High-yield synthesis method of methyl 3-aminoisonicotinate
A technology of isonicotinic acid methyl ester and a synthetic method, which is applied in the field of chemical pharmacy, can solve the problems of high production energy consumption, low Hoffman degradation yield, high production cost, etc., and achieve high total yield, reduced production cost, and reaction The effect of mild conditions
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment 1
[0020] A high-yield synthetic method of 3-aminoisonicotinic acid methyl ester, such as figure 2 shown, including the following steps:
[0021] 1, Synthesis of 3-bromo-4-pyridinecarboxylic acid
[0022] Add 50g (0.41mol) of 4-pyridinecarboxylic acid and 150ml of methanol into the reaction flask, add 71.5g (0.45mol) of bromine dropwise while stirring at a controlled temperature of 20°C. At room temperature, filtered and dried to obtain 76.3 g of 3-bromo-4-pyridinecarboxylic acid, the yield was 93.5%, and the HPLC purity was 97.8%.
[0023] 2, Synthesis of 3-amino-4 pyridinecarboxylic acid
[0024] Add 50 g (0.25 mol) of 3-bromo-4-pyridinecarboxylic acid in batches to 100 ml of 18% ammonia water, add 1 g (0.0053 mol) of cuprous iodide, heat up to 100-105 °C in an autoclave and stir to react 6 hours, cooled to room temperature, adjusted the pH to 5.5-6 with 26% hydrochloric acid, filtered, and dried to obtain 32.1 g of 3-amino-4-pyridinecarboxylic acid with a yield of 93% and ...
Embodiment 2
[0029] A high-yield synthetic method of 3-aminoisonicotinic acid methyl ester, such as figure 2 shown, including the following steps:
[0030] 1, Synthesis of 3-bromo-4-pyridinecarboxylic acid
[0031] Add 50g (0.41mol) of 4-pyridinecarboxylic acid and 150ml of methanol into the reaction flask, add 64.9g (0.41mol) of bromine dropwise while stirring at a controlled temperature of 5°C. After filtering at room temperature and drying, 74.1 g of 3-bromo-4-pyridinecarboxylic acid was obtained, with a yield of 90.8% and a purity of 96.6% by HPLC.
[0032] 2, Synthesis of 3-amino-4 pyridinecarboxylic acid
[0033] Add 50g (0.25mol) of 3-bromo-4-pyridinecarboxylic acid in batches to 75ml of 18% ammonia water, add 0.48g (0.0025mol) of cuprous iodide, heat up to 100-105°C in an autoclave and stir to react 7 hours, cooled to room temperature, adjusted the pH to 5.5-6 with hydrochloric acid, filtered, and dried to obtain 30.7 g of 3-amino-4-pyridinecarboxylic acid with a yield of 89% a...
Embodiment 3
[0038] A high-yield synthetic method of 3-aminoisonicotinic acid methyl ester, such as figure 2 shown, including the following steps:
[0039] 1, Synthesis of 3-bromo-4-pyridinecarboxylic acid
[0040] Add 50g (0.41mol) of 4-pyridinecarboxylic acid and 150ml of methanol into the reaction flask, add 129.8g (0.82mol) of bromine dropwise while stirring at a controlled temperature of 30°C. After filtering at room temperature and drying, 78.6 g of 3-bromo-4-pyridinecarboxylic acid was obtained, with a yield of 96.3% and a purity of 97.6% by HPLC.
[0041] 2, Synthesis of 3-amino-4 pyridinecarboxylic acid
[0042] Add 50g (0.25mol) of 3-bromo-4-pyridinecarboxylic acid in batches to 125ml of 18% ammonia water, add 1.44g (0.0075mol) of cuprous iodide, heat up to 100-105°C in an autoclave and stir to react 8 hours, cooled to room temperature, adjusted the pH to 5.5-6 with 26% hydrochloric acid, filtered, and dried to obtain 32.9 g of 3-amino-4-pyridinecarboxylic acid, with a yield ...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More