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

Temperature

0 °C

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.

1. stirringthe reaction was stirred for three hours
2. customThe layers were separated
3. additionWater was slowly added (1.2 L)
4. extractionthe aqueous solution was extracted with chloroform (2×300 mL)
5. washThe combined organic solutions were washed with water (3×500 mL) and brine (2×500 mL)
6. dry with materialdried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure

ORD record

ord-a12355b036c24a278cbc1a8aaf5bbacc

Source dataset

uspto-grants-2007_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07220758B2