2-ethylbutanoic 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:; See reaction.notes.procedure_details.

Procedure: tert-Butyl (R)-N-[2-[7-carbamoyl-1-(3-hydroxy-propyl)-1H-indol-5-yl]-1-methylethyl]-N-[2-[2-(2,2,2-trifluoroethoxy)phenoxy]ethyl]carbamate (2.00 g) was dissolved in dry pyridine (3 ml), and 2-ethylbutyryl chloride (0.54 g) prepared from 2-ethylbutyric acid and oxalyl chloride was added to the solution. After the mixture was stirred overnight at room temperature, a saturated aqueous sodium bicarbonate solution was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The ethyl acetate layer was washed with a saturated aqueous sodium bicarbonate solution and brine subsequently, and dried over anhydrous magnesium sulfate. The solvent was removed in vacuo, and the residue was purified by column chromatography on silica gel (eluent:hexane/ethyl acetate=2/1) to give white amorphous (R)-3-[5-[2-[N-(tert-butoxycarbonyl)-N-[2-[2-(2,2,2-trifluoroethoxy)phenoxy]ethyl]amino]propyl]-7-carbamoyl-1H-indol-1-yl]propyl 2-ethylbutyrate (1.66 g). was added to the solution the mixture was extracted with ethyl acetate The ethyl acetate layer was washed with a saturated aqueous sodium bicarbonate solution and brine subsequently dried over anhydrous magnesium sulfate The solvent was removed in vacuo the residue was purified by column chromatography on silica gel (eluent:hexane/ethyl acetate=2/1)

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

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

Procedure: Dysprosium (III) trifluoromethanesulfonate (3.66 g as a wet solid), anisole (1.08 g) and 2-ethylbutanoic acid (1.16 g) were refluxed together in 125 mL toluene with azeotropic removal of the lower water layer (Dean-Stark apparatus). After 48 hours, the mixture was cooled and extracted with 3×25 mL water, then by 2×25 mL saturated sodium bicarbonate solution. The organic layer was dried using anhydrous sodium sulfate, filtered, then concentrated down in vacuo to give para-methoxy-2-ethylbutyrophenone (0.90 g, 44% yield) as an amber-colored oil, which was practically pure by 1H NMR analysis. Removal of water from the three water extracts recovered 3.54 g as a damp, off-white solid. the mixture was cooled extracted with 3×25 mL water The organic layer was dried filtered concentrated down in vacuo

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

Procedure: Dysprosium (III) trifluoromethanesulfonate (3.66 g as a wet solid), anisole (1.08 g) and 2-ethylbutanoic acid (1.16 g) were refluxed together in 125 mL toluene with azeotropic removal of the lower water layer (Dean-Stark apparatus). After 48 hours, the mixture was cooled and extracted with 3×25 mL water, then by 2×25 mL saturated sodium bicarbonate solution. The organic layer was dried using anhydrous sodium sulfate, filtered, then concentrated down in vacuo to give para-methoxy-2-ethylbutyrophenone (0.90 g, 44% yield) as an amber-colored oil, which was practically pure by 1H NMR analysis. Removal of water from the three water extracts recovered 3.54 g as a damp, off-white solid. the mixture was cooled extracted with 3×25 mL water The organic layer was dried filtered concentrated down in vacuo

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

Procedure: Synthesis was performed from N-cycloheptylthiourea and 2-ethylbutyric acid according to Method J and D. Synthesis

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

Procedure: To an ice cold solution of 4-(trifluoromethyl)phenyl isocyanate (56.1 mg, 0.3 mmol) in THF (1.5 ml) was added 1-(4-aminopiperidin-1-yl)-2-ethylbutan-1-one (59.4 mg, 0.3 mmol), prepared via Example 14 and Example 15 using 2-ethylbutanoic acid. The reaction mixture was allowed to warm to rt and stirred overnight. 1 M HCl aqueous solution was added followed by extraction with EtOAc. Flash chromatography eluted with 50:1 DCM:MeOH followed by recrystallization from acetone afforded desired compound (64 mg, 55%) as a white solid. Mp 207.9-209.3° C. 1H NMR (400 MHz, DMSO-d6) δ 8.74 (s, 1H), 7.57 (m, 4H), 6.40 (d, J=7.6 Hz, 1H), 4.28 (brd, J=12.4 Hz, 1H), 3.96 (brd, J=13.6 Hz, 1H), 3.78-3.70 (m, 1H), 3.18 (t, J=11.6 Hz, 1H), 2.82 (t, J=11.0 Hz, 1H), 2.67-2.60 (m, 1H), 1.89 (d, J=10.8 Hz, p 1H), 1.83 (d, J=10.4 Hz, 1H), 1.56-1.42 (m, 2H), 1.42-1.31 (m, 2H), 1.31-1.16 (m, 2H), 0.83-0.75 (m, 6H). F NMR (300 M Hz, DMSO-d6) −60.324 (s). followed by extraction with EtOAc Flash chromatography eluted with 50:1 DCM MeOH followed by recrystallization from acetone