2-ethynylpiperidine;hydrochloride

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a rapidly-stirred mixture of 2-ethynylpiperidine hydrochloride (330 mg, 2.27 mmol), toluene (5 mL), and 1N NaOH (4.7 mL), cooled at 0° C., was added a solution of 2-methyl-5-phenyl-1,3-thiazole-4-carbonyl chloride (539 mg, 2.27 mmol) in toluene (8 mL) dropwise over 20 mins. The mixture was stirred at 0° C. for 20 mins, then allowed to warm to ambient temperature. After 1 h, the solution was diluted with EtOAc and the layers separated. Brine was added to the aqueous layer and it was extracted with EtOAc. The combined organics were dried over magnesium sulfate, filtered, and concentrated in vacuo. The crude material was purified by silica gel flash chromatography eluting with 0-50% EtOAc in hexanes to provide (2-ethynylpiperidin-1-yl)(2-methyl-5-phenyl-1,3-thiazol-4-yl)methanone as an orange foam. The compound gave a mass ion (ES+) of 311.2 for M+H+. 1H NMR δ (ppm) (CDCl3): 7.44-7.50 (2 H, m), 7.31-7.39 (3H, m), 5.78 (1H, s), 4.58 (1H, d, J=13.6 Hz), 3.33 (1H, d, J=11.2 Hz), 2.99-3.10 (1H, m), 2.73 (3H, s), 2.30 (1H, dd, J=22.0, 3.2 Hz), 1.55-2.04 (4H, m), 1.36-1.42 (1H, m), 1.20-1.28 (1H, m), 0.87-0.97 (1H, m). to warm to ambient temperature After 1 h the layers separated Brine was added to the aqueous layer and it was extracted with EtOAc The combined organics were dried over magnesium sulfate filtered concentrated in vacuo The crude material was purified by silica gel flash chromatography eluting with 0-50% EtOAc in hexanes

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a rapidly-stirred mixture of 2-ethynylpiperidine hydrochloride (329 mg, 2.26 mmol), toluene (5 mL), and 1N NaOH (4.7 mL), cooled at 0° C., was added a solution of 5-methyl-2-(2H-1,2,3-triazol-2-yl)benzoyl chloride (500 mg, 2.26 mmol) in toluene (8 mL) dropwise over 20 mins. The mixture was stirred at 0° C. for 20 mins, then allowed to warm to ambient temperature. After 1 h, the solution was diluted with EtOAc and the layers separated. Brine was added to the aqueous layer and it was extracted with EtOAc. The combined organics were dried over magnesium sulfate, filtered, and concentrated in vacuo. The crude material was purified by silica gel flash chromatography eluting with 0-60% EtOAc in hexanes to provide (2-ethynylpiperidin-1-yl)[5-methyl-2-(2H-1,2,3-triazol-2-yl)phenyl]methanone as a collapsing white foam. The compound gave a high resolution mass spectrum (ES+) m/z of 259.1553, calculated for M+H+ [C17H18N4O: 295.1553]. 1H NMR δ (ppm) (CDCl3): 7.75-7.86 (3H, m), 7.30-7.34 (1 H, m), 7.18-7.20 (1H, m), 5.76 (1H, d, J=33.6 Hz), 4.50-4.67 (1H, m), 3.20-3.31 (1H, m), 2.91-3.08 (1H, m), 2.43 (3H, s), 2.04-2.36 (1H, m), 1.64-1.91 (2H, m), 1.42-1.61 (1H, m), 1.30-1.37 (1H, m). to warm to ambient temperature After 1 h the layers separated Brine was added to the aqueous layer and it was extracted with EtOAc The combined organics were dried over magnesium sulfate filtered concentrated in vacuo The crude material was purified by silica gel flash chromatography eluting with 0-60% EtOAc in hexanes