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

HRID 246371Notes

Reaction equation

HRID 246371 reaction equation
I[C:2]1[C:3]2[CH2:10][CH2:9][CH2:8][C:4]=2[N:5]([CH3:7])[N:6]=1.C([Mg]Cl)(C)C.[CH2:16]([Sn:20]([CH2:26][CH2:27][CH2:28][CH3:29])([CH2:22][CH2:23][CH2:24][CH3:25])Cl)[CH2:17][CH2:18][CH3:19]>C1COCC1>[CH3:7][N:5]1[C:4]2[CH2:8][CH2:9][CH2:10][C:3]=2[C:2]([Sn:20]([CH2:22][CH2:23][CH2:24][CH3:25])([CH2:26][CH2:27][CH2:28][CH3:29])[CH2:16][CH2:17][CH2:18][CH3:19])=[N:6]1

Participants

5

Conditions

Temperature
-16 °C

Procedure

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.

Workup

  1. temperatureThe reaction mixture was warmed to 25° C.
  2. stirringstirred for 1.5 h
  3. customThe reaction mixture was quenched with saturated ammonium chloride solution
  4. extractionextracted with EtOAc (3×30 mL)
  5. washthe combined organics were washed with water (20 mL), brine (2×20 mL)
  6. dry with materialdried over MgSO4
  7. concentrationconcentrated
  8. customThe residue was dried under high vacuum

Sources & evidence

ORD record
ord-676561e4216c4ea0974fc14e3d9fdb35
Source dataset
uspto-grants-2014_02
Patent number
US08658646B2

Reaction notes

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