Triethylamine → Naphthalene-2-yl-propynoic acid ethyl ester

Triflic anhydride (2.9 mL, 17 mmol) was added dropwise to a solution of triphenylphosphine oxide (4.8 g, 17 mmol) in 1,2-dichloroethane (40 mL) at 0° C. The resulting suspension was stirred for 15 minutes, followed by the dropwise addition of a solution of 3-naphthalen-2-yl-3-oxo-propionic acid ethyl ester (3.2 g, 12 mmol) in 1,2-dichloroethane (40 mL). After the addition was complete, triethylamine (4.0 mL, 29 mmol) was added and the reaction mixture was heated at reflux for 1 hr. The solution was cooled to room temperature, washed with water, and dried (MgSO4). The solvent was removed under reduced pressure, and the product was purified via column chromatography with silica eluting with hexane/ethyl acetate (9/1) to yield naphthalene-2-yl-propynoic acid ethyl ester (1.15 g, 37% yield) as a yellow oil. 1H NMR (CDCl3) δ 8.25 (s, 1H), 7.95 (m, 3H), 7.66 (m, 3H), 4.46 (m, 2H), 1.51 (t, 3H, J=8.0 Hz).

1. additionAfter the addition
2. temperaturethe reaction mixture was heated
3. temperatureat reflux for 1 hr
4. washwashed with water
5. dry with materialdried (MgSO4)
6. customThe solvent was removed under reduced pressure
7. customthe product was purified via column chromatography with silica eluting with hexane/ethyl acetate (9/1)

ORD record

ord-31126ea1635145a9b5623050008ac4fc

Source dataset

uspto-grants-2005_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06855722B2