2,2,3,3,4,4-hexafluoropentane-1,5-diol

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

Procedure: 4-Dimethylaminopyridine (634 mg, 5.2 mmol) was added to a solution of 2,2,3,3,4,4-hexafluoro-pentane-1,5-diol (1 g, 4.7 mmol) and tert-butyldimethylsilyl chloride (708 mg, 4.7 mmol) in methylene chloride (10 ml), and the mixture was stirred at room temperature for 16 hours. The reaction mixture was concentrated under reduced pressure, and the residue was then purified by silica gel column chromatography to give 5-(tert-butyl-dimethyl-silanyloxy)-2,2,3,3,4,4-hexafluoro-pentan-1-ol (770 mg, 50%). The reaction mixture was concentrated under reduced pressure the residue was then purified by silica gel column chromatography

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 30.8 g potassium hydroxide was dissolved in 400 ml of water, 100 g (0.4715 moles) of 2,2,3,3,4,4-hexafluoropentane-1,5-diol (prepared essentially as described supra) was added, and the resulting mixture was heated to 90° C. Over a period of one hour, 74.9 g (0.480 moles) of ethyl iodide was added to the flask via an addition funnel with rapid stirring. The reaction flask was then heated to reflux for two hours. The reaction mixture was cooled to room temperature, and the bottom product phase (87.1 g) was split away from the aqueous layer. The crude product was distilled at 6.0 mm Hg (6.0 torr) to give 58.8 g of 2,2,3,3,4,4-hexafluoro-5-ethoxypentanol distilling at 85°-91° C. (conversion=68%; yield based on converted material=76%). was added The reaction flask was then heated to reflux for two hours The reaction mixture was cooled to room temperature the bottom product phase (87.1 g) was split away from the aqueous layer The crude product was distilled at 6.0 mm Hg (6.0 torr)