Propargyl bromide → Carbamic acid, [2-(2-propynyloxy)ethyl]-, 1,1-dimethylethyl ester (9CI)

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Reaction Conditions

Reaction Steps

The preparation of tert-butyl 2-hydroxyethylcarbamate is described in Example 80, Part A. Benzyltrimethylammonium chloride (18 g, 97 mmol) and 50% aqueous sodium hydroxide (1.5 L) were added to a solution of tert-butyl 2-hydroxyethylcarbamate (156.4 g, 970.0 mmol) in dichloromethane (2.4 L), and the mixture was stirred rapidly. Propargyl bromide (109 mL, 979 mmol), available as an 80% solution in toluene, was then added, and the reaction was stirred for three hours. The layers were separated, and the aqueous layer was cooled to ˜0° C. in an ice bath. Water was slowly added (1.2 L), and the aqueous solution was extracted with chloroform (2×300 mL). The combined organic solutions were washed with water (3×500 mL) and brine (2×500 mL), dried over sodium sulfate, filtered, and concentrated under reduced pressure to provide 173 g of tert-butyl 2-(prop-2-ynyloxy)ethylcarbamate as an orange oil, which was used without purification.

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