Dimethyl Sulfoxide → 3-Iodo-1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazole-4-carbaldehyde

Participants

Reaction Conditions

Reaction Steps

To a solution of oxalyl chloride (33.51 g, 22.8 mL, 263 mmol) in DCM (320 mL) at −65° C. under a dry N2 atm. was added DMSO (27.28 g, 24.8 mL, 350.3 mmol) dropwise. The reaction was stirred at −65° C. for 0.5 h then treated dropwise with a solution of (3-iodo-1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazol-4-yl)methanol (27 g 87.66 mmol) in DCM (75 mL. The mixture was stirred at −65° C. for 1 h then treated with TEA (53.14 g, 73.2 mL, 525 mmol) then warmed to rt and stirred for 0.5 h. DCM (300 mL) was added and the mixture washed with 1N HCl (150 mL×2). The organic layer was dried and then concentrated under vacuum. The residue was purified by SGC using Hex: EA (0%-15%) as eluent to afford 3-iodo-1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazole-4-carbaldehyde (22 g, yield: 82%). LCMS (method C): RT=1.97 min, m/z=307.0 [M+H]+.

Provenance & Evidence