2-Butynoic acid → HCID 86661972, compound

Participants

Reaction Conditions

Reaction Steps

As shown in step 24-ii of Scheme 24, to a solution of but-2-ynoic acid (833.6 mg, 9.915 mmol) in DCM (12 mL) at 0° C. was added 1-chloro-N,N,2-trimethyl-prop-1-en-1-amine (1.325 g, 1.312 mL, 9.915 mmol). After stirring for 40 minutes, the reaction mixture was cooled to −78° C. and a solution of 3-[[1-(2,2,2-trifluoroethyl)pyrazol-4-yl]amino]tetrahydrofuran-3-carbonitrile (Compound 2075, 1.72 g, 6.610 mmol) and DIEA (2.563 g, 3.454 mL, 19.83 mmol) in DCM (12 mL) was added. The reaction mixture was warmed to 0° C. (ice-water bath), and after 1 hour the mixture was warmed to 23° C. After 30 min at 23° C., the reaction mixture was partitioned between water and EtOAc (100 mL each). The organics were separated (insoluble precipitate is present), washed with water then brine (100 mL each), dried (magnesium sulfate), filtered, and concentrated under reduced pressure. The residue was purified by medium pressure silica gel chromatography (0-80% EtOAc/hexanes) to provide N-(3-cyanotetrahydrofuran-3-yl)-N-[1-(2,2,2-trifluoroethyl)pyrazol-4-yl]buta-2,3-dienamide (Compound 2076, 1.48 g) as a yellow oil: ESMS (M+H) 327.20; 1H NMR (CDCl3, 300 MHz) δ 7.70 (s, 1H), 7.63 (s, 1H), 5.57 (t, J=6, 1H), 5.19 (d, J=6, 2H), 4.77 (q, J=9, 2H), 4.00 (m, 4H), 2.50 (m, 1H), 2.30 (m, 1H).

Provenance & Evidence