methyl piperazine-1-carboxylate

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

Procedure: To a solution of 4.3 g (0.03 mole) 1-carbomethoxypiperazine in 10 ml of ethanol was added 10.0 g (0.036 mole) of 4-chloro-1,1-bis-(p-fluorophenyl)-butane and 5.0 g of sodium bicarbonate. The mixture was heated at reflux for 36 hours. 100 ml of water was added. The mixture was extracted twice with Et2O. The combined extracts were dried over sodium sulphate and concentrated. The residue was dissolved in ethanol-ether and the hydrochloride was precipitated with ethanolic HCl. The solid was collected by filtration and recrystallised from propan-2-ol to give 2.2 g of 1-carbomethoxy-4-[4,4-bis(p-fluorophenyl)butyl]-piperazine hydrochloride. Melting point 192°-193° C. The mixture was heated at reflux for 36 hours The mixture was extracted twice with Et2O The combined extracts were dried over sodium sulphate concentrated The residue was dissolved in ethanol-ether the hydrochloride was precipitated with ethanolic HCl The solid was collected by filtration recrystallised from propan-2-ol

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

Procedure: To a solution of 4.3 g (0.03 mole) 1-carbomethoxypiperazine in 10 ml of ethanol was added 10.0 g (0.036 mole) of 4-chloro-1,1-bis-(p-fluorophenyl)-butane and 5.0 g of sodium bicarbonate. The mixture was heated at reflux for 36 hours. 100 ml of water was added. The mixture was extracted twice with Et2O. The combined extracts were dried over sodium sulphate and concentrated. The residue was dissolved in ethanol-ether and the hydrochloride was precipitated with ethanolic HCl. The solid was collected by filtration and recrystallised from propan-2-ol to give 2.2 g of 1-carbomethoxy-4-[4,4-bis(p-fluorophenyl)butyl]-piperazine hydrochloride. Melting point 192°-193° C. The mixture was heated at reflux for 36 hours The mixture was extracted twice with Et2O The combined extracts were dried over sodium sulphate concentrated The residue was dissolved in ethanol-ether the hydrochloride was precipitated with ethanolic HCl The solid was collected by filtration recrystallised from propan-2-ol

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

Procedure: 34.0 g (0.15 mole) of 1-carbomethoxy-4-benzylpiperazine dissolved in 300 ml of ethanol was treated with hydrogen over a palladium catalyst at 40 psi and room-temperature for 24 hours. The catalyst was removed by filtration and the solvent removed under reduced pressure. The residue was distilled, b.p. 70°-75° C. at 1.5 mmHg to give 16.0 g of 1-carbomethoxypiperazine. The catalyst was removed by filtration the solvent removed under reduced pressure The residue was distilled

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