5-CHLORO-1-TRIISOPROPYLSILANYL-1H-PYRROLO[2,3-B]PYRIDINE synthesis

Yield:-

Reaction Conditions:

Stage #1: 5-bromo-1-(triisopropylsilyl)-1H-pyrrolo[2,3-b]pyridinewith n-butyllithium in tetrahydrofuran;hexane at -78; for 1 h;
Stage #2: with hexachloroethane in tetrahydrofuran;hexane; for 3 h;

Steps:

5.1

Step 1-Preparation 5-chloro-1-triisopropylsilanyl-1H-pyrrolo[2,3-b]pyridine (5)To 5-bromo-1-triisopropylsilyl-7-azaindole (2, 1.60 g, 4.53 mmol, prepared as described in Example 4) in tetrahydrofuran (50.0 mL), under an atmosphere of nitrogen at -78° C., was added tert-butyllithium (1.70 M in hexane, 6.12 mL). The reaction was stirred for 1 hour, followed by addition of hexachloroethane (1.29 g, 5.43 mmol). The reaction was stirred for 3 hours, poured into water, and extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated to give the crude compound (5, 1.60 g). MS (ESI)[M+H⁺]⁺=309.3.

References:

US2008/167338,2008,A1 Location in patent:Page/Page column 35