tert-butyl 2-methylpropanoate

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:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: At −78° C., 34.7 ml (69.4 mmol) of a 2 M lithium diisopropylamide solution are slowly added dropwise to a solution of 10.0 g (69.34 mmol) of tert-butyl 2-methylpropionate (Example I-1) in 100 ml of tetrahydrofuran. After the addition has ended, the mixture is stirred at −78° C. for 1 h, and a solution of 15.76 g (63.04 mmol) of 4-bromobenzyl bromide in 10 ml of tetrahydrofuran is then added and the mixture is stirred at −78° C. for 1 h. The reaction is then warmed to room temperature and poured into 100 ml of 1 N hydrochloric acid, the phases are separated and the aqueous phase is extracted 3× with diethyl ether. The combined organic phases are washed with NaHCO3 solution, dried over sodium sulphate and freed from the solvent under reduced pressure. Distillative purification of the residue under oil pump vacuum gives 16.75 g (85%) of tert-butyl 3-(4-bromophenyl)-2,2-dimethylpropionate. At −78° C. After the addition the mixture is stirred at −78° C. for 1 h The reaction is then warmed to room temperature the phases are separated the aqueous phase is extracted 3× with diethyl ether The combined organic phases are washed with NaHCO3 solution dried over sodium sulphate Distillative purification of the residue under oil pump vacuum

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

Procedure: With ice-cooling, a solution of 73.0 g (0.985 mol) of tert-butanol, 190 g (1.877 mol) of triethylamine and 0.573 g (0.0047 mol) of DMAP in 750 ml of dichloromethane is treated with a solution of 100 g (0.939 mmol) of isobutyryl chloride in 150 ml of dichloromethane, and the mixture is then stirred overnight. 500 ml of 2 M hydrochloric acid are then added, the aqueous phase is extracted with dichloromethane and the combined organic phases are washed with water, sat. NaHCO3 solution and sat. NaCl solution, dried over sodium sulphate and concentrated. Distillative purification of the crude product gives 65.5 g (48%) of tert-butyl 2-methylpropionate. With ice-cooling the aqueous phase is extracted with dichloromethane the combined organic phases are washed with water, sat. NaHCO3 solution and sat. NaCl solution dried over sodium sulphate concentrated Distillative purification of the crude product

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 isobutyryl chloride (47 g, 0.44 mol) in CH2Cl2 (75 ml) and tert-butanol (75 ml) at 0° C., pyridine (39.3 ml, 486 mmol) was added slowly by syringe. The mixture was allowed to warm to room temperature, stirred overnight, diluted with CH2Cl2 (400 ml) and washed with H2O, HCl (2N, two times), H2O (two times) and saturated NaHCO3. The organic phase was dried over MgSO4 and filtered. The filtrate was then concentrated under reduced pressure without heat. The resulting oil was simply distilled, collecting the fraction boiling at 128-129° C. to give tert-butyl isobutyrate, 21 (35.9 g, 56%). washed with H2O, HCl (2N, two times), H2O (two times) and saturated NaHCO3 The organic phase was dried over MgSO4 filtered The filtrate was then concentrated under reduced pressure without heat The resulting oil was simply distilled collecting the fraction boiling at 128-129° C.

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: At −78° C., 34.7 ml (69.4 mmol) of a 2 M lithium diisopropylamide solution are slowly added dropwise to a solution of 10.0 g (69.34 mmol) of tert-butyl 2-methylpropionate (Example I-1) in 100 ml of tetrahydrofuran. After the addition has ended, the mixture is stirred at −78° C. for 1 h, and a solution of 15.76 g (63.04 mmol) of 4-bromobenzyl bromide in 10 ml of tetrahydrofuran is then added and the mixture is stirred at −78° C. for 1 h. The reaction is then warmed to room temperature and poured into 100 ml of 1 N hydrochloric acid, the phases are separated and the aqueous phase is extracted 3× with diethyl ether. The combined organic phases are washed with NaHCO3 solution, dried over sodium sulphate and freed from the solvent under reduced pressure. Distillative purification of the residue under oil pump vacuum gives 16.75 g (85%) of tert-butyl 3-(4-bromophenyl)-2,2-dimethylpropionate. At −78° C. After the addition the mixture is stirred at −78° C. for 1 h The reaction is then warmed to room temperature the phases are separated the aqueous phase is extracted 3× with diethyl ether The combined organic phases are washed with NaHCO3 solution dried over sodium sulphate Distillative purification of the residue under oil pump vacuum

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: At −78° C., 34.7 ml (69.4 mmol) of a 2 M lithium diisopropylamide solution are slowly added dropwise to a solution of 10.0 g (69.34 mmol) of tert-butyl 2-methylpropionate (Example I-1) in 100 ml of tetrahydrofuran. After the addition has ended, the mixture is stirred at −78° C. for 1 h, and a solution of 15.76 g (63.04 mmol) of 4-bromobenzyl bromide in 10 ml of tetrahydrofuran is then added and the mixture is stirred at −78° C. for 1 h. The reaction is then warmed to room temperature and poured into 100 ml of 1 N hydrochloric acid, the phases are separated and the aqueous phase is extracted 3× with diethyl ether. The combined organic phases are washed with NaHCO3 solution, dried over sodium sulphate and freed from the solvent under reduced pressure. Distillative purification of the residue under oil pump vacuum gives 16.75 g (85%) of tert-butyl 3-(4-bromophenyl)-2,2-dimethylpropionate. At −78° C. After the addition the mixture is stirred at −78° C. for 1 h The reaction is then warmed to room temperature the phases are separated the aqueous phase is extracted 3× with diethyl ether The combined organic phases are washed with NaHCO3 solution dried over sodium sulphate Distillative purification of the residue under oil pump vacuum

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

Procedure: With ice-cooling, a solution of 73.0 g (0.985 mol) of tert-butanol, 190 g (1.877 mol) of triethylamine and 0.573 g (0.0047 mol) of DMAP in 750 ml of dichloromethane is treated with a solution of 100 g (0.939 mmol) of isobutyryl chloride in 150 ml of dichloromethane, and the mixture is then stirred overnight. 500 ml of 2 M hydrochloric acid are then added, the aqueous phase is extracted with dichloromethane and the combined organic phases are washed with water, sat. NaHCO3 solution and sat. NaCl solution, dried over sodium sulphate and concentrated. Distillative purification of the crude product gives 65.5 g (48%) of tert-butyl 2-methylpropionate. With ice-cooling the aqueous phase is extracted with dichloromethane the combined organic phases are washed with water, sat. NaHCO3 solution and sat. NaCl solution dried over sodium sulphate concentrated Distillative purification of the crude product

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

Procedure: With ice-cooling, a solution of 73.0 g (0.985 mol) of tert-butanol, 190 g (1.877 mol) of triethylamine and 0.573 g (0.0047 mol) of DMAP in 750 ml of dichloromethane is treated with a solution of 100 g (0.939 mmol) of isobutyryl chloride in 150 ml of dichloromethane, and the mixture is then stirred overnight. 500 ml of 2 M hydrochloric acid are then added, the aqueous phase is extracted with dichloromethane and the combined organic phases are washed with water, sat. NaHCO3 solution and sat. NaCl solution, dried over sodium sulphate and concentrated. Distillative purification of the crude product gives 65.5 g (48%) of tert-butyl 2-methylpropionate. With ice-cooling the aqueous phase is extracted with dichloromethane the combined organic phases are washed with water, sat. NaHCO3 solution and sat. NaCl solution dried over sodium sulphate concentrated Distillative purification of the crude product

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