SU1553531A1 - Method of producing pyridine-4-carboxamide - Google Patents

Abstract

The invention relates to heterocyclic substances, in particular the preparation of pyridine-4-carboxamide, a plant growth regulator used in agriculture. The goal is to increase productivity and simplify the process. The latter is carried out by hydrolysis of 4-cyanopyridine in the presence of NAOH and water at a molar ratio of 1: 0.03 - 0.075: 4-7 and 120-170 ° C for 5-20 minutes. These conditions increase the yield of the target product to 97% with a capacity of 3.3 - 12.6 kg / l water, which is 600 - 900 times higher than in the known case.

Description

The invention relates to an improved method for the preparation of pyridine-4-carboxamide, which is used as a plant growth regulator.

The aim of the invention is to simplify the process and increase its productivity by hydrolyzing 4-cyanopyridine with aqueous alkali at a molar ratio of nitrile sodium: water equal to 1: (0.03-0.075): (4-7) and temperature 120- 170 ° C for 5-20 min. /

Example 1. 1 g (0.0096 mol) of 4-cyanopyridine, 0.0192 g (0.00048 mol) of caustic soda and 0.87 g (0.0481 mol) of water (molar ratio nitrile alkali; water 1: 0, 05; 5) placed in a stainless steel autoclave and heated at 150 ° C for 10 minutes. According to a polarographic analysis, the hydrolyzate contains 1, 1378 g (0.0093 mol) pyridine-4-carboxamide (isonicotin amide). Yield 97% based on the taken nitrile. Isonicotipamide, obtained in the form of a white solid precipitate, is filtered off by washing with distilled water. After drying, 0.9971 g (0.0081 mol) of isoniquinamide with m.p. 154-155 C. The release of release amide is 85% of the theoretically possible, based on the starting 4-cyanopyridine. Process productivity 7.9 kg / l H2O h.

Example 2. The method is carried out as described in Example 1. 2 g (0.0122 mol) of 4-cyanpyridine, 0.0385 g (0.00096 mol) of sodium hydroxide and 2.08 (0.1153 mol) of water (molar . The ratio of nitrile: alkali scrubber 1: 0.05: 6) is heated for 9 minutes at 150 ° C. Get 2,2710 g (0,0186 mol) of isonicotinamide, vydЈ3SSS

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move 96.8%. Process productivity 7.3 kg / l Н20 h.

Example 3. The method is carried out as described in Example 1. 1 g (0.0096 mol) of 2-cyanopyridine, 0.0192 g (0.00048 mol) of sodium hydroxide and 1.04 g (0.0577 mol) of water (molar ratio nitrile alkali: water 1: 0.05: 6) is heated for 10 minutes at 120 ° C. Obtain 1,0558 g (0,0086 mol) of isonicotinamide, yield 90.0%. Productivity of process is 6,1 kg / l,

Example 4. The method is carried out according to Example 1. 1 g (0.0096 mol) of 4-cyanpyridine, 0.0192 g (0 00048 mol) of caustic soda and 1 „04 g (0.0577 mol) of water (molar The ratio of nitrile: alkali: water 1: 0 „05 .6) is heated at 140 ° C for 10 minutes. This gives t, 0933 g (0.0089 mol) of isonicotinamide, yield 93 ± 2%. .Process performance of 6.3 kg / lh

Example 5 The method is carried out as described in Example 1. 1 g (0.0096 mol) of 4-cyanopyridine, 0.0192 g (0.00048 mol) of sodium hydroxide, 0.0086 g (0.00048 mol) of water (molar the ratio of nitrile-alkali: water is 1; 0.05: 5) is heated at 160 ° C for 10 minutes. 1.1390 g (0.0093 mol) of isonicotinamide are obtained, yield 97.1%. Process productivity 799 kg / l Н20 h.

Example 6. The method is carried out as described in Example 1. 2 g (0.0122 mol) of 4-cyanopyridine, 0.0384 g (0.00096 mol of sodium hydroxide, 2.08 g (0.1154 mol) of water (molar ratio nitrile : Alkaline oil 1: 0.05: 6) is heated for 10 minutes at 170 ° C. 2.28 g (0.0186 mol) of isonicotinamide are obtained, yield 97.2%. Productivity of the process is 6.6 kg / l H40 —h.

Example 7. Sposeb was carried out as described in Example 1. 1 g (0.0096 mol) of 4-cyanopyridine, 0.01115 g (0.00028 mol) of sodium hydroxide, 1.04 g (0.0577 mol) of water (molar the ratio of nitrile: alkali: water 1: 0.03: 6) is heated for 10 minutes at 150 ° C. 190569 g (0.0086 mol) of isonicotinamide are obtained, yield 90.1%. Process productivity 6.1 kg / l HjO-h.

Example 8. The method is carried out as described in Example 1. 1 g (0.0096 mol) of 4-α-cyanopyridine, 0.0153 g (0.00014 mol of sodium hydroxide, 1.04 g (0.0577 mol) of water (molar ratio nitrile alkali: water 1: 0.04: 6) heat

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10 min at 150 ° C. Get 1,0698 g (0,0887 mol) of isonicotinamide, the output of 91.2%. Productivity of the process is 6.2 kg / l H40 “h.

Example 9. The method is carried out as described in Example 1. 1 g (0.0096 mol) of 4-cyanopyridine, 0.0230 g (0.00018 mol) of sodium hydroxide, 1.04 g (0.0577 mol) of water (molar ratio nitride: alkali: water 1: 0.06: 6) is heated for 10 minutes at 150 ° C. G (0.0091 mol) of 4-cyanopyridine is obtained, yield 94.2%. Process performance 6.4 kg / l NgO H.

Example 10. The method is carried out as described in Example 1. 1 g (0.0096 mol) of 4-cyanopyridine, 0.0288 g (0.00072 mol) of sodium hydroxide and 0.86 g (0.0480 mol) of water (molar ratio nitrile: alkali: water 1: 0.075: 5) is heated, 10 minutes at 150 ° C. 1.0240 g (0.0084 mol) of isonicotinamide are obtained, yield 87.3%. Productivity 7.1 kg / l Hj, 0. h

Example 11. The method is carried out as described in Example 1. i g (0.0096 mol) of 4-cyanopyridine, 0.0192 g (0.00048 mol) of sodium hydroxide and 0.70 g (0.0384 mol) of water (molar ratio nitrile:: alkali: water 1: 0.05: 4) is heated for 10 minutes at 150 ° C. 1.05 g (0.0086 mol) of isonicotinamide are obtained, yield 89.7%. Productivity is 5,2 kg / l

Example 12. The method is carried out as in Example 1, 1 g (0.0096 mol) of 4-cyanopyridine, 0.0192 g (0.00048 mol) of sodium hydroxide, 1.20 g (0.067 mol) of water (molar ratio nitrile: : alkali: water 1: 0.05: 7) is heated for 10 minutes at 150 ° C. 1.14 g (0.093 mol) of isonicotinamide are obtained, yield 97.2%. “Productivity 5.6 kg / l.

Example 13. The method is carried out as described in Example 1. 1 g (0.0096 mol) of 4-cyanopyridine, 0.0192 g (0.00048 mol) of alkali and 1.00 g (0.0056 mol) of water (molar ratio nitrile gheloche: water 1: 0.05: 5.8) is heated for 5 minutes at 150 ° G. Obtain 1,0557 g (0,0086 mol) of isonicotinamide, yield 90.0%. Productivity is 12,6 kg / l.

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Example 14. The method is carried out as described in Example 1. 2 g (, 0.0192 mol) of 4-cyanopyridine, 0.0384 g (0.0096 mol)

caustic soda and 2.08 g (0.11548 mol) of water (molar ratio of nitrile: alkali: water 1: 0.05: 6) is heated for 20 minutes at 150 ° C. 1.1390 g (0.0093 mol) are obtained .. i-eonicotinamide, yield 97.1%. Productivity of the process is 3.3 kg / l. . In this way, the method allows to obtain pyridine-4-carboxamide with vy-. running up to 97% with a productivity of 3.3-12.5 kg of the target product per 1 liter of water per hour, which is 600-900 times higher than in the prototype method.

Claims (1)

Claims. The method of producing pyridine-4-carboxamide by alkaline hydrolysis of 4-cyanopyridine with heating, characterized in that, to simplify the process and increase its productivity, caustic soda is used as the alkaline agent and the process is carried out at a molar ratio of nitrile: caustic soda: zod 1: (0.03-0.075) :( 4-7) and 120-170 ° C for 5-20 minutes.