hex-5-ynoic acid

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

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

Procedure: To a solution of 10 g (89 mmol) of 5-hexynoic acid and 31.0 mL (223 mmol) of triethylamine in 450 mL of anhydrous tetrahydrofuran at −25° C. under an atmosphere of nitrogen was added 12 mL (98 mmol) of trimethylacetyl chloride over 20 min. Upon addition a white precipitate formed and the resulting suspension was stirred for 2 h. Next, 4.2 g (98 mmol) of anhydrous lithium chloride and 17 g (94 mmol) of (S)-(−)-4-benzyl-2-oxazolidinone were added sequentially and the mixture was allowed to gradually warm to ambient temperature over 12 h. All volatiles were removed in vacuo and the residue was diluted with water (500 mL) and extracted with ether (3×200 mL). The combined organic layers were washed with brine (100 mL), dried over magnesium sulfate, filtered and concentrated in vacuo. The crude residue was purified by silica gel chromatography eluting with a 10-25% ethyl acetate in hexanes gradient to afford the title compound as a colorless solid (22 g, 93%). 1H NMR (500 MHz, CDCl3): δ 7.35-7.31 (m, 2H), 7.28-7.25 (m, 1H), 7.19-7.21 (m, 2H), 4.69-4.64 (m, 1H), 4.22-4.15 (m, 2H), 3.28 (dd, J=13.4, 3.3 Hz, 1H), 3.13-3.01 (m, 2H), 2.78 (dd, J=13.4, 9.6 Hz, 1H), 2.34-2.30 (m, 2H), 1.99 (t, J=2.7 Hz, 1H), 1.96-1.88 (m, 2H). LC-MS: m/z (ES) 272.2 (MH)+, 294.3 (MNa)+. Upon addition a white precipitate formed All volatiles were removed in vacuo the residue was diluted with water (500 mL) extracted with ether (3×200 mL) The combined organic layers were washed with brine (100 mL) dried over magnesium sulfate filtered concentrated in vacuo The crude residue was purified by silica gel chromatography eluting with a 10-25% ethyl acetate in hexanes gradient

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

Procedure: To a solution of 69.0 g (615 mmol) of 5-hexynoic acid and 214 mL (1540 mmol) of triethylamine in 1.0 L of anhydrous tetrahydrofuran at −25° C. under an atmosphere of nitrogen was added 83.0 mL (677 mmol) of trimethylacetyl chloride over 20 min. Upon addition a white precipitate formed and the resulting suspension was stirred for 2 h. Next, 28.7 g (677 mmol) of anhydrous lithium chloride and 100.0 g (615.0 mmol) of (4S)-4-phenyl-1,3-oxazolidin-2-one were added sequentially and the mixture was allowed to gradually warm to ambient temperature over 12 h. All volatiles were removed in vacuo and the residue was diluted with water (1 L) and extracted with ethyl acetate (3×300 mL). The combined organic layers were washed with brine (250 mL), dried over magnesium sulfate, filtered and concentrated in vacuo. The crude residue was purified by silica gel chromatography eluting with a 5-50% ethyl acetate in hexanes gradient to afford the title compound as a colorless solid (135 g, 85.4%). 1HNMR (500 MHz, CDCl3): δ 7.40-7.37 (m, 2H), 7.36-7.32 (m, 1H), 7.31-7.28 (m, 2H), 5.42 (dd, J=8.9, 3.7 Hz, 1H), 4.69 (t, J=8.9 Hz, 1H), 4.28 (dd, J=9.2, 3.7 Hz, 1H), 3.13-3.02 (m, 2H), 2.24-2.21 (m, 2H), 1.94 (t, J=2.6 Hz, 1H), 1.84 (quintet, J=7.1 Hz, 2H). LC-MS: m/z (ES) 258.2 (MH)+. Upon addition a white precipitate formed All volatiles were removed in vacuo the residue was diluted with water (1 L) extracted with ethyl acetate (3×300 mL) The combined organic layers were washed with brine (250 mL) dried over magnesium sulfate filtered concentrated in vacuo The crude residue was purified by silica gel chromatography eluting with a 5-50% ethyl acetate in hexanes gradient

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

Procedure: To a solution of hex-5-ynoic acid (500 mg, 4.46 mmol), DMAP (27 mg, 0.23 mmol) and EDC hydrochloride (940 mg, 4.90 mmol) in DCM (10 mL) was added morpholine (391 μL, 4.46 mmol). The reaction was stirred at RT overnight and then diluted with DCM (50 mL). The resulting solution was washed with water (3×10 mL), brine (10 mL) and aq hydrochloric acid (2 M, 2×20 mL) and was then dried, filtered and evaporated in vacuo to afford the title compound (11) (808 mg, 100%) as a yellow oil: 1H NMR (500 MHz, CDCl3) δ: 3.65-3.71 (4H, m), 3.63 (2H, d), 3.45-3.54 (2H, m), 2.46 (2H, t), 2.26-2.33 (2H, m), 1.98 (1H, t), 1.88 (2H, quin). The resulting solution was washed with water (3×10 mL), brine (10 mL) and aq hydrochloric acid (2 M, 2×20 mL) was then dried filtered evaporated in vacuo

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

Procedure: The starting material methyl 5-hexynoate was prepared by the reaction of 5-hexynoic acid with diazomethane according to Method E above.

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

Procedure: The starting material methyl 5-hexynoate was prepared by the reaction of 5-hexynoic acid with diazomethane according to Method E above.