1: 1-methyl-benzimidazole With n-butyllithium in tetrahydrofuran; hexane T=-30°C; 0.5 h; Inert atmosphere; 2: chloro-diphenylphosphine in tetrahydrofuran; hexane T=-30 - 50°C; Inert atmosphere;

T=90 - 95°C; 1.5 h;