1: N,N-dimethyl-2,4-dimethylbenzamide With lithium diisopropyl amide in tetrahydrofuran; hexane T=-78°C; Metallation; 1 h; 2: para-chloro-benzonitrile in tetrahydrofuran; hexane T=-78 - 20°C; Cyclization; 3 h;

1.1: 10.03 g / H2O / 1 h / -5 - 20 °C 2.1: LDA / tetrahydrofuran; hexane / 1 h / -78 °C 2.2: 47 percent / tetrahydrofuran; hexane / 3 h / -78 - 20 °C View Scheme

1.1: phosphorus pentachloride / 160 °C 2.1: 10.03 g / H2O / 1 h / -5 - 20 °C 3.1: LDA / tetrahydrofuran; hexane / 1 h / -78 °C 3.2: 47 percent / tetrahydrofuran; hexane / 3 h / -78 - 20 °C View Scheme