Tributyltin Chloride → 1-Methyl-3-(tributylstannyl)-1,4,5,6-tetrahydrocyclopenta[c]pyrazole

Participants

Reaction Conditions

Reaction Steps

3-Iodo-1-methyl-1,4,5,6-tetrahydrocyclopenta[c]pyrazole (177 mg, 714 μmol) was dissolved in THF (3 mL). The colorless solution was cooled to −16° C. (NaCl/ice bath). isopropylmagnesium chloride 2 M in THF (400 μL, 799 μmol) was added dropwise at −16° C. The reaction mixture was stirred at −16° C. for 20 min. Then, tributylchlorostannane (267 mg, 223 μL, 821 μmol) 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 and then extracted with EtOAc (3×30 mL), the combined organics were washed with water (20 mL), brine (2×20 mL), dried over MgSO4 and concentrated. The residue was dried under high vacuum yielding 1-methyl-3-(tributylstannyl)-1,4,5,6-tetrahydrocyclopenta[c]pyrazole which was taken into the next step without further treatment.

Provenance & Evidence