Iodoethane → HCID 58382052, compound

Participants

Reaction Conditions

Reaction Steps

The 4-chloro-3-iodo-1-(triisopropylsilyl)-1H-pyrrolo[2,3-b]pyridine (27.0 g, 62.1 mmol) in THF (300 mL) was cooled to about −75° C. then t-BuLi (1.7 M in pentane, 73.1 mL, 124 mmol) was added over about 30 min keeping the internal temperature below about −70° C. After complete addition, EtI (15.0 mL, 186 mmol) was added. The mixture was warmed slowly to about −40° C. then the mixture was allowed to warm to rt. Saturated aqueous NaHCO3 (50 mL) was added and the mixture was stirred for about 30 min. The mixture was filtered and the solids washed with EtOAc (3×50 mL). The solvents were removed under reduced pressure then the material was partitioned between EtOAc (200 mL) and water (50 mL). The layers were separated then the organic layer was washed with saturated aqueous NaCl (50 mL), dried over anhydrous MgSO4, filtered and concentrated under reduced pressure. The resulting material was treated with MeOH (80 mL) then warmed to about 60° C. The mixture was cooled to rt and the resulting slurry stirred overnight at rt. The solids were collected by filtration then washed with MeOH (10 mL). The filtrate was concentrated under reduced pressure then purified by silica gel chromatography using a 120 g silica gel column and eluting with heptane. The material was stirred with MeOH (15 mL) overnight then the solid was collected by filtration and washed with MeOH (2 mL). The solid material was combined with the first crop of solids and dried under reduced pressure to give 4-chloro-3-ethyl-1-(triisopropylsilyl)-1H-pyrrolo[2,3-b]pyridine (17.4 g, 83%): LC/MS (Table 2, Method g) Rt=3.21 min; MS m/z 337 (M+H)+.

Provenance & Evidence