Tributyltin Chloride → 5-methoxy-1-methyl-3-(tributylstannyl)-1H-indazole

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

3-iodo-5-methoxy-1-methyl-1H-indazole (0.355 g, 1.23 mmol) was dissolved in THF (3.00 mL). The yellow solution was cooled to −16° C. (NaCl/ice bath), isopropylmagnesium chloride 2M in THF (690 μL, 1.38 mmol.12) was added dropwise at −16° C. The reaction mixture was stirred at −16° C. for 20 min where a solid precipitated. Then, tributylchlorostannane (461 mg, 384 μL, 1.42 mmol.15) was added slowly. The reaction mixture was warmed to 25° C. and stirred for 1.5 h. The reaction mixture was quenched with saturated ammonium chloride solution, extracted with dichloromethane (3×30 mL), organics dried over MgSO4 and concentrated to a yellow oil. The residue was dried under high vacuum to give crude 5-methoxy-1-methyl-3-(tributylstannyl)-1H-indazole, which was used directly in the next step without further purification. The crude mass exceeded the expected amount so the yield was assumed to be quantitative.

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