ethyl 2-oxo-2-phenylacetate

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:

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

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

Procedure: A total of 3.5 mL (10.5 mmol) of 3.0M phenylmagnesium bromide was added to a solution of 1.6 mL (10 mmol) of ethyl benzoylformate in THF in an analogous manner as described for the synthesis of 3,4-dihydroxy-5-methyl-5-phenyl-2(5H)-furanone to give 5,5-diphenyl-4-hydroxy-3-phenylmethoxy-2(5H)-furanone as an oil, which was purified over SiO2 using acetone/hexanes (3/7).

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

Procedure: To a 2-necked flask flame dried under argon with septum and charged with a solution of 3.6 g (20 mmol) of ethyl benzoylformate in 50 mL of anhydrous THF at -30° C. was slowly added 7 mL (21 mmol) of a 3.0 M solution of methylmagnesium iodide. The reaction mixture was stirred at 0° C. for 45 minutes, then at room temperature for 30 minutes and again cooled to 0° C. Benzyloxyacetyl chloride (3.4 mL, 21 mmol) was added and the reaction mixture was stirred at room temperature for 1 hour, cooled to -78° C. and 33 mL of a 1.5M solution of LDA in THF was added with rapid stirring. The mixture was worked up after 1 hour by the addition of 100 mL of aqueous 10% HCl solution and 300 mL of ether. The layers were separated and the organic phase was washed with 50 mL aqueous 10% HCl solution, 30 mL of H2O, and extracted with 3×40 mL of saturated NaHCO3 solution. The bicarbonate extracts were combined and washed with 40 mL of ether, acidified to pH 1 with 10% aqueous HCl solution, and extracted with 2×80 mL of ether. The organic fractions were combined, washed with 25 mL of H2O, 25 mL of brine, dried (MgSO4), and concentrated leaving 1.2 g (20% yield) of 4-hydroxy-5-methyl-5-phenyl-3-phenylmethoxy-2-(5H)-furanone as a yellow oil. To a 2-necked flask flame dried under argon with septum at room temperature for 30 minutes again cooled to 0° C the reaction mixture was stirred at room temperature for 1 hour cooled to -78° C. The layers were separated the organic phase was washed with 50 mL aqueous 10% HCl solution, 30 mL of H2O extracted with 3×40 mL of saturated NaHCO3 solution washed with 40 mL of ether extracted with 2×80 mL of ether washed with 25 mL of H2O, 25 mL of brine dried (MgSO4) concentrated