1.1: 4-(N,N-dimethlyamino)pyridine; 2,4,6-trichlorobenzoyl chloride; triethylamine / toluene / 48 h / 23 °C / Inert atmosphere 2.1: sodium tetrahydroborate / methanol / 30 h / 0 °C / Inert atmosphere 3.1: n-butyllithium; 1,1,1,3,3,3-hexamethyl-disilazane / tetrahydrofuran / -10 - 0 °C / Inert atmosphere 3.2: 12 h / 23 °C / Inert atmosphere 4.1: 18-crown-6 ether / toluene / 36 h / Inert atmosphere; Reflux View Scheme