1: 2-(acetoxymethyl)phenol With isopropylmagnesium chloride in tetrahydrofuran T=-78°C; Hetero-Diels-Alder reaction; 0.25 h; 2: ethyl vinyl ether in tetrahydrofuran T=-78 - 25°C; Hetero-Diels-Alder reaction; 16 h;

copper(l) iodide; triphenylphosphine T=110°C; 26 h; Inert atmosphere;

1: 32 percent / PPTS 2: 94 percent / NaOH / ethanol / 1 h / 18 °C 3: 69 percent / pyridinium chlorochromate, NaOAc / CH2Cl2 / 3 h / Ambient temperature View Scheme

T=100°C; 12 h;

T=25°C; 3 h;