Acetic Acid → [2-(2-Cyclopentyl-4,6-dioxo-tetrahydro-pyran-2-yl)-ethyl]-carbamic Acid Tert-Butyl Ester

Participants

Reaction Steps

To 7-tert-butoxycarbonylamino-5-cyclopentyl-5-hydroxy-3-oxo-heptanoic acid methyl ester (1.36 g, 3.8 mmol) from Step 3 above dissolved in MeOH (50 mL) was added a NaOH solution (2.8 M, 2.7 mL, 7.6 mmol). The reaction was stirred at room temperature for 18 hours. The reaction was then quenched with acetic acid (0.44 mL, 7.7 mmol) and concentrated by rotary evaporation to an oil. The oil was dissolved in CH2Cl2 and washed with water. The organic layer was separated, and dried over Na2SO4. The solids were removed by filtration, and the liquid was concentrated to yield the product (1.061 g, 86% yield). MS (ESI): 324 (M−H).

Provenance & Evidence