Diisopropylethylamine → 5-(2-Methylprop-1-en-1-yl)pyrazin-2-amine

Temperature

130 °C

A mixture of the crude isobutenyltri-n-butyltin (6.90 g, 58 purity), 2-amino-5-bromopyrazine (1.92 g, 11 mmol), and N,N-diisopropylethylamine (5 mL) in N,N-dimethylformamide (50 mL) was treated with lithium chloride (2.0 g) and tetrakis(triphenylphosphine)palladium(0) (381 mg, 0.33 mmol). The mixture was stirred at 130° C. for 4 h, at which time, thin layer chromatography indicated complete consumption of the starting material. The mixture was concentrated in vacuo. The residue was treated with a saturated aqueous potassium fluoride solution and then extracted with ethyl acetate. The organic layer was washed with a saturated aqueous sodium chloride solution, dried over sodium sulfate, filtered, and concentrated in vacuo. Flash chromatography (Merck Silica gel 60, 230–400 mesh, 1.5/1 hexanes/ethyl acetate) afforded 2-amino-5-(2,2-dimethylvinyl)-pyrazine (420 mg, 26%).

1. customconsumption of the starting material
2. concentrationThe mixture was concentrated in vacuo
3. additionThe residue was treated with a saturated aqueous potassium fluoride solution
4. extractionextracted with ethyl acetate
5. washThe organic layer was washed with a saturated aqueous sodium chloride solution
6. dry with materialdried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated in vacuo

ORD record

ord-82edf9a5ea144812907b8b8bcc1b70a6

Source dataset

uspto-grants-2006_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07132425B2