Sodium triacetoxyborohydride → (+/-)-(3-{[1-(3-benzyl-4-oxo-3,4-dihydro-pyrrolo[2,1-f][1,2,4]triazin-2-yl)-propyl]-cyclohexyl-amino}-propyl)-carbamic acid 9H-fluoren-9-ylmethyl ester

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Reaction Steps

A mixture of 3-benzyl-2-(1-cyclohexylamino-propyl)-3H-pyrrolo[2,1-f][1,2,4]triazin-4-one (Example 28, 150 mg, 0.41 mmol), (3-oxo-propyl)-carbamic acid 9H-fluoren-9-ylmethyl ester (Org. Lett. 2002, 4, 3001–3003, 184 mg, 0.62 mmol), acetic acetic (1.5 eq), 4 Å molecular sieves (100 mg), and 1,2-dichloroethane (10 mL) was stirred at room temperature for 30 min, then treated with sodium triacetoxyborohydride (130 mg, 0.62 mmol). After 3 h, the mixture was filtered and the filtrate washed with saturated sodium bicarbonate and water, dried (MgSO4), and concentrated. The residue was purified by flash column chromatography on silica gel eluting with ethyl acetate/hexanes to give the title compound as a white solid (115 mg, 44%): MS (ESI+) 644.44 (M++H).

Provenance & Evidence