tert-Butyl (5-chloropyrazin-2-yl)carbamate synthesis

Yield:1206249-43-5 90%

Reaction Conditions:

with dmap;triethylamine in 1,4-dioxane at 100; for 1 h;

Steps:

16.1 Step 1. Synthesis of tert-butyl N-(5-chloropyrazin-2-yl)carbamate To

To a mixture of 5-chloro-pyrazinamine (5 g, 38.59 mmol) in dioxane (50 mL) was added Boc₂O (12 g, 54.98 mmol), DMAP (9 g, 73.66 mmol) and TEA (3.51 g, 10.78 mmol). The resulting mixture was stirred for 1 h at 100 °C. The reaction mixture was diluted with 500 ml H₂O. The resulting solution was extracted with EtOAc (300 mL x 3) and the organic layers were combined. The organic layer was dried over anhydrous sodium sulfate and concentrated under vacuum. The residue was purified by reverse phase flash chromatography eluting with ACN/H₂O (0.05% NH4HCO₃) (80%-100%) to afford tert-butyl N-(5-chloropyrazin-2-yl)carbamate (8 g, 90% yield) as a yellow solid. LCMS (ESI) [M+H]⁺: 230.27.

References:

WO2021/178420,2021,A1 Location in patent:Page/Page column 92