1: methanephosphonic acid dimethyl ester With n-butyllithium in hexane; toluene T=-78°C; 1 h; Inert atmosphere; 2: N-methoxy-N-methyl-2-(4-methylphenyl)acetamide in hexane; toluene T=-78°C; 2 h; Inert atmosphere;

1.1: 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; triethylamine / acetonitrile / 1 h / 20 °C / Inert atmosphere 2.1: n-butyllithium / hexane; toluene / 1 h / -78 °C / Inert atmosphere 2.2: 2 h / -78 °C / Inert atmosphere View Scheme