0.16 ml of 1,2-dibromoethane is added at ambient temperature, under argon, to a suspension of 1.35 g of powdered zinc in 10 ml of tetrahydrofuran. The mixture is heated for 5 minutes at 65° C., then brought to ambient temperature, and 0.23 ml of trimethylsilyl is then added. After stirring the mixture for 30 minutes, a solution of 4.5 g of the compound obtained in Step 2 in 8 ml of tetrahydrofuran is slowly added, and then after 45 minutes a solution, prepared ex situ 10 minutes beforehand, of 0.2 g of Pd2(dba)3 and 0.2 g of P(2-furyl)3 in 5 ml of tetrahydrofuran is added by cannulation under argon and, finally, 5.5 g of 1-benzyl-4-bromo-1H-pyrrolo[3,2-c]pyridine in 30 ml of a 1/1 tetrahydrofuran/dimethylamine mixture are added. The reaction mixture is heated at 65° C. for 16 hours and then, after return to ambient temperature, filtered and concentrated in vacuo. Chromatography on silica gel (cyclohexane/ethyl acetate: 50150) enables the expected product to be isolated.
