ChemicalBook CAS DataBase List 2-Amino-4-chloropyridine

2-Amino-4-chloropyridine synthesis

10synthesis methods

Product Name:2-Amino-4-chloropyridine
CAS Number:19798-80-2
Molecular formula:C5H5ClN2
Molecular Weight:128.56

Methyl 4-chloropicolinate hydrochloride in methanol was treated with hydrazine hydrate, resulting in the formation of a precipitate. The suspension was then stirred for 2 hours and the precipitated hydrazide was collected through filtration. The hydrazide was dissolved in 1N hydrochloric acid and the solution was cooled to a temperature between 0-5 ℃. A solution of sodium nitrite in water was then added dropwise, causing another precipitate to form. After stirring for 15 minutes, the precipitate was collected by filtration and washed with water. The moist precipitate was then combined with a mixture of acetic acid and water, and the resulting solution was heated in a steam bath until gas evolution stopped. The reaction mixture was cooled to room temperature, the pH was adjusted to 7, and the resulting precipitate was collected via filtration. Recrystallization using ethanol yielded 2-Amino-4-chloropyridine in the form of a white crystalline solid[1].

(4-CHLORO-PYRIDIN-2-YL)-CARBAMIC ACID TERT-BUTYL ESTER

130721-78-7
139 suppliers
$9.00/100mg

19798-80-2
547 suppliers
$6.00/1g

Yield:19798-80-2 100%

Reaction Conditions:

with hydrogenchloride in 1,4-dioxane at 20; for 18 h;

Steps:

32 Synthesis of 4-Chloropyridin-2-amine (compound 65-2)

Synthesis of 4-Chloropyridin-2-amine (compound 65-2)[0000228] To a stirred solution of tert-butyl 4-chloropyridin-2-ylcarbamate (2 g, 8.7 mmol, 1 equiv) was addeda 4N solution of hydrogen chloride in dioxane (10 mL, 40 mmol,4.6 equiv) . The solution was allowed to stir for 18 hours atroom temperature. The reaction was concentrated under reduced pressure to give compound 65-2 (HC1) as a reddish yellow solid (1.5 g, 100% yield)

References:

WO2013/123215,2013,A2 Location in patent:Paragraph 0000228

99586-65-9 Synthesis