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The addition of water causes the evolution of heat. An ice bath should be handy to cool the solution if it begins to reflux rapidly.

2. Now add 4-5 drops of 3 M HCl. Remove the vial, cap it, and stir it at room temperature for 5 min. Remove the vial from the stir plate and test the aqueous layer with litmus paper. The solution should be slightly acidic. Too much or too little aqueous HCl will cause problems in the subsequent workup procedure. Be careful in this step. NOTE: The water layer is the bottom layer. You will need to withdraw a few drops of the aqueous layer with a Pasteur pipette and drip it onto the litmus paper.

3. Remove the magnetic spin vane with forceps and set it aside to be rinsed with an ether wash. Cap the vial tightly, shake it, vent carefully, and allow the layers to separate.

4. Using a Pasteur pipette, transfer the aqueous (lower) layer to a clean 5.0 mL vial (see picture below). Save the ether layer since it contains the crude reaction product.


5. Now wash the aqueous layer that you have previously transferred to a 5.0-mL vial, with three 1.0-mL portions of diethyl ether:

6. Hold the magnetic spin vane with clean forceps and rinse it with the first portion of ether as it is added to the vial. Upon addition of each portion of ether (using a calibrated Pasteur pipette, see picture below), cap the vial, shake it (or use a Vortex mixer), vent carefully, and allow the layers to separate. With the aid of a Pasteur pipette, remove each subsequent ether (i.e. top) layer and combine it with the ether solution retained above. After the final extraction, do not forget to save the aqueous (lower) layer until you have isolated and characterized the final product.

NOTE: Pipette calibration: 1.0ml (diagram shows a previous version where we only used 0.5 mL. NOW we use 1.0 mL.) of ether which will give approximately 1.0 in height of solvent in the pipette above its "shoulder"

7. Extract the combined ether fractions with 2.0-mL of cold water to remove any acidic material.

8. Dry the ether solution by transferring it, using a Pasteur pipet, to a Pasteur filter pipet filled with 0.5g of anhydrous sodium sulfate. The elute is collected in a test tube. In the hood, remove the ether solvent from the elute by simply, putting the solution on an evaporation dish and allow the ether to evaporate.

Alternate Method of Removing Solvent: 1. Attach a Pasteur pipette to an air-line, turn the air on (gently) and place pipette in test tube to evaporate the ether (Ask TA for demonstration). 2. Gently warming the elute in a hot water bath to concentrate the solution to a weight less than 90 mg.

Part 4: purification and characterization

1. the product, 4-methyl-3-heptanol, will be used as is with no further purification. once all the solvent is gone, mass the product and the test tube (the mass of which has already been recorded). assuming no impurities, calculate the yield (remember, one of the reagents was taken in excess though).

2. Take this sample and dissolve in it in a small amount of methylene chloride (add 2 mL first then add 1 mL each time if you really need it). Prepare two TLC plates. On each plate spot both of the starting materials as well as the product mixture and standard provided by TA (i.e. four spots on each plate). Run one TLC plate in 100% Methylene Chloride, the other in 1:9 ethyl acetate: hexane. Record both plates under UV light and with the p-Anisaldehyde stain.

3. Calculate the R f size 12{R rSub { size 8{f} } } {} of all of the compounds for both plates. Draw TLC plates in the notebook.

4. One sample will be taken for NMR and GC-MS studies.

Waste disposal

Syringes and needles are to be disposed separately. Needles will go into the Sharps waste basket and syringes in the waste basket. Pipettes should not go into the Sharps waste basket. Organic and inorganic waste should be disposed in their proper containers.Approximate Lab time: 2-2.30 hours

Report Questions (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. Explain why Grignard reagents cannot be prepared from an organic halide that also contains a hydroxyl (-OH), a carboxyl ( CO 2 H size 12{ - ital "CO" rSub { size 8{2} } H} {} ), a thiol (-SH), or an amino ( NH 2 size 12{ - ital "NH" rSub { size 8{2} } } {} ) group. (2 points)

2. Why does the 2-bromopentane not appear under UV light for TLC? (2 points)

3. Draw and show your R f size 12{R rSub { size 8{f} } } {} calculations for each TLC run. Which solvent was better? (3 points)

4. Show your theoretical and percent yield calculations. (4 points)




5. Draw the structure of your product and assign a proton to each peak in your NMR spectrum. Try and determine, if any, the impurities are in the sample. (4 points)

6. An NMR and GC-MS of the product are provided. What information can you obtain from the GC-MS? (5 points)

7. Write the major product of the following reactions: (10 points)

8. Identify the compounds (A-F). (Extra credit 6 points)

Questions & Answers

what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
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.
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
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
characteristics of micro business
for teaching engĺish at school how nano technology help us
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
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
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.
what is the actual application of fullerenes nowadays?
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.
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.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
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.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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