Ethyl chloroformate → HCID 58293770, compound

Participants

Reaction Steps

To a solution of 1-(thiophen-2-yl)butan-2-amine (2.1 g, 13.72 mmol) in methylene chloride (40 mL) was added ethyl glyoxylate (2.80 g, 13.72 mmol) at RT. One drop of acetic acid was added, the mixture stirred at RT for 75 min, and sodium triacetoxyborohydride (4.36 g, 20.58 mmol) was added. The reaction was stirred at RT for 15 hours before quenching the reaction by adding 5 mL of acetic acid. The volatiles were removed under reduced pressure and the residue dissolved in 40 mL THF. Saturated sodium bicarbonate (40 mL) was added carefully, followed by the addition of ethyl chloroformate (2.978 g, 2.624 mL, 27.44 mmol). Solid NaHCO3 was subsequently added portionwise until gas evolution ceased. The reaction was stirred at RT overnight and extracted with EtOAc (2×). The organics were dried over Na2SO4, the volatiles removed under reduced pressure, and there resulting yellow oil purified by silica gel chromatography, using a 0-35% EtOAc/hexanes gradient as eluant, to produce ethyl 2-(ethoxycarbonyl-(1-(thiophen-2-yl)butan-2-yl)amino)acetate (Compound 1035, 3.03 g) as a colorless oil.

Provenance & Evidence