum

Obtain IR spectrum of product. TA will DEMO operation for ATR setup.

Unsaturation Test

1. Do in Hood. Place one drop of product into a test tube. Add ~0.50 mL CH2Cl2/Br2 soln. and note any color changes. Text suggest to continue adding CCl4/Br2 soln. until color no longer discharge However, DO NOT do this.

2. Do the above procedure on the starting material, cyclohexanol.

3. Place 4-5 drops of product into another test tube. Add 0.3 mL of 1,2-dimethoxyethane and then add KMnO4 drop by drop until color is gone (will have ppt.).

4. Do the above procedure on the starting material, cyclohexanol.

Observations and variations:


cyclohexanol solidified in dispensing bottle; had to warm bottle in hot water bath













Increased hotplate temp. to 180°C

Distillation took 40 mins.




Used 1.5 mL of aq. NaCl soln.





Organic layer was cloudy


Dried 5 mins




Trace amount of solid transferred over



increased temp. to 180°C


tared vial = 20.982 g

sample + vial = 21.340 g


obtained IR of sample on silver chloride plates



[place your observations for unsaturation tests here]

Results: [show all calculations]

Cyclohexanol is limiting reagent thus,
Cyclohexene isolated
mass cyclohexene = 21.340g-20.982g = 0.358 g

Experimental Yield
IR Data Table (neat): [in this example the IR spectrum is not included; however, you
need to include an IR spectrum of your compound]

 Wavenumber (cm-1) Assignment Comments
3024, 3061 2934 1662 718=C­H unsaturated stretching C­H saturated stretching C=C stretch, alkene =C­H out-of-plane bending

Concluding Comments: [Generally, the conclusion should be brief and concise. The conclusion should focus on sources of error, possible improvements either in technique or procedure. Comments on your % yield and the purity of your product. How did my %yield compare to the literature (see your lecture text)? Why was a certain procedure used? E.g., Why was a saturated solution of NaCl used? Were there any unexpected results? Please do not take these above suggestions as your sole guideline for your conclusion. The concluding comments should be your own and should cover those issues that you feel are important to the experiment at hand. Finally, I strongly suggest that you browse through scientific journals in the science library and use these examples as an additional guide to help shape your laboratory write-ups.] References: Bacher, A.D., Organic Chemistry 30 BL Reader, Spring 2009, pg. 17-27 Bacher, A.D., A Short Survival Kit for the O=Chem lab, Spring 2009, pg. 147, 215