2,2,6-trimethyl-1,3-dioxin-4-one

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 mixture of 6.70 g of 2-trimethylsilylethanol (56.7 mmol) and 8.05 g of 2,2,6-trimethyl-4H-1,3-dioxin-4-one (56.7 mmol) was placed in a round bottom flask equipped with a short distillation apparatus and heated to to drive off acetone. The calculated amount of acetone was collected, and the residue was distilled under reduced pressure. The fraction boiling at 106-110° C. (5-10 mmHg) was collected (8.52 g, 74%). The product was used in the next step after spectral characterization. was placed in a round bottom flask equipped with a short distillation apparatus heated The calculated amount of acetone was collected the residue was distilled under reduced pressure The fraction boiling at 106-110° C. (5-10 mmHg) was collected (8.52 g, 74%)

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

Procedure: A mixture of 6.70 g of 2-trimethylsilylethanol (56.7 mmol) and 8.05 g of 2,2,6-trimethyl-4H-1,3-dioxin-4-one (56.7 mmol) was placed in a round bottom flask equipped with a short distillation apparatus and heated to drive off acetone. The calculated amount of acetone was collected, and the residue was distilled under reduced pressure. The fraction boiling at 106-110° C. (5-10 mmHg) was collected (8.52 g, 74%). The product was used in the next step after spectral characterization. was placed in a round bottom flask equipped with a short distillation apparatus heated The calculated amount of acetone was collected the residue was distilled under reduced pressure The fraction boiling at 106-110° C. (5-10 mmHg) was collected (8.52 g, 74%)

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

Procedure: 5-(4-Chlorophenyl)-3-(3-hydroxypropyl)-1-(4-methoxyphenyl) pyrazole (1.71 g, 0.005 moles) and 2,2,6-trimethyl-1,3-dioxen-4-one (0.71 g, 0.005 moles) were dissolved in 100 ml of xylenes. The solution was stirred under reflux for 16 hours. At that time, the solution was cooled to room temperature, and concentrated in vacuo to a yellow oil. The oil was flash chromatographed on silica gel to afford 59 (1.7 g, 80%) as a pale yellow oil. under reflux for 16 hours concentrated in vacuo to a yellow oil chromatographed on silica gel

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

Procedure: A mixture of 6.70 g of 2-trimethylsilylethanol (56.7 mmol) and 8.05 g of 2,2,6-trimethyl-4H-1,3-dioxin-4-one (56.7 mmol) was placed in a round bottom flask equipped with a short distillation apparatus and heated to to drive off acetone. The calculated amount of acetone was collected, and the residue was distilled under reduced pressure. The fraction boiling at 106-110° C. (5-10 mmHg) was collected (8.52 g, 74%). The product was used in the next step after spectral characterization. was placed in a round bottom flask equipped with a short distillation apparatus heated The calculated amount of acetone was collected the residue was distilled under reduced pressure The fraction boiling at 106-110° C. (5-10 mmHg) was collected (8.52 g, 74%)

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: Lactic acid 2,2,6,6-tetramethyl-4-piperidyl ester (5 g, 21.8 mmol) was dissolved in 100 ml of toluene. At reflux temperature, 3.1 g (21.8 mmol) of 2,2,6-trimethyl-4H-1,3-dioxine-4-one was added dropwise. After 3 hours at reflux, the solvent was distilled of in vacuo. A viscous residue was left. Yield 4.8 g (70%). was added dropwise After 3 hours at reflux the solvent was distilled of in vacuo A viscous residue was left

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

Procedure: Lactic acid 2,2,6,6-tetramethyl-4-piperidyl ester (5 g, 21.8 mmol) was dissolved in 100 ml of toluene. At reflux temperature, 3.1 g (21.8 mmol) of 2,2,6-trimethyl-4H-1,3-dioxine-4-one was added dropwise. After 3 hours at reflux, the solvent was distilled of in vacuo. A viscous residue was left. Yield 4.8 g (70%). was added dropwise After 3 hours at reflux the solvent was distilled of in vacuo A viscous residue was left