3,5-Dibromo-6-methyl-2-pyrazinamine

To a solution of 6-methylpyrazin-2-amine (14.40 g, 132 mmol) and pyridine (26.0 g, 330 mmol) in DCM (300 mL) was added dropwise slowly bromine (53.00 g, 330 mmol). Afterthe addition, the mixture was stirred at rt overnight. Water (150 mL) was added to quench thereaction, and the resulting mixture was partitioned. The organic phase was washed with saturatedbrine (100 mL), dried over anhydrous sodium sulfate, filtered, and the filtrate was concentratedin vacuo to give the title compound as a yellow solid (34.01 g, 96percent ).MS (ESI, pos. ion) m/z: 267.9 [M+Ht.B. 3, 5-Dibromo-6-methylpyrazine-2-ylamine. 6-Methylpyrazine-2- ylamine (1.18 g, 10.82 mmol) and pyridine (1.79 g, 22.72 mmol) were combined in chloroform (100 mL) at ambient temperature. Bromine (3.63 g, 22.72 mmol) in chloroform (5 mL) was then added drop-wise over 5 minutes. Upon consumption of the starting material, as indicated by TLC, the reaction solution was transferred to a sepratory funnel and the organic layer washed twice with water. The organics were dried over magnesium sulfate, filtered and solvent removed under reduced pressure to afford the title compound (2.70 g, 95 percent yield). MS (ESI) m/z 268.0[M+2]At room temperature, Bromine (5.89 g, 36.54 mmol, 1.90 mL)Of chloroform (15 mL)The solution was slowly added dropwise over 5 minutes6-methylpyrazin-2-amine (2.00 g, 18.33 mmol)In chloroform (170 mL).After completion of the dropwise addition, the reaction was stirred at room temperature for 4.5 h.The reaction was quenched with water (100 mL). The organic layer was washed with water (100 mL), dried over anhydrous magnesium sulfate and the organic layer was concentrated under reduced pressure.Column separation (petroleum ether / ethyl acetate (v / v) = 2/1)To give 4.20 g of a yellowish yellow solid in 86.0percent yield.Following a literature procedure (WO 2007/035154, p 29), bromine (12 mL, 231.0 mmol) was added portion-wise over 5 minutes into a cooled solution of 6-methylpyrazin-2-amine (9.72 g, 89.0 mmol) and lutidine (31.0 mL, 266.0 mmol) in dry acetonitrile at 10° C. The reaction was maintained overnight, allowing the cooling bath to expire. The reaction was queched with aqueous 2.0 M sodium sulfite solution and the pH was adjusted to 8 with the addition of 6 M NaOH. The mixture was concentrated in vacuo and the remaining aqueous portion was cooled to 5° C. overnight. The resulting brown solid was isolated by filtration and triturated with a 9:1 EtOAc-hexanes solution to furnish 11.9 g of 3, 5-dibromo-6-methylpyrazin-2-amine. The collected filtrate was concentrated and the resulting solid triturated again to provide an additional 2.2 g of product: LCMS (m/z): 267.9 (MH[0280] 3, 5-Dibromo-6-methylpyrazin-2-amine VII: To a solution of 6- methylpyrazin-2-amine VI (2.00 g, 18.3 mmol) in THF (40 mL) at 10 °C, was added N- bromosuccinimide (6.70 g, 37.6 mmol) portion wise over 15 min and the mixture allowed to warm to room temperature while stirring. After 2 h, the reaction was concentrated under reduced pressure and the resulting residue was purified by column chromatography (silica, gradient, hexanes to EtOAc) to provide 3, 5-dibromo-6- methylpyrazin-2-amine VII (3.10 g, 64percent) as an orange solid: NMR (400 MHz, CDCI

Molecular Weight:266.92
XLogP3:1.9
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:3
Exact Mass:266.88297
Monoisotopic Mass:264.88502
Topological Polar Surface Area:51.8
Heavy Atom Count:10
Complexity:122
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes