tert-butyl (2,4,5-trichlorophenyl) carbonate

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

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

Procedure: A mixture of 1.19 g (5.00 m moles) L-3-(3,4-dihydroxyphenyl)-2-methylalanine, 1.49 g (5.00 m moles) t-butyl 2,4,5-trichlorophenylcarbonate and 6 ml dimethylformamide is flushed with nitrogen and 1.39 ml (10.0 m moles) triethylamine is added. After stirring at room temperature for 24 hours, 60 ml H2O and 4 ml 2.5 N HCl is added. The solution is extracted 3 times with 50 ml of ethyl acetate and the extract is washed 3 times with 50 ml of water and 1 time with 50 ml of saturated sodium chloride solution and is dried (MgSO4). The solvent is removed in vacuum to give 1.98 g of a blue oil. is flushed with nitrogen and 1.39 ml (10.0 m moles) triethylamine is added 60 ml H2O and 4 ml 2.5 N HCl is added The solution is extracted 3 times with 50 ml of ethyl acetate the extract is washed 3 times with 50 ml of water and 1 time with 50 ml of saturated sodium chloride solution is dried (MgSO4) The solvent is removed in vacuum

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

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

Procedure: A mixture of 1.19 g (5.00 m moles) L-3-(3,4-dihydroxyphenyl)-2-methylalanine, 1.49 g (5.00 m moles) t-butyl 2,4,5-trichlorophenylcarbonate and 6 ml dimethylformamide is flushed with nitrogen and 1.39 ml (10.0 m moles) triethylamine is added. After stirring at room temperature for 24 hours, 60 ml H2O and 4 ml 2.5 N HCl is added. The solution is extracted 3 times with 50 ml of ethyl acetate and the extract is washed 3 times with 50 ml of water and 1 time with 50 ml of saturated sodium chloride solution and is dried (MgSO4). The solvent is removed in vacuum to give 1.98 g of a blue oil. is flushed with nitrogen and 1.39 ml (10.0 m moles) triethylamine is added 60 ml H2O and 4 ml 2.5 N HCl is added The solution is extracted 3 times with 50 ml of ethyl acetate the extract is washed 3 times with 50 ml of water and 1 time with 50 ml of saturated sodium chloride solution is dried (MgSO4) The solvent is removed in vacuum

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

Procedure: T-Butyl 2,4,5-trichlorophenyl carbonate is a known compound and one method for its preparation is described in an article by W. Broadbent, J. S. Morley and B. E. Stone in the Journal of the Chemical Society (C), 1967 pages 2632-2637. Briefly, in this method a solution of phosgene in toluene is treated with 2,4,5-trichlorophenol at -10° C, followed by addition of dimethylaniline at such a rate that the reaction temperature is maintained at 5°-10° C. The mixture is heated to 20°-24° C and maintained at this temperature for 12 hours. The mixture is cooled by addition of ice and the suspension filtered. From the organic layer in the filtrate, 2,4,5-trichlorophenyl chloroformate is isolated. A solution of the crude 2,4,5-trichlorophenyl chloroformate in methylene chloride is reacted with a solution of t-butanol and quinoline in methylene chloride. The reaction mixture is maintained at 20°-24° C for 12 hours. The mixture is cooled by addition of ice and the suspension is filtered. From the organic layer in the filtrate t-butyl 2,4,5-trichlorophenyl carbonate is isolated. The reaction mixture is maintained at 20°-24° C for 12 hours The mixture is cooled by addition of ice the suspension is filtered

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

Procedure: T-Butyl 2,4,5-trichlorophenyl carbonate is a known compound and one method for its preparation is described in an article by W. Broadbent, J. S. Morley and B. E. Stone in the Journal of the Chemical Society (C), 1967 pages 2632-2637. Briefly, in this method a solution of phosgene in toluene is treated with 2,4,5-trichlorophenol at -10° C, followed by addition of dimethylaniline at such a rate that the reaction temperature is maintained at 5°-10° C. The mixture is heated to 20°-24° C and maintained at this temperature for 12 hours. The mixture is cooled by addition of ice and the suspension filtered. From the organic layer in the filtrate, 2,4,5-trichlorophenyl chloroformate is isolated. A solution of the crude 2,4,5-trichlorophenyl chloroformate in methylene chloride is reacted with a solution of t-butanol and quinoline in methylene chloride. The reaction mixture is maintained at 20°-24° C for 12 hours. The mixture is cooled by addition of ice and the suspension is filtered. From the organic layer in the filtrate t-butyl 2,4,5-trichlorophenyl carbonate is isolated. for its preparation is maintained at 5°-10° C The mixture is heated to 20°-24° C maintained at this temperature for 12 hours The mixture is cooled by addition of ice the suspension filtered

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

Procedure: A mixture of 1.19 g (5.00 m moles) L-3-(3,4-dihydroxyphenyl)-2-methylalanine, 1.49 g (5.00 m moles) t-butyl 2,4,5-trichlorophenylcarbonate and 6 ml dimethylformamide is flushed with nitrogen and 1.39 ml (10.0 m moles) triethylamine is added. After stirring at room temperature for 24 hours, 60 ml H2O and 4 ml 2.5 N HCl is added. The solution is extracted 3 times with 50 ml of ethyl acetate and the extract is washed 3 times with 50 ml of water and 1 time with 50 ml of saturated sodium chloride solution and is dried (MgSO4). The solvent is removed in vacuum to give 1.98 g of a blue oil. is flushed with nitrogen and 1.39 ml (10.0 m moles) triethylamine is added 60 ml H2O and 4 ml 2.5 N HCl is added The solution is extracted 3 times with 50 ml of ethyl acetate the extract is washed 3 times with 50 ml of water and 1 time with 50 ml of saturated sodium chloride solution is dried (MgSO4) The solvent is removed in vacuum