Furfural $(\ce{C5H4O2})$ has been used as a feedstock for synthesis. Furfurylamine $(\ce{C5H7NO})$ is made from furfural.

Given that industrial manufacturing ammonia is matured, how about combining furfural, ammonia and hydrogen to directly synthesize pyridine? Is the following reaction realizable?

$$\ce{C5H4O2 + NH3 + H2 -> C5H5N + 2 H2O}$$

Both furfural and pyridine are significant organic compounds. If one compound can be made from the other, the cost of the other can drop. So far is how pyridine itself is being manufactured remained an industrial secret? Substituted pyridines are covered in many articles and online information.

Wikipedia pyridines production indicates that

  1. Chichibabin synthesis makes dihydropyridine, a pyridine derivative from acrolein, acetaldehyde and ammonia and byproducts are observed.
  2. Bönnemann cyclization of acetonitrile and two molecules of acetylene gives 2-methylpyridine, a substituted pyridine. Following dealkylation gives pyridine.

In essence, substituted or derived pyridines were first made in multisteps and they are further processed to the parent pyridine.

Another possible route would be using the aza variety of the Achmatowicz reaction on furan.

  1. Hydrogen replaces Ts(hydrogen replaces Ts) and removing of hydroxyl and alkyl make the parent pyridine.
  2. (enter image description here removing the hydroxyl makes the parent pyridine.

Still, substituted furfurylamines $(\ce{C5H7NO})$ is needed at the beginning. In other words, my question was about if as few steps as possible making the parent pyridine from a prevalent starting material such as furfural is realizable.

  • $\begingroup$ This approach tends to give 3-hydroxypyridines $\endgroup$
    – Waylander
    Mar 22 at 19:33
  • $\begingroup$ $$\ce{C5H4O2 + NH3 -> C5H5NO + H2O}$$ 2 or 3 or 4-hydroxypyridines do not matter if the hydroxypyridine can be hydrogenated to pyridine and water. $$\ce{C5H5NO + H2 -> C5H5N + H2O}$$ $\endgroup$
    – Kav
    Mar 22 at 19:55
  • $\begingroup$ if your first step is to make furfurylamine then treat with hydrogen peroxide and HCl researchgate.net/publication/… $\endgroup$
    – Waylander
    Mar 22 at 19:58
  • $\begingroup$ 3-hydroxypyridine behaves much like phenol so good luck with trying to reduce it by hydrogenation. $\endgroup$
    – Waylander
    Mar 22 at 19:59
  • $\begingroup$ That is one reason I want to ask... I can be flawed and wrong in lines of thought. $\endgroup$
    – Kav
    Mar 22 at 20:04

I do not know whether the following is a real answer or not but Wikipedia 3-methylpyridine article shows

3-Methylpyridine is produced industrially by the reaction of acrolein with ammonia: :$$\ce{2 C3H3O + NH3 -> 3-CH3C5H4N + 2 H2O}$$ This reaction also affords substantial amounts of pyridine.

Wikipedia Nicotinonitrile article

A colorless solid, it is produced by ammoxidation of 3-methylpyridine:[2]. Nicotinonitrile is a precursor to the vitamin niacin.

In other words, the question could become one of separating pyridine from 3-Methylpyridine.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.