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Experimental procedure

1. Place 0.25 g. of ferrocene in a 10 mL round-bottom flask containing a magnetic stir bar. Prepare a hot water bath by heating the water to nearly the boiling point while preparing the following reaction mixture.

2. In a fume hood, add 1.0 mL of acetic anhydride and 0.15 mL of 85% phosphoric acid to the flask. The reaction mixture should heat up and darken in color. Swirl the flask, heating occasionally in a hot water bath if necessary, until all the ferrocene dissolves.

3. Attach a reflux condenser then heat the reaction mixture with stirring in the hot water bath prepared in step 1. Heat the mixture for 10 minutes during which time a purple color may develop.

Workup and purification:

4. Pour the reaction mixture onto 2 or 3 cubes of ice in a 400 mL beaker, then rinse the flask with two 5 mL portions of ice water. (A black residue may remain in the flask.) Stir the orange-brown mixture with a glass rod for a few minutes. Any insoluble black material present will be removed in the following steps.

5. Add 6.0 mL of 3 M aqueous NaOH solution, then carefully add solid sodium bicarbonate in small portions until the remaining acid has been neutralized (about 2-3 grams). Use great care to avoid excessive foaming during bicarbonate addition. This step can be done with magnetic stirring, but make sure to use a stirring plate that is not hot. Stir well and crush any lumps to afford a dark-brown suspension.

6. Allow the mixture to stand for 20 minutes, and then collect the crude product by vacuum filtration. Continue to pull air through the product for a few minutes to dry it. Finish the drying process by pressing the solid product between two sheets of filter paper or paper towels. Save some of this crude product for TLC analysis.

7. Transfer the solid and a stir bar to a 50 mL beaker and add 10 mL of hexanes. Boil for 5 minutes with stirring, and then decant the dark-orange solution into another Erlenmeyer flask leaving behind a black gummy substance. If you boil off all the liquid, try again with another 10 mL of hexane and lower heat.

8. To the hot solution, add a spatula-full of decolorizing carbon (If you use too much, you will reduce your yield of carbon). Heat with swirling, and then perform a hot filtration to remove the decolorizing carbon.

9. Set the flask aside to cool slowly. Red-brown needles of acetylferrocene should begin to form. Once the flask has reached room temperature, cool it in ice. Collect the crystalline product by vacuum filtration and washing with a small quantity of cold hexane, then dry by continuing to pull air through the product for a few minutes. If you add to much cold hexane here, you will lose your product.

Characterization:

10. Record the yield and melting point range for your recrystallized acetylferrocene.

11. Analyze your crude and recrystallized products by TLC. Separately dissolve very small amounts of pure ferrocene, the crude product, and the recrystallized acetylferrocene in a few drops of toluene. Spot the solutions on silica gel plates and develop with 30:1 toluene/absolute ethanol. Visualization is simple as each compound is brightly colored.

Safety

Wear safety goggles and gloves all the time.

Waste disposal

Organic compounds must be disposed in the proper container.

Approximate lab time 2 – 2 ½ hours

Report 4: friedel- crafts

(Total 30 points)

(Click here for the Report Form

Note: In preparing this report you are free to use references and consult with others. However, you may not copy from other students’ work or misrepresent your own data (see honor code).

Name(Print then sign): ___________________________________________________

Lab Day: ___________________Section: ________TA__________________________

1. Draw the mechanism for the reaction of ferrocene, acetic anhydride, and phosphoric acid. (6 points)

2. Show your theoretical and percent yield calculations for the reaction. (3 points)

 

 

3. The melting point of your re-crystallized acetylferrocene is: ---- (2 points)

4. Draw the TLC plates and show your R f size 12{R rSub { size 8{f} } } {} calculations (4 points)

5. Classify each of the following species as anti-aromatic, aromatic, or nonaromatic.

Support your answer. (4 points)

6. Ordinarily the barrier to rotation about a carbon-carbon double bond is quite high (40

kcal/mol), but the compound below was observed to have a rotational barrier of only about 20 kcal/mol. Explain this result. (3 points)

7. Propose a mechanism for the following reaction. (8 points)

Questions & Answers

anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Chem217labsfall07. OpenStax CNX. Oct 16, 2007 Download for free at http://cnx.org/content/col10463/1.4
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