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Part 1:

Preparation of 1-methylbutyl magnesium bromide:

1. Prepare a 5.0 mL conical vial containing a magnetic spin vane and equipped with a condenser. Weigh and place 75 mg (approximately 3-4 pellets) of magnesium in the vial, and then add a small crystal of iodine (Do not add excess iodine), followed by 500 µL of anhydrous ether.

NOTE: Metal magnesium you will be provided with has a coil shape and has been cut into small pieces. This material should be handled with forceps only. Four to five small pieces of Mg weigh about 75 mg.

NOTE: Plastic syringes tend to get stuck when filled with ethyl ether. Be ready to push a bit harder on a syringe plunger when adding liquid to the reaction mixture.

2. Prepare a solution of 520 µL of 2-bromopentane in 600 µL of anhydrous diethyl ether in a dry 5 mL conical vial. Use a syringe to deliver each solution. TA will do that.

3. After the assembly has cooled to room temperature, then draw the 2-bromopentane solution into a 1.0-mL syringe and then insert the syringe needle through the rubber septum on the top of the condenser. (Do not heat the closed system, it may explode!!!!)

4. While stirring the heterogeneous mixture, slowly add 6-8 drops of the 2-bromopentane ether solution to initiate the formation of the Grignard reagent. The evolution of tiny bubbles from the surface of the magnesium is evidence of a reaction.


5. When the reaction has started, slowly add the remainder of the 2-bromopentane-ether solution drop wise over a 3 to 5-min period. Warm the reactants slightly. Upon completion of this addition, draw the rinse in the capped vial into the syringe and add it through the septum in a single portion to the reaction vial. Stir the resulting solution for 15 min.


Do not overheat. Overheating will cause loss of ether solvent. (The b.p. of ether is 34.6 °C.) Small fragments of magnesium may remain at the end of the addition of the alkyl halide.

6. Cool the gray-colored solution of Grignard reagent to room temperature.

Preparation of propanal (propionaldehyde)

1. Prepare a solution of the aldehyde by weighing 100 µL of propanal into a tared, oven-dried, 3 mL conical vial followed by the addition of 200 µL of anhydrous diethyl ether. Cap the vial after solution is ready. The propanal is the limiting reagent and therefore an accurate weight should be recorded for the yield calculations. TA

Part 2: grignard reaction

1. Now add the propanal solution carefully, with stirring, to the Grignard reagent over a period of about 30 sec at such a rate as to keep the ether solvent at a steady reflux.

2. Rinse the vial that contained the propanal solution with 100 µL of anhydrous diethyl ether and add to the Grignard reagent. This step insures that all the propanal is added to the Grignard reagent.

3. Stir the reaction mixture for 5 min and then allow it to cool to room temperature. Remove the conical vial and take off the cap. It is recommended that the vial be placed in a beaker to prevent tipping and loss of product.

Part 3: isolation of product

1. Hydrolyze the magnesium alkoxide salt by addition of 2.0 mL of water. Stir the resulting mixture for 5 min. A two-phase (ether-water) reaction mixture develops as the magnesium salt is hydrolyzed. Remove any unreacted magnesium.

Questions & Answers

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.
what is biological synthesis of nanoparticles
Sanket Reply
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