Propargyl alcohol → Prop-2-yn-1-yl 2-bromo-2-methylpropanoate

Propargyl alcohol (12.8 mL, 0.218 mol) and 2-bromoisobutyric acid (36.4 g, 0.218 mol) were dissolved in methylene chloride (150 mL). The reaction mixture was cooled in an ice-water bath and a solution of dicyclohexyl carbodiimide (45.0 g, 0.22 mol) in methylene chloride (50 mL) was slowly added while stirring. A solution of 4-dimethylaminopyridine (1.5 g) in methylene chloride (50 mL) was then added over a period of 10 min. The mixture was stirred in the cooling bath for 1 h and then at room temperature for 24 h. The precipitated dicyclohexylurea was filtered and washed on the filter with methylene chloride (50 mL). The solvent was removed on a rotary evaporator and the product was distilled under vacuum. Yield: 33.0 g (0.161 mol, 74%). 1H NMR spectrum in CDCl3 (δ, ppm): 4.77 (d, 2H, CH2O), 2.51 (t, 1H, C≡CH), and 1.96 (s, 6H, (CH3)2C). IR spectrum (neat liquid, NaCl plates): 3296 cm−1 (ν≡C—H), 2131 cm−1 (νC≡C), and 1741 cm−1 (νC═O).

1. temperatureThe reaction mixture was cooled in an ice-water bath
2. stirringThe mixture was stirred in the cooling bath for 1 h
3. filtrationThe precipitated dicyclohexylurea was filtered
4. washwashed on the
5. filtrationfilter with methylene chloride (50 mL)
6. customThe solvent was removed on a rotary evaporator
7. distillationthe product was distilled under vacuum

ORD record

ord-1893f28834f14f6788d4bd8c3f97a9a7

Source dataset

uspto-grants-2010_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07795355B2