Triethylamine → {2-[5-Dimethylamino-3-methyl-1-(2,4,6-trichlorophenyl)-1H-pyrazol-4-yl-methyl]-1,2,3,4-tetrahydro-isoquinolin-3-yl}-methanol

Participants

Reaction Conditions

Reaction Steps

To an ice-bath-chilled, well-stirred solution of the compound of Step C (160 mg, 0.48 mmol and triethylamine (0.08 ml, 0.60 mmol) in anhydrous methylene chloride (3 ml), methanesulfonyl chloride (0.04 ml, 59.2 mg, 0.52 mmol) was added all at once. After 15 minutes of stirring at 5° C. to complete in situ formation of the mesylate of the compound of Step C, the dextrorotatory enantiomer of 3-hydroxymethyl-1,2,3,4-tetrahydroisoquinoline (310 mg, 1.9 mmol), anhydrous N,N-dimethylformamide (0.51 ml) and acetonitrile (1.2 ml) were added. After stirring 1/2 hour at ambient temperature, the reaction mixture was heated at 55° C. for 19 hours. Concentration in vacuo afforded an orange residue which was dissolved in ethyl acetate/water (100 ml of each) with the pH adjusted to 10 with sodium carbonate. The separated aqueous phase was extracted twice with 50 ml portions of ethyl acetate. The combined organic extracts were dried over anhydrous sodium sulfate and concentrated in vacuo to an orange semi-solid (0.7 g). Flash chromatography of the entire sample (silica gel, 40 micron mesh; eluting with ethyl acetate/hexane=1.3 volume) afforded the title compound (170 mg) as a light-orange oil. 13C NMR (CDCl3): 151.6, 151.0, 136.2, 135.3, 135.0, 133.6, 133.3, 129.0, 128.6, 127.0, 126.5, 126.1, 107.5, 62.0, 58.0, 47.6, 45.6, 42.6, 26.2, 13.1.

Provenance & Evidence