Potassium Carbonate → 2-chloro-4,4-difluoro-1'-[[1-[3-(methoxymethyl)-2-pyridyl]-3-methyl-pyrazol-4-yl]methyl]spiro[5H-thieno[2,3-c]pyran-7,4'-piperidine]

Participants

Reaction Steps

To a screw-cap test tube is added copper (I) iodide (1.15 g, 6.02 mmol), 2-chloro-4,4-difluoro-1′-[(3-methyl-1H-pyrazol-4-yl)methyl]spiro[5H-thieno[2,3-c]pyran-7,4′-piperidine] (15 g, 40.12 mmol), potassium carbonate (11.76 g, 84.26 mmol), 15 mL of toluene (previously bubbled with nitrogen for 20 minutes) and a stir bar. The reaction mixture is bubbled with nitrogen for additional 10 min and then 2-bromo-3-methoxymethyl-pyridine (10.54 g, 52.16 mmol), and trans-N,N′-dimethylcyclohexane-1,2-diamine (1.90 mL, 12.04 mmol) are added. The reaction tube is quickly sealed (caution: build-up of pressure possible; use a safety shield), stirred at room temperature for 5 min and immersed in a preheated oil bath at 115° C. for 24 h. The sample is cooled down to room temperature, diluted with ethyl acetate and filtered through celite. The solvent is evaporated in vacuo. The residue is purified by normal phase Isco chromatography using hexane/ethyl acetate (30-70%). The desired fractions are collected and evaporated. Some impure fractions (<2 g) are repurified by normal phase Isco chromatography using hexane/ethyl acetate (20-60% in ethyl acetate) as eluent. All the fractions containing final compound are combined and evaporated to dryness in vacuo. The residue is dissolved in dichloromethane and washed with 10% aqueous solution of ammonium hydroxide to remove copper residues. The organic solvent is evaporated and the compound is dried overnight to yield 13 g of 2-chloro-4,4-difluoro-1′-[[1-[3-(methoxymethyl)-2-pyridyl]-3-methyl-pyrazol-4-yl]methyl]spiro[5H-thieno[2,3-c]pyran-7,4′-piperidine]. MS (m/z): 495 (M+1).

Provenance & Evidence