potassium tert-butylate in ethylene glycol dimethyl ether; tert-butyl alcohol T=0 - 20°C; 5.16667 h;

1.1: triethylamine; chloroformic acid ethyl ester / dichloromethane / 0.17 h / -20 - -10 °C / |Inert atmosphere 1.2: -20 - -15 °C 2.1: trifluoroacetic anhydride / 0.5 h / 20 °C View Scheme