Triethylamine → 1-[6-Chloro-1-(2-methoxy-ethoxymethyl)-5-(2-morpholin-4-yl-ethylamino)-1H-benzoimidazol-2-yl]-1H-pyrazole-4-carboxylic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

To a slurry of 4 Å molecular sieves (0.9 g), 1-[5-amino-6-chloro-1-(2-methoxy-ethoxymethyl)-1H-benzoimidazol-2-yl]-1H-pyrazole-4-carboxylic acid ethyl ester (Intermediate from Example 41, product from Step A) (0.187 g, 0.475 mmol), sodium 1-hydroxy-2-morpholin-4-yl-ethanesulfonate (0.122 g, 0.523 mmol) and THF (2.5 mL) was added triethylamine (0.300 mL, 2.15 mmol). The slurry was stirred at 23° C. for 24 h, and sodium triacetoxyborohydride (0.282 g, 1.33 mmol) was added. The reaction mixture was stirred for an additional 24 h. Additional sodium 1-hydroxy-2-morpholin-4-yl-ethanesulfonate (62.0 mg, 0.270 mmol) was added and the reaction was allowed to continue for another 24 h at 23° C. The reaction mixture was diluted with EtOAc, filtered, and washed with saturated aqueous NaHCO3. The aqueous layer was further extracted with EtOAc (2×30 mL). The combined organic layers were washed with brine, dried, filtered, and concentrated under reduced pressure. The residue was purified (FCC) (EtOAc/hexanes) to yield the titled compound (30 mg, 12% crude yield). This compound was used without further purification in subsequent reactions. MS (ESI/CI): mass calcd. for C23H31ClN6O5, 506.2; m/z found, 507.2 [M+H]+.

Provenance & Evidence