methyl cyclopentanecarboxylate

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:

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

Procedure: To a solution of diisopropylamine (21 mL, 150 mmol) in THF (100 mL) was added dropwise a solution of n-butyl lithium (58 mL, 145 mmol) in hexanes at −10° C. while maintaining the temperature below 0° C. After addition, the solution was stirred for 30 min at 0° C. To this, a solution of methyl cyclopentane carboxylate (12.8 g, 100 mmol) in THF (20 mL) was added dropwise at −70° C. maintaining the internal temperature between −60 to −70° C. After addition, the reaction mixture was stirred for 30 min at −50 to −60° C. Then, a solution of 2-methoxy ethyl bromide (12.5 g, 90 mmol) in THF (20 mL) was added dropwise and the light brown suspension was stirred for 30 min at −60 to −70° C. Then, it was allowed to warm to room temperature and stirred overnight. The reaction mixture was poured into a saturated solution of ammonium chloride (250 mL) and was extracted with ether (2×100 mL). The combined extracts were washed with a saturated solution of sodium chloride (100 mL) and dried over anhydrous magnesium sulfate. After filtration of the drying agent, the solution was concentrated under vacuum to afford 16.55 g of crude product as a black liquid. Distillation at 70-75° C./1.5 mm Hg afforded 7.98 g of a colorless oil and a further 2.76 g as a light yellow oil for a total yield of 10.74 g (64%). HR MS (C10H18O3): Obs. mass, 186.1257. Calcd. mass, 186.1256 (M+). while maintaining the temperature below 0° C After addition maintaining the internal temperature between −60 to −70° C After addition the reaction mixture was stirred for 30 min at −50 to −60° C the light brown suspension was stirred for 30 min at −60 to −70° C to warm to room temperature stirred overnight was extracted with ether (2×100 mL) The combined extracts were washed with a saturated solution of sodium chloride (100 mL) dried over anhydrous magnesium sulfate After filtration of the drying agent the solution was concentrated under vacuum to afford 16.55 g of crude product as a black liquid Distillation at 70-75° C./1.5 mm Hg

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

Procedure: To a solution of diisopropylamine (225 mmol, 31.6 mL) in THF (150 mL) was added dropwise a solution of n-butyl lithium (217.5 mmol, 87 mL, 2.5M) in hexanes at −10° C. while maintaining the temperature below 0° C. After addition, the solution was stirred for 30 min at 0° C. To this, a solution of methyl cyclopentane carboxylate (150 mmol, 19.23 g) in THF (30 mL) was added dropwise at −70° C. maintaining the internal temperature between −60 to −70° C. After addition, the reaction mixture was stirred for 1 h at −50 to −60° C. Then, a solution of 4-bromo-1-butene (142.2 mmol, 19.2 g) in THF (30 mL) was added dropwise and the light brown suspension was stirred for 1 h at −60 to −70° C. Then, it was allowed to warm to room temperature and stirred overnight. The reaction mixture was poured into a saturated solution of ammonium chloride (250 mL) and the mixture was extracted with ether (2×150 mL). The combined extracts were washed with a saturated solution of sodium chloride (150 mL) and dried over anhydrous magnesium sulfate. After filtration of the drying agent, the solution was concentrated under vacuum and the residue was distilled at 63-67° C./2.5 mm Hg to give 13.77 g (53%) of a colorless oil. HR MS (C11H16O2): Obs mass, 182.1311. Calcd mass, 182.1307 (M+). while maintaining the temperature below 0° C After addition maintaining the internal temperature between −60 to −70° C After addition the reaction mixture was stirred for 1 h at −50 to −60° C the light brown suspension was stirred for 1 h at −60 to −70° C to warm to room temperature stirred overnight the mixture was extracted with ether (2×150 mL) The combined extracts were washed with a saturated solution of sodium chloride (150 mL) dried over anhydrous magnesium sulfate After filtration of the drying agent the solution was concentrated under vacuum the residue was distilled at 63-67° C./2.5 mm Hg

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

Procedure: 1-(4-Chlorobutyl)cyclopentane carboxylic acid methyl ester was prepared from cyclopentane carboxylic acid methyl ester and 4-chloro-1-bromobutane using the procedure described in example 7 to give a 64% yield. HR MS (C11H19ClO2): Obs. mass, 218.1072. Calcd. mass, 218.1074, (M+). to give a 64% yield

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

Procedure: 1-(Cyanomethyl)cyclopentane carboxylic acid methyl ester was prepared from cyclopentane carboxylic acid methyl ester and chloroacetonitrile using the procedure described in example 7 to give a 38% yield. HR MS (C9H13NO2): Obs mass, Calcd mass, 167.0146 (M+). to give a 38% yield