Sodium borohydride → 5-{4-[(3-Ethylpentylamino)methyl]phenoxy}thiophene-2-carboxamide

Participants

Reaction Steps

Place 5-(4-formylphenoxy)thiophene-2-carboxamide (Example 10, Part C) (0.235 g, 0.948 mmol), 3-ethylpentylamine (Part B) (0.115 g, 0.996 mmol) and 3 Å molecular sieves in a vial. Add methanol (4.7 mL), cap and stir overnight. Add NaBH4 (0.0359 g, 0.948 mmol) and stir until the gasses stop evolving. Load the reaction mixture directly onto a 25 g ISCO® pre-load column. Dry the column in a vacuum oven at room temperature. Purify by eluting through a 40 g ISCO® column with 5% to 20% (2.0 M NH3 in methanol) in ethyl acetate over 45 minutes to give the title compound: TOF MS ES+ 347.2 (M+H)+, HRMS calcd for C19H27N2O2S 347.1793 (M+H)+, found 347.1799, time 0.38 min; HPLC [YMC-Pro pack C-18 (150×4.6 mm, S-5 microm), 0.05% TFA/acetonitrile in 0.05% TFA/water at 1.0 mL/min, 10-20% over 5 min, 20-95% over 18], tR=12.4 min, 100% purity.

Provenance & Evidence