The Production Process of tert-butyl 5-bromo-3-hydroxypyridin-2-ylcarbamate

The Production Process of Tert-Butyl 5-Bromo-3-Hydroxypyridin-2-Ylcarbamate in the Chemical Industry

In the chemical industry, the production of tert-butyl 5-bromo-3-hydroxypyridin-2-ylcarbamate (CAS 174677-12-4) is a highly complex process that involves several steps and various intermediates.
This article will provide an overview of the production process for tert-butyl 5-bromo-3-hydroxypyridin-2-ylcarbamate, highlighting the key steps involved in the synthesis of this compound.

Step 1: Preparation of Bromoacetate

The production of tert-butyl 5-bromo-3-hydroxypyridin-2-ylcarbamate begins with the preparation of bromacetate, which is a common reagent used in organic synthesis.
Bromoacetate is prepared by the reaction of bromine with acetic acid in the presence of a catalyst such as pyridine or collidine.
The reaction produces bromoacetate, which is then purified by conventional methods such as filtration and distillation.

Step 2: Condensation of Bromoacetate and Phenyl Acetate

The next step in the synthesis of tert-butyl 5-bromo-3-hydroxypyridin-2-ylcarbamate is the condensation of bromoacetate and phenyl acetate in the presence of a strong acid catalyst such as sulfuric acid.
This reaction produces a mixture of phenyl bromide and bromoacetate, which is then treated with a strong base such as sodium hydroxide to produce a phenylated derivative of bromoacetate.

Step 3: Dehydration of the Phenylated Bromoacetate

The phenylated derivative of bromoacetate produced in the previous step is then dehydrated to produce 4-bromophenol.
This is typically achieved through the use of a dehydrating agent such as sulfuric acid or phosphorous oxychloride, which removes water from the reaction mixture to produce 4-bromophenol.

Step 4: Ring Closure Reaction

The next step in the synthesis of tert-butyl 5-bromo-3-hydroxypyridin-2-ylcarbamate is the ring closure reaction, which involves the reaction of 4-bromophenol with a compound such as phenylboronic acid or 4-bromo-3-pyridinecarboxylic acid.
This reaction produces a phenyl-substituted derivative of pyridine-3-carboxylic acid.

Step 5: Nitration of the Phenyl-Substituted Pyridine-3-Carboxylic Acid

The phenyl-substituted derivative of pyridine-3-carboxylic acid produced in the previous step is then nitrated using nitric acid to produce 4-nitrophenyl-substituted derivative of pyridine-3-carboxylic acid.
This reaction typically involves the use of a solvent such as toluene and a catalyst such as iron(III) chloride.

Step 6: Reduction of the Nitro Derivative

The next step in the synthesis of tert-butyl 5-bromo-3-hydroxypyridin-2-ylcarbamate is the reduction of the nitro derivative produced in the previous step using a reducing agent such as sodium borohydride.
This reaction reduces the nitro group to