Ethyl Acetate → tert-Butyl-(1S,3R)-3-(6-tosyl-6H-pyrrolo[2,3-e][1, 2, 4]triazolo[4,3-a]pyrazin-1-yl)cyclopentylcarbamate

Participants

Reaction Conditions

Reaction Steps

To a solution of tert-butyl (1S,3R)-3-(2-(5-tosyl-5H-pyrrolo[2,3-b]pyrazin-2-yl)hydrazinecarbonyl)cyclopentylcarbamate (9.30 g, 18.1 mmol, prepared using A from Example #1 Step D, and (1R,3S)-3-tert-butoxycarbonylamino)cyclopentanecarboxylic acid [Peptech]) in 1,4-dioxane (100 mL) was added TEA (10.0 mL, 72.3 mmol) and SOCl2 (2.11 mL, 28.9 mmol). The mixture was heated at about 80° C. for about 1.5 h. The reaction mixture was cooled to ambient temperature, EtOAc (200 mL) and water (200 mL) were added, and the layers were separated. The aqueous portion was extracted with EtOAc (2×100 mL) and the combined organic extracts were washed with saturated aqueous NaHCO3 (100 mL) and brine (100 mL), dried over anhydrous Na2SO4, filtered, and concd under reduced pressure. The crude material was purified by silica gel chromatography eluting with a gradient of 25-100% EtOAc in DCM to give tert-butyl-(1S,3R)-3-(6-tosyl-6H-pyrrolo[2,3-e][1,2,4]triazolo[4,3-a]pyrazin-1-yl)cyclopentylcarbamate (7.65 g, 85%): LC/MS (Table 1, Method a) Rt=2.37 min; MS m/z: 497 (M+H)+.

Provenance & Evidence