1: 4-chlorobenzaldehyde With n-butyllithium; di-(2-methoxyethyl)amine in tetrahydrofuran; hexane T=-20°C; 0.75 h; Inert atmosphere; 2: With n-butyllithium in tetrahydrofuran; hexane T=-20 - 0°C; 2.16667 h; Inert atmosphere; 3: N,N-dimethyl-formamide Further stages;

aluminium trichloride T=170 - 200°C;