Sulfamic Acid → HCID 90040678, compound

Participants

Reaction Steps

To a stirred mixture of 2-bromo-3-methyl-5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazine-7-carbaldehyde (3.17 g, 8.55 mmol), tert-butanol (10 mL), tetrahydrofuran (10 mL), and water (10 mL) was added sulfamic acid (3.32 g, 34 mmol) and then a solution of potassium dihydrogen phosphate (8.85 g, 65 mmol) and sodium chlorite (1.93 g, 21 mmol) in water (42 mL). After 1 h the mixture was diluted with ethyl acetate, washed once with brine, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure to give 2-bromo-3-methyl-5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxylic acid (3.02 g, 91%) as a light yellow solid. This material was used in the next step without further purification. 1H NMR (400 MHz, DMSO-d6) δ ppm −0.10 (s, 9H), 0.83 (t, J=8.0 Hz, 2H), 2.69 (s, 3H), 3.55 (t, J=8.0 Hz, 2H), 5.64 (s, 2H), 8.64 (s, 1H), 12.46 (br s, J=9.06 Hz, 1H, —COOH).

Provenance & Evidence