ethyl 4-chlorobutanoate

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: According to the preparation of 69, ethyl 4-chlorobutyrate (1.36 g, 9.00 mmol) was used to yield 72 (1.34 g, 88.6%) as colorless powder.

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: To a solution of ethyl 4-chlorobutyrate (0.5 g, 3.32 mmol) in DMF (2 mL), piperidine (0.98 mL, 9.96 mmol), triethylamine (1.4 mL, 9.96 mmol) and a catalytic amount of KI were added and the resulting solution was refluxed overnight. After cooling at room temperature the solution was diluted with a saturated solution of NaHCO3 (10 mL) and extracts with Et2O (3×10 mL). The collected organic extracts were dried over Na2SO4, filtered and evaporated under vacuum to give the ethyl 4-piperidin-1-ylbutanoate as an oily residue (0.6 g, 3 mmol) pure enough for the next step. To a solution of the ester in dioxane (5 mL), few drops of 37% HCl were added and the solution was refluxed overnight. After cooling at room temperature the solvent was evaporated under vacuum and the residue was dried overnight in oven at 60° C. in vacuo. The crude 4-piperidin-1-ylbutanoic acid was dissolved in CH3OH (4 mL) and NaHCO3 (0.5 g, 6 mmol) was added. After stirring for 2 h, the precipitate was filtered off and the mother liquors concentrated to afford the intermediate sodium 4-piperidin-1-ylbutanoate (0.55 g, 2.84 mmol) as a colourless oil. 1H-NMR (DMSO-d6) δ 3.35 (m, 2H), 2.80 (m, 2H), 2.70 (m, 2H), 2.15 (t, 2H, J=3 Hz), 1.95 (m, 2H), 1.75 (m, 6H). the resulting solution was refluxed overnight The collected organic extracts were dried over Na2SO4 filtered evaporated under vacuum

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: To the suspension of 1.59 g of sodium hydride in 30 ml of anhydrous DMF, the solution of 8.13 g of 3-acetyl-2-(2-hydroxyphenyl)benzothiazoline in 30 ml of anhydrous DMF is added dropwise under nitrogen atmosphere at room temperature. After the addition, the reaction mixture is stirred for 20 minutes at room temperature. To the reaction mixture, the solution of 4.95 g of ethyl 4-chlorobutyrate in 15 ml of anhydrous DMF is added and stirred for 5 hours at 70° C. After cooling to room temperature the reaction mixture is poured into ice-water and extracted with ethyl acetate. After the addition stirred for 5 hours at 70° C After cooling to room temperature the reaction mixture extracted with ethyl acetate

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: SOCl2 (60.0 mL, 820 mmol) was added to a solution of 4-chloro-butyric acid (50.0 g, 410 mmol) in EtOH (1.2 L) at 0° C. The mixture was heated to reflux for 2 hr then cooled to room temperature and concentrated under reduced pressure to afford the crude 4-chloro-butyric acid ethyl ester. The mixture was heated to reflux for 2 hr concentrated under reduced pressure