Name | 5,7-Dichloro-1,6-naphthyridine |
Synonyms | SKL321 5,7-Dichloro-1,6phthyridine 5,7-dichloro-1,6-naphthyridine 5,7-Dichloro-1,6-naphthyridine 1,6-Naphthyridine,5,7-dichloro- |
CAS | 337958-60-8 |
EINECS | 691-542-2 |
InChI | InChI=1/C8H4Cl2N2/c9-7-4-6-5(8(10)12-7)2-1-3-11-6/h1-4H |
Molecular Formula | C8H4Cl2N2 |
Molar Mass | 199.04 |
Density | 1.486±0.06 g/cm3(Predicted) |
Boling Point | 344.5±37.0 °C(Predicted) |
Appearance | Crystalline Powder |
Color | White to yellow |
pKa | 0.82±0.30(Predicted) |
Storage Condition | under inert gas (nitrogen or Argon) at 2-8°C |
Refractive Index | 1.671 |
use | 5, 7-dichloro-1, 6-naphthyridine is used as organic synthesis, which can be used in laboratory research and development process and chemical and pharmaceutical synthesis process. |
preparation | step 1: synthesis of 2-(2-ethoxy-2-oxoethyl) nicotinic acid under the protection of nitrogen, slowly dropping ethyl acetoacetate (26.0g) into the mixture of potassium tert-butoxide (33.7g) and isopropanol (500ml), after the dripping is completed, continue stirring for another 2 hours. Anhydrous copper acetate (5.5g,0.03mol) and 2-chloronicotinic acid (15.8g) were added to the reaction solution, heated to 80 ℃ and stirred for 4 hours. Cool to room temperature, quench with water (500mL), and then adjust the pH to 4 with 2N dilute hydrochloric acid. Ethyl acetate (500mL) was added, stirred for 20 minutes and then filtered, the filtrate was separated, the organic phase was concentrated under reduced pressure, toluene (300mL) was added to the residue, stirred for 1 hour, and 2-(2-ethoxy-2-oxoethyl) nicotinic acid (15.5g) was obtained after filtration. Step 2: Synthesis of 1, 6-naphthyridine -5,7(6H,8H)-dione At 0°C, triethylamine (7.5g) and ethyl chloroformate (9.6g) are added to the tetrahydrofuran (200mL) solution of 2-(2-ethoxy-2-oxoethyl) nicotinic acid (15.5g), and the reaction solution is raised to room temperature and stirred for 1 hour. Slowly add ammonia (5mL) and continue stirring for 1 hour. Add water (100mL) and adjust the pH to 7 with dilute hydrochloric acid. After filtration, 1, 6-naphthyridine -5,7(6H,8H)-dione (6.5g) was obtained. Step 3: Synthesis of 5,7-Dichloro-1, 6-naphthyridine Dissolve 1,6-naphthyridine -5,7(6H,8H)-diketone (6.5g) in phosphorus oxychloride (150mL), cool to 0 ℃, add N,N-diisopropylethylamine (10.4g), then heat to 100 ℃ and stir for 16 hours. Cool to room temperature, evaporate to remove phosphorus oxychloride under reduced pressure, add cold water (100mL), filter, and dry the solid in vacuum to obtain 5, 7-dichloro-1, 6-naphthyridine (4.0g). |