[Stewed_ant]

 

First of all, i'd like to say that our lecturer hasn't even put in a single tutorial to help us understand mechanisms in general. 

Please if anyone would enjoy tutoring a very open minded and eager student ! you know who to send a message to!

Anyway now for the question. Can i get some help with this organic lab right up.

1.Creation of Vanadium(IV) Acetylacetonate, -  Disolved VOSO4.5H2O in water, added acetylacetone, got blu-green solid, add NaOH and water to get deep blue persipitate then washed with a small amount of acetone.

2. Creation of Copper(II) Acetylacetonate - Disolved Copper(II) Chloride in H2), added concentrated aqueous ammonia till clear deep blue soln results. Added  2ml acetylacetone, and mix till blue percipitate is complete.

What are the mechanisms and equations that are actually going on here?

[Stewed_ant]

Heeelp!

[movies]

Do you know what the products of these reactions look like?

What has changed about the acetylacetone part?

Why would you add NaOH or NH₃ to these reactions?

[Winga]

1.
NaOH is a base, acetylacetone is an acid.
Acetylacetone will be deprotonated to form acetylacetonate. (Which H⁺?)

[Stewed_ant]

Do you know what the products of these reactions look like?

 deep blue persipitate and light blue percipitate as in question.

Why would you add NaOH or NH3 to these reactions?

That's what it said to do in teh lab manuel.

[AWK]

First of all, i'd like to say that our lecturer hasn't even put in a single tutorial to help us understand mechanisms in general. 

Please if anyone would enjoy tutoring a very open minded and eager student ! you know who to send a message to!

Anyway now for the question. Can i get some help with this organic lab right up.

1.Creation of Vanadium(IV) Acetylacetonate, -  Disolved VOSO4.5H2O in water, added acetylacetone, got blu-green solid, add NaOH and water to get deep blue persipitate then washed with a small amount of acetone.

2. Creation of Copper(II) Acetylacetonate - Disolved Copper(II) Chloride in H2), added concentrated aqueous ammonia till clear deep blue soln results. Added  2ml acetylacetone, and mix till blue percipitate is complete.

What are the mechanisms and equations that are actually going on here?

At the beginning you did simple double exchange ionic reactions. In the first case you got probaly vanadyl acetoacetonate as the first step, and after addition NaOH V(acac)2 precipitated.
In the second case you obtained copper acetylacetonate from copper ammonia complex.

After the double exchange reaction, metal-oxygen covalent bond is formed followed by a chelation of metal with the second oxygen of acetylacetonate

[Stewed_ant]

Thanks ! !

Which means what was right!


Also does anyone know what are the effects of meling vanadium (IV) acac and Copper(II) acac ? What happens if you disolve them in H20 and dichloromethane?

For instance i disolved COBOLT (III) acac in dichloromethane and got a green soln. But after melting it, i dissolved it CH2CL2 and got a brown soln.

What's the chemistry behind what happened here?

[AWK]

http://www.uark.edu/depts/cheminfo/uarkchem/undergraduate/courseinformation/Chem1121/Metal%20Complexes%20of%20Trifluoropentanedione.pdf