Method of obtaining nicotinic acid

Organic compounds -- part of the class 532-570 series – Organic compounds – Heterocyclic carbon compounds containing a hetero ring...

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

546327, 546319, C07D213127, C07D21380, C07D21379, C07D213803

Patent

active

057288372

DESCRIPTION:

BRIEF SUMMARY
CROSS-REFERENCE

This application is a 371 of PCT/RU95/00013 filed Jan. 26, 1995.


FIELD OF THE INVENTION

The invention relates to a process for preparing nicotinic acid. Nicotinic acid and its derivatives have a wide variety of physiological properties, due to which they are widely used in medicine and agriculture as vitamins, drugs, and growth regulators for plants.


BACKGROUND OF THE INVENTION

Several processes for synthesis of nicotinic acid are known: 1) By liquidphase oxidation of .beta.-picoline using as the oxidant KMnO.sub.4 (M. R. Rubtsov, L. N. Yakhontov, S. V. Yatsenko, ZhPKh, 1957, v, 30, No. 2, pp. 315-318), and also HNO.sub.3 and H.sub.2 SO.sub.4 (U.S. Pat. No. 2,586,555, 1952); 2) By oxidative ammonolysis of .beta.-picoline in the presence of a vanadium catalyst with subsequent hydrolysis of nicotinonitrile into nicotinic acid (USSR Inventor's Certificate No, 235764, published B.I. No. 6, 1969).
Liquid phase oxidation of .beta.-picoline using the oxidants indicated above takes place at a high selectivity at a temperature of 75.degree.-300.degree. C. The yield of nicotinic acid in such processes is 66-77%. Substantial drawbacks of these processes include their periodicity, multistage execution, complexity of technological execution, low productivity, large amount of waste water and solid wastes containing harmful substances.
The preparation of nicotinic acid through oxidative ammonolysis of .beta.-picoline is carried out at a temperature of 350.degree.-400.degree. C. with a high productivity and a high yield (86-88%), but includes many steps, in particular, liquid products of the reaction;
The process is also characterized by a large number of harmful liquid wastes and waste gases comprising ammonia.
One more process for preparing nicotinic acid is known (Sven Jaras, Sten T. Lundin. Preparation of pyridinemono-carboxylic acids by catalytic vapor phase oxidation of alkylpyridinel.--J.Appl. Chem. Biotechnol., 1977, 27 pp.499-509). According to this process nicotinic acid is prepared by direct single step gas-phase oxidation of .beta.-picoline with oxygen in the presence of nitrogen and an aqueous vapor on an oxide catalyst located in a tubular reactor. Wherein the reaction temperature is 350.degree.-460.degree. C., space velocity of the gaseous mixture is 1450-2600 h.sup.-1 (contact time is 2.5-1.4 s), mole ratios O.sub.2 :.beta.-picoline=42, H.sub.2 O: .beta.-picoline=82. The catalyst is prepared by melting a mixture of V.sub.2 O.sub.5 and TiO.sub.2 at a temperature of 1250.degree. C. in the course of 3 hours. The specific surface of the catalyst thus prepared is 0.2-1.0 m.sup.2 /g. Granules having a size of 0.5-1.5 mm are loaded into a reactor. When the process is carried out under these conditions the maximum yield of nicotinic acid is 48%. Products of the reaction are, in addition to nicotinic acid, .beta.-pyridine carbaldehyde, pyridine, CO, CO.sub.2 and HCN. Harmful waste gases comprising CO and HCN are formed in the reaction process. The nicotinic acid is gathered in a condensate comprising, furthermore, unreacted .beta.-picoline, 3-pyridine carbaldehyde, pyridine and resin-like products. The isolation of nicotinic acid from the condensate is carried out using a complex multistage process including extraction of .beta.-picoline and .beta.-pyridine carbaldehyde with chloroform from an aqueous solution with the subsequent isolation of nicotinic acid from the aqueous phase. Wherein liquid harmful wastes are formed which need to be recovered, and the nicotinic acid may be contaminated by chloroform ingredients which makes purification more difficult.
The data provided above show that the described process has the following drawbacks: making its isolation and purification more difficult, are formed in the process of preparing nicotinic acid;
Therefore, the existing processes of preparing nicotinic acid are characterized by a large number of harmful liquid wastes and gas wastes, by the formation of resin-like products, and with single-step oxidation of .beta.-picoline by the low yield of

REFERENCES:
patent: 2586555 (1952-02-01), Mueller
patent: 4001257 (1977-01-01), Masuda et al.
Rubtsov, M.V., et al. "Preparation of Nicotonic . . . " Short Notices pp. 315-317. (in Russian w/English translation) 1957.
Jaras, Sven, et al. "Preparation of Pyridinemonocarboxylic . . . " J. Appl. Chem. Biotechnol. 1977, 27, pp. 499-509.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Method of obtaining nicotinic acid does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method of obtaining nicotinic acid, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of obtaining nicotinic acid will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-958854

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.