N,N,N',N'-Tetramethylethylenediamine → 1-Benzenesulfonyl-4-chloro-1H-pyrrolo[3,2-c]pyridine-2-carboxylic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

Lithium diisopropylamide (3.2 mL of a 1.5 M solution in THF, 4.80 mmol) is added to a solution of tetramethylethylenediamine (0.71 mL, 4.75 mmol) and 1-benzenesulfonyl-4-chloro-1H -pyrrolo[3,2-c]pyridine (1 g, 3.42 mmol) in THF (13 mL). The resulting yellow solution is stirred at −78° C. for 1 hour, and then ethyl chloroformate (0.78 mL, 8.16 mmol) is added dropwise. The mixture is slowly brought to room temperature over a 3.5 hour period. The reaction is quenched with saturated NH4Cl solution and then diluted with ethyl acetate. The organic layer is washed with brine, dried over MgSO4, filtered and concentrated to give a light brown solid (1.46 g) as the product which is used in the subsequent step without further purification.

Provenance & Evidence