Trifluoroacetic acid → ethyl (E)-4-[2-(2-pyrrolidinyl)ethenyl]benzoate

Participants

Reaction Steps

To a stirred solution of ethyl (E)-4-[2-[1-(tert-butoxycarbonyl)-2-pyrrolidinyl]ethenyl]benzoate (700 mg, 2.03 mmol) in CH2Cl2 (3 mL) was added TFA (3 mL) and the resulting mixture was stirred for 3 hr. The mixture was concentrated and the residue was made basic by the addition of sat. NaHCO3. The mixture was extracted with CHCl3 (2×100 mL). The combined extracts were dried over Na2CO3 and concentrated in vacuo to give 434 mg (87%) ethyl (E)-4-[2-(2-pyrrolidinyl) ethenyl]benzoate as a brown oil. 1H-NMR (CDCl3) δ 1.39 (3 H, t, J=7.3 Hz), 1.52–2.06 (4 H, series of m), 2.93–2.99 (1 H, m), 3.07–3.13 (1 H, m), 3.74 (1 H, q, J=7.3 Hz), 4.37 (2 H, q, J=7.3 Hz), 6.34 (1 H, dd, J=15.6, 7.3 Hz), 6.54 (1 H, d, J=15.6 Hz), 7.41 (2 H, d, J=8.3 Hz), 7.97 (2 H, d, J=8.3 Hz).

Provenance & Evidence