N,N,N',N'-Tetramethylethylenediamine → [2-(2-Dimethylamino-ethyl)-benzo[b]thiophen-3-yl]-pyridin-2-yl-methanol

Participants

Reaction Conditions

Reaction Steps

To a cooled (−78° C.) solution of [2-(3-bromo-benzo[b]thiophen-2-yl)-ethyl]-dimethyl-amine (800 mg, 2.8 mmol) in anhydrous toluene (30 mL), TMEDA (420 uL, 2.8 mmol) was added followed by nBuLi (2.1 mL, 2.6 mmol, 1.6M in hexanes). The mixture was stirred for 40 min at −78° C. and pyridine-2-carbaldehyde (800 uL, 8.4 mmol) was added. The mixture was stirred for 6 hrs during which the temperature reached 0° C., quenched with sat NH4Cl/NaHCO3 and extracted with EtOAc (3×). The combined organic layers were dried (Na2SO4), concentrated and purified by silical gel column chromatography (gradient of DCM/MeOH=98/2 up to 94/6) to afford [2-(2-dimethylamino-ethyl)-benzo[b]thiophen-3-yl]-pyridin-2-yl-methanol (Compound 13-1) (721 mg) in 82% yield. MH+=313.0, tR=2.49 min (Method 2).

Provenance & Evidence