3,5-dichlorophenol

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

Procedure: Dissolve 3,5 dichlorophenol (1 kg, 6.13 mol) in 3 L dimethylformamide (DMF) and cool to 0° C. Add imidazole (918.74 g, 6.75 mol), followed by tertbutyldimethylsilyl chloride (1017.13 g, 6.75 mol). Warm the mixture to room temperature and stir for 15 minutes. Pour into water (6 L) and extract with ether (4 L). Wash the organic layer with water 2 times, 10% aqueous lithium chloride solution then brine before drying over sodium sulfate. Filter and concentrate under vacuum to obtain tert-butyl-(3,5-dichloro-phenoxy)-dimethyl-silane (1700 g) as an oil. Warm the mixture to room temperature extract with ether (4 L) Wash the organic layer with water 2 times, 10% aqueous lithium chloride solution brine before drying over sodium sulfate Filter concentrate under vacuum

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

Procedure: To a dry 3-neck round bottom flask was added 60% NaH (0.432 g, 10.81 mmol), dry THF (30 mL) and 3,5-dichlorophenol (1.76 g, 10.81 mmol). The mixture was stirred until evolution of H2 (g) ceased. Methyl 3,6-dichloropyridine-2-carboxylate N-oxide (2.0 g, 9.00 mmol) was added in one portion and stirred at RT for 3 hr, diluted with ethyl acetate and 100 mL of water. The aqueous phase was extracted with ethyl acetate (2×200 mL). The combined extracts were dried (MgSO4) and concentrated to give 2.40 g of white solid. stirred at RT for 3 hr The aqueous phase was extracted with ethyl acetate (2×200 mL) The combined extracts were dried (MgSO4) concentrated