2,6-Lutidine → HCID 57799150, Verbindung

Oxalyl chloride (0.17 ml, 1.9 mmol) was added to a slurry of 2-(2-trimethylsilanylmethoxy-ethyl)-2H-pyrazole-3-carboxylic acid) (Heterocycles (1992) 34 303-314), (428 mg, 1.76 mmol) in dichloromethane (15 ml), 1 drop of dimethylformamide was added and the reaction stirred at room temperature under N2 for 1 hour before concentrating in vacuo and azeotroping with dichloromethane. The resulting acid chloride was dissolved in 5 ml acetonitrile and added to a solution of 3-(2,5-dichloro-phenyl)pyrazine-2,6-diamine (Preparation 11, 300 mg, 1.18 mmol) in acetonitrile (15 ml) and 2,6-lutidine (0.21 ml, 1.8 mmol). The reaction was stirred at room temperature under N2 for 72 hours before concentrating in vacuo then partitioning between 50 ml ethyl acetate and 50 ml water. The organic layer was dried over MgSO4 and concentrated in vacuo to give a brown oil which was purified by column chromatography (ethyl acetate, heptane, 1:2) to give 52 mg of the title product.

1. concentrationbefore concentrating in vacuo
2. customazeotroping with dichloromethane
3. dissolutionThe resulting acid chloride was dissolved in 5 ml acetonitrile
4. stirringThe reaction was stirred at room temperature under N2 for 72 hours
5. concentrationbefore concentrating in vacuo
6. customthen partitioning between 50 ml ethyl acetate and 50 ml water
7. dry with materialThe organic layer was dried over MgSO4
8. concentrationconcentrated in vacuo
9. customto give a brown oil which
10. customwas purified by column chromatography (ethyl acetate, heptane, 1:2)

ORD-Eintrag

ord-33a657c2ac13400dadb592821632972f

Quelldatensatz

uspto-grants-2009_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07572797B2