5-BROMO-6-CHLOROPYRAZIN-2-AMINE

6-chloropyrazine-2-amine (10.4 g, 80 mmol) was dissolved in methanol (300 ml), and N-bromosuccinimide (15.6 g, 88 mmol) was added thereto while stirring at room temperature. After stirring for additional 60 minutes, the reaction product was concentrated under reduced pressure, followed by adding water so that the reaction product was extracted 3 times with ethyl acetate. The organic later was collected, dried over magnesium sulfate, and then concentrated under reduced pressure. Thereafter, the residue was purified on a silica gel column using chromatography. The title compound (12.0 g, 72percent) was obtained by eluting as a mixed solvent (3:1 v/v) of hexane and ethyl acetate. 2, 6-Dichloropyrazine (2.89 g, 19.4 mmol) was stirred in aqueous NHSynthesis 2-1 -B 5-bromo-6-chloropyrazin-2-amine 6-Chloropyrazin-2-amine (2.50 g, 19.3 mmol) was stirred in dichloromethane (60 mL) and cooled to O°C. N-Bromosuccinimide (2.92 g, 16.4 mmol) was added slowly and the reaction mixture was stirred at 0°C for 60 minutes. The reaction mixture was filtered through celite and concentrated to give a brown oil. Purification by flash chromatography, eluting with 0-25percent ethyl acetate-hexane, gave the title compound as a yellow solid (1.69 g, 8.16 mmol, 42percent). Preparation of 3-bromo-6-chloropyrazin-2 -amine (B-10-3).-10-2 B-10-3 B-10-3bTo a solution of compound B-10-2 (110 g, 0.85 mol) in CHCINaH (60 % in mineral oil) (1.84g, 76.73 mmol, 2.0 eq) was added slowly to ethylene glycol (50 mL) at 0C over a period of 15 minutes under inert atmosphere and reaction mixture was allowed to stir at the same temperature for 30 minutes. To this mixture was added Then 5- bromo-6-chloropyrazin-2-amine (8 g, 38.36 mmol, 1 eq) at 0C and the resulting mixture was allowed to stir 140C for 1 h. Progress of reaction was monitored by TLC. After completion, reaction mixture was diluted with ice cold water (500 mL) and extract with ethyl acetate (2 x 500 mL). Combined organic layer was washed with brine and dried over anhydrous sodium sulfate. Removal of solvent under reduce pressure afforded 2-(6-amino-3-bromopyrazin-2-yloxy)ethanol (8.97g, 99.66 %) as white solid which was used in the next step without purification.In a pressure tube were mixed To a solution of To a solution of Copper iodine (190 mg, 1 mmol), triethylamine (16.7 ml, 120 mmol), and [1, 1'-bis(diphenylphosphino)ferrocene]dichloropalladium(II) complex with dichloromethane (1.3 g, 1.6 mmol), and tetrahydrofuran (100 ml) were added to Example 6 2-Amino-5, 7-dihydrofuro[3, 4-b]pyrazine A mixture of A reaction vessel containing a mixture of Step 1: 4-(5-amino-3-chloropyrazin-2-yl)benzonitrile A mixture of Sodium nitrite (3.6 g, 53 mmol) was added to a solution of General procedure: To the DMF (1ml) was added dropwise phenyl chloroformate (2equiv). The mixture was stirred for 5min at room temperature. Then 6-chloro-2-aminopyrazine (1mmol) was introduced to the mixture. After 5min, the solvent (isopropyl alcohol:diethyl ether, v/v=1:2) was poured into the mixture. The precipitated product 6a was filtered off, washed with the solvent and dried.

Molecular Weight:208.44
XLogP3:1.4
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:3
Exact Mass:206.91989
Monoisotopic Mass:206.91989
Topological Polar Surface Area:51.8
Heavy Atom Count:9
Complexity:102
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes