Methyl iodide → 3-iodo-1,6,6-trimethyl-4,5,6,7-tetrahydro-1H-indazole

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-iodo-6,6-dimethyl-4,5,6,7-tetrahydro-1H-indazole (919 mg, 3.33 mmol) in THF (8 mL) at 0° C. was added KOt-Bu (523 mg, 4.66 mmol). The reaction mixture was stirred at 0° C. for 30 min then iodomethane (0.29 mL, 4.66 mmol) was added. The reaction mixture was stirred at 0° C. for 30 min then warmed to room temperature and stirred for 1.5 h. The reaction was quenched with water and extracted with EtOAc (2×). The combined organics were dried over MgSO4 and concentrated. The residue was absorbed onto SiO2 and purified by chromatography with 10% to 20% EtOAc/hexanes to afford 523 mg (54%) of 3-iodo-1,6,6-trimethyl-4,5,6,7-tetrahydro-1H-indazole as a colorless oil. 1H NMR (CDCl3, 300 MHz): δ (ppm) 3.72 (s, 3H), 2.33 (t, J=6.4 Hz, 2H), 2.29 (s, 2H), 1.51 (t, J=6.4 Hz, 2H), 1.02 (s, 6H). Also isolated 160 mg (17%) of 3-iodo-2,6,6-trimethyl-4,5,6,7-tetrahydro-2H-indazole as a white solid. 1H NMR (CDCl3, 300 MHz): δ (ppm) 3.87 (s, 3H), 2.41 (s, 2H), 2.36 (t, J=6.6 Hz, 2H), 1.54 (t, J=6.6 Hz, 2H), 1.00 (s, 6H).

Provenance & Evidence