ethyl 2-(3,5-dihydroxyphenyl)acetate

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

実験手順: A solution of ethyl 3,5-dihydroxyphenylacetate (4.0 g, 20.39 mmol), benzyl bromide (4.85 ml, 6.97 g, 40.77 mmol, 2 eq) and 5.64 g (40.77 mmol, 2 eq) of K2CO3 in 100 ml of acetone is refluxed overnight. The mixture is concentrated in vacuo, then partitioned between EtOAc and H2O. The organics are dried (MgSO4) and concentrated in vacuo. This is then passed through a flash silica gel column that is slurry packed with hexanes and eluted with 10% EtOAc in hexanes. Concentration of desired fractions gives ethyl 3,5-dibenzyloxyphenylacetate which is confirmed by NMR and used directly in the next step. The mixture is concentrated in vacuo partitioned between EtOAc and H2O The organics are dried (MgSO4) concentrated in vacuo eluted with 10% EtOAc in hexanes

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 3,5-dimethoxyphenylacetate (11.0 g, 52,32 mmol) in 200 ml of CH2Cl2 is added 75 ml (25 mmol, 1.4 eq) of 1.0M BBr3 in CH2Cl2. This is then refluxed for 36 hours. The mixture is concentrated in vacuo, then partitioned between EtOAc and HCl. The organics are dried (MgSO4) and concentrated in vacuo. This is then redissolved in EtOH and HCl is bubbled in for 5 minutes and then stirred overnight at room temperature. The mixture is concentrated in vacuo, then partitioned between EtOAc and saturated NaHCO3 solution. The organics are dried (MgSO4) and concentrated in vacuo. This is then chromatographed using silica gel and eluted with Et2O. The filtrate is concentrated in vacuo to obtain ethyl 3,5-dihydroxyphenylacetate which is confirmed by NMR and used directly in the next step. This is then refluxed for 36 hours The mixture is concentrated in vacuo partitioned between EtOAc and HCl The organics are dried (MgSO4) concentrated in vacuo This is then redissolved in EtOH HCl is bubbled in for 5 minutes The mixture is concentrated in vacuo partitioned between EtOAc and saturated NaHCO3 solution The organics are dried (MgSO4) concentrated in vacuo This is then chromatographed eluted with Et2O The filtrate is concentrated in vacuo

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 3,5-dimethoxyphenylacetate (11.0 g, 52,32 mmol) in 200 ml of CH2Cl2 is added 75 ml (25 mmol, 1.4 eq) of 1.0M BBr3 in CH2Cl2. This is then refluxed for 36 hours. The mixture is concentrated in vacuo, then partitioned between EtOAc and HCl. The organics are dried (MgSO4) and concentrated in vacuo. This is then redissolved in EtOH and HCl is bubbled in for 5 minutes and then stirred overnight at room temperature. The mixture is concentrated in vacuo, then partitioned between EtOAc and saturated NaHCO3 solution. The organics are dried (MgSO4) and concentrated in vacuo. This is then chromatographed using silica gel and eluted with Et2O. The filtrate is concentrated in vacuo to obtain ethyl 3,5-dihydroxyphenylacetate which is confirmed by NMR and used directly in the next step. This is then refluxed for 36 hours The mixture is concentrated in vacuo partitioned between EtOAc and HCl The organics are dried (MgSO4) concentrated in vacuo This is then redissolved in EtOH HCl is bubbled in for 5 minutes The mixture is concentrated in vacuo partitioned between EtOAc and saturated NaHCO3 solution The organics are dried (MgSO4) concentrated in vacuo This is then chromatographed eluted with Et2O The filtrate is concentrated in vacuo

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 3,5-dimethoxyphenylacetate (11.0 g, 52,32 mmol) in 200 ml of CH2Cl2 is added 75 ml (25 mmol, 1.4 eq) of 1.0M BBr3 in CH2Cl2. This is then refluxed for 36 hours. The mixture is concentrated in vacuo, then partitioned between EtOAc and HCl. The organics are dried (MgSO4) and concentrated in vacuo. This is then redissolved in EtOH and HCl is bubbled in for 5 minutes and then stirred overnight at room temperature. The mixture is concentrated in vacuo, then partitioned between EtOAc and saturated NaHCO3 solution. The organics are dried (MgSO4) and concentrated in vacuo. This is then chromatographed using silica gel and eluted with Et2O. The filtrate is concentrated in vacuo to obtain ethyl 3,5-dihydroxyphenylacetate which is confirmed by NMR and used directly in the next step. This is then refluxed for 36 hours The mixture is concentrated in vacuo partitioned between EtOAc and HCl The organics are dried (MgSO4) concentrated in vacuo This is then redissolved in EtOH HCl is bubbled in for 5 minutes The mixture is concentrated in vacuo partitioned between EtOAc and saturated NaHCO3 solution The organics are dried (MgSO4) concentrated in vacuo This is then chromatographed eluted with Et2O The filtrate is concentrated in vacuo