Water → HCID 67066988, compound

To a solution of 2,3-dimethylpyrazine (1.33 g, 12.3 mmol) in tetrachloromethane (30 mL) was added N-bromosuccinimide (6.6 g, 37 mmol)) and 2,2′-azobis(2-methylpropionitrile) (0.2 g, 1.2 mmol). After refluxing under nitrogen for 16 h, the mixture was filtered, and washed with tetrachloromethane. The filtrate was concentrated, and the residue was purified on Biotage silica gel cartridge (gradient 2-20% ethyl acetate in hexanes) to yield 2,3-di(bromomethyl)pyrazine. A solution of 2,3-di(bromomethyl)pyrazine (2.0 g, 7.7 mmol) in N,N-dimethylformamide (100 mL) at 0° C. was mixed with a solution of tritylamine (6.0 g, 23.0 mmol) in N,N-dimethylformamide. The resulting mixture was stirred at room temperature for one h, heated at 60° C. for 3 h, and then poured into water and extracted with ethyl acetate (2×200 mL). The organic layers were washed with water, brine, dried over sodium sulfate and concentrated. The residue was purified on Biotage silica gel cartridge (gradient 2-50% ethyl acetate in hexanes) to yield the N-trityl-pyrrolopyrazine. A portion of this product (420 mg, 1.2 mmol) was treated with 4N of hydrochloric acid in methanol for 2 h. After solvent was removed, the residue was purified on Biotage silica gel cartridge (gradient 0-12% methanol containing 1% ammonium hydroxide in dichloromethane) to yield Intermediate 17.

1. temperatureheated at 60° C. for 3 h
2. extractionextracted with ethyl acetate (2×200 mL)
3. washThe organic layers were washed with water, brine
4. dry with materialdried over sodium sulfate
5. concentrationconcentrated
6. customThe residue was purified on Biotage silica gel cartridge (gradient 2-50% ethyl acetate in hexanes)

ORD record

ord-ca1321760178464ca2336d9959f0f5b6

Source dataset

uspto-grants-2011_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07910596B2