HCID 20610247, compound → HCID 20610318, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 2-allyloxycarbonylamino-2-[3-(1-tert-butoxycarbonyl-pyrrolidin-2-yl)-isoxazol-5-ylmethyl]-malonic acid monoethyl ester and 2-allyloxycarbonylamino-2-[3-(1-tert-butoxycarbonyl-pyrrolidin-2-yl)-isoxazol-5-ylmethyl]-malonic acid diethyl ester (10.4 g, 21.5 mmol) was dissolved in dioxane (130 mL) and heated in an oil bath to 125° C. for 3 hours. The dioxane was then removed in vacuo. The residue was dissolved in ethyl acetate, washed with saturated sodium carbonate and brine, dried over magnesium sulfate and concentrated. The crude material was chromatographed on a Biotage Flash 40M column eluting with ethyl acetate/hexanes (1:4) to give the title compound as a clear oil (5.12 g, 56% 2 steps). MS (CI) m/z 338.0 (M-99). 2-Allyloxycarbonylamino-2-[3-(1-tert-butoxycarbonyl-pyrrolidin-2-yl)-isoxazol-5-ylmethyl]-malonic acid diethyl ester was recovered (2.96 g, 27%). MS (CI) m/z 509.9 (M+1), 409.9 (M−99)

Provenance & Evidence