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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

are nano particles real
Missy Reply
Hello, if I study Physics teacher in bachelor, can I study Nanotechnology in master?
Lale Reply
no can't
where we get a research paper on Nano chemistry....?
Maira Reply
nanopartical of organic/inorganic / physical chemistry , pdf / thesis / review
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
Application of nanotechnology in medicine
has a lot of application modern world
what is variations in raman spectra for nanomaterials
Jyoti Reply
ya I also want to know the raman spectra
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
Nasa has use it in the 60's, copper as water purification in the moon travel.
nanocopper obvius
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
analytical skills graphene is prepared to kill any type viruses .
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
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 .?
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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