Triethyl borate → HCID 57936314, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 1-Methyl-indole (1.00 g, 3.81 mmol) in 30 ml of THF was added 1-bromo-pyrrolidine-2,5-dione (1.36 g, 3.81 mmol) and the mixture was stirred for 2 hours. The reaction mixture was poured into 200 ml of hexanes and purified by filtration over a short plug of silicagel (Ether/hexanes:1/1). The solution was concentrated close to dryness, redissolved in 25 ml of THF and cooled to −78° C. Tert.-butyllithium (5.08 ml of a 1.5M solution in pentane, 7.62 mmol) was added dropwise and stirred for 15 minutes. Then, triethylborate (0.65 ml, 3.81 mmol) was added in one portion and stirring was continued for 2 hours. The reaction was quenched with 3.5 ml of MeOH and 10 ml of water. The mixture was given into EtOAc and the aqueous layer was extracted with EtOAc. The combined organic phases were dried over sodium sulfate and evaporated to give a green suspension, which was used without further purification. The title compound was prepared analogous to Step C of Method C, starting from this crude boronic acid and (4-chloro-pyrimidin-2-yl)-(2,2,6,6-tetramethyl-piperidin-4-yl)-amine using bis(triphenylphosphine)palladium(II) dichloride as a catalyst. Yield: 327 mg (48%).

Provenance & Evidence