triethylamine in dichloromethane T=20°C; 15 h; Inert atmosphere;

1: prop-2-ynyl-carbamic acid tert-butyl ester With sodium hydride in N,N-dimethyl-formamide; mineral oil T=0 - 20°C; Inert atmosphere; 2: methyl iodide in N,N-dimethyl-formamide; mineral oil T=0 - 20°C;

1.1: dichloromethane / 0 - 20 °C 2.1: potassium hydride / tetrahydrofuran / 1 h / 0 °C / Inert atmosphere 2.2: 0 - 20 °C / Inert atmosphere View Scheme