Reaktion #2336528

Reaktionsgleichung

phosgene

toluene

diisopropylethylamine

2-(4-chlorophenyl)ethylamine

3-hydroxypyridine-2-carboxylic acid

→

title compound

Ausbeute 70.5%

N-(2-(4-CHLOROPHENYL)ETHYL)-3-HYDROXYPYRIDINE-2-CARBOXAMIDE

Ausbeute 70.5%

Lösungsmittel

THF

ether

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeslowly rose to 0° C
2. 2
   Sonstigewas then recooled to −20° C.
3. 3
   workup.ADDITIONAfter the addition
4. 4
   workup.STIRRINGthe mixture was stirred an additional 2 hours as the temperature
5. 5
   Sonstigewas slowly brought to 0° C
6. 6
   workup.STIRRINGStirring
7. 7
   workup.WAITwas continued at 0° C. overnight
8. 8
   workup.ADDITIONTo this stirred mixture was added
9. 9
   Waschenwashed with 1N HCl (100 mL)
10. 10
    Trocknendried (MgSO4)
11. 11
    Einengenconcentrated

Vorschrift

A stirred mixture of 3-hydroxypyridine-2-carboxylic acid (1.39 g, 0.01 mol) in dry THF (60 mL) under argon was cooled to −20° C. To this was added all at once a 20% solution of phosgene in toluene (5.1 g, 0.01 mol) and the resulting mixture was stirred for 90 minutes while the temperature slowly rose to 0° C. The reaction mixture was then recooled to −20° C. and a solution of diisopropylethylamine (2.58 g, 0.02 mol) in THF (20 mL) was added dropwise over 30 minutes. After the addition was complete, the mixture was stirred an additional 2 hours as the temperature was slowly brought to 0° C. Stirring was continued at 0° C. overnight. To this stirred mixture was added, all at once, 2-(4-chlorophenyl)ethylamine (1.56 g, 0.01 mol), and the resulting mixture was stirred at room temperature for 6 hours. The mixture was diluted with ether (100 mL), washed with 1N HCl (100 mL), dried (MgSO4) and concentrated to give the title compound as an off-white solid (1.95 g). The mass spectrum showed the expected 3:1 parent ion ratio at m/e 276 and 278. COUPLING PROCEDURE B: PREPARATION OF 3-HYDROXY-4-METHOXY-N-(4-(4-TRIFLUOROMETHYLPHENOXY)PHENYL)-PYRIDINE-2-CARBOXAMIDE (425).

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