Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
 Pages:  1  2
Author: Subject: New Amateur Way to Prepare Pyridine

Posts: 4
Registered: 3-4-2013
Member Is Offline

Mood: No Mood

[*] posted on 13-4-2013 at 20:34

That's exactly what I mean, but also there's another alternative that you can buy from farm supply and feedstock a 25kg bag Niacin for $21 per KG. if you buy of eBay they sells around $30 for 500g. regards the Hooka I've one that the water not been changed and not it's a very dense and dark looking. I mean after around 6 months used. lol

but believe the main point is not Niacin and most important are other intransigents.
View user's profile View All Posts By User
Hazard to Others

Posts: 118
Registered: 14-1-2012
Location: Europe
Member Is Offline

Mood: Desiccated

[*] posted on 30-12-2013 at 09:29

To expand upon the work done by member "ubungy". I attempted the Prep. of pyridine using both basic copper(II) carbonate and copper(II) oxide as the precatalysts.
Use of CuCO3.Cu(OH)2 causes some water contamination in the obtained pyridine but can be removed with NaOH.
My first runs overdid the heating... just a tad.

Preparation with basic copper(II) carbonate.

Into a 250ml RBF was added an intimate mixture of 30g niacin (244mmol) and 26.9g CuCO3.Cu(OH)2 (122mmol) and the mixture was heated on a hotplate on full power (plate surface Temp. 480°C), internal Temp. was unmonitored. Heat transfer to the flask was aided with a stainless steel scouring pad 'nested' between the flask and hotplate.
In total 19ml yellow liquid was collected.
The residue in the RBF appeared to consist of mostly of a black powder (possibly CuO) containing some Cu0 that broke apart into a fine dust upon shaking the flask, a partial copper mirror had formed on the very bottom of the flask.

The reaction above was repeated with a smaller proportion of copper carbonate.
50g Niacin (406mmol) and 12g CuCO3.Cu(OH)2 (54mmol, 13%mol) was heated as above.
28ml of yellow liquid was collected.
As the reaction progressed a stream of a white vapor was carried along with the CO2 that was possibly subliming niacin.
This time the residue in the flask left some hard black organic crap stuck to the walls but was removed most easily by soaking with aqueous H2SO4 for a few hours (NaOH did not appear to touch it).

Treatment of the distillates above with NaOH formed a voluminous salt in suspension occupying about half the visible volume. Both distillates were combined and the whole was distilled to collect a clear colorless liquid. The distillate was treated with ~2g of NaOH and stirred for ~0.5hrs. The upper pyridine phase was separated from the
lower aqueous phase and re-distilled to give 35ml (68% overall yield) of pyridine.

The last run above with 50g of niacin was repeated but with more cautious heating. Heating was slowly brought up to temperature
until distillation began (plate surface Temp. ~350°C). The 27ml of very pale yellow distillate obtained (~3hrs) was re-distilled to remove niacin by putting it
back into the cooled reaction flask with the black residue and distilling normally (aspirator vacuum to pull the last of it over),
dried over 1g NaOH, separated and re-distilled to give 25ml (78% yield) of pyridine.
While a slightly smaller volume was initially collected than the previous run it contained less niacin.


Near identical results were obtained when CuO was used instead, although the distillate contained less H2O.

It appears that both basic copper carbonate and copper(II) oxide are adequate substitutes for the copper chromite catalyst.

When larger amounts of catalyst were used (i.e. equimolar Cu to niacin) residue cleanup was much easier.
View user's profile View All Posts By User
 Pages:  1  2

  Go To Top