Diisopropylamine → (3,5-Dichloro-phenyl)-propynoic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

To a solution of diisopropylamine (0.23 mL) in THF (0.6 mL) at −78° C. was added a solution of n-butyllithium (0.46 mL, 2.0 M in hexane). The mixture was stirred at −78° C. for 20 minutes, 0° C for 15 min., and cooled to −78° C. To this mixture was added a solution of 1,3-dichloro-5-ethynyl-benzene (136 mg, 0.80 mmol) in THF (1.0 mL) over 2 minutes. After stirring at −78° C. for 1 h, a solution of ethyl chloroformate (0.09 mL) in THF (0.2 mL) was added, and stirred for 1 h at −78° C. The reaction was quenched with saturated ammonium chloride, warmed up to ambient temperature, and extracted with ethyl acetate. The extract was dried over Na2SO4, concentrated, and flash chromatographed on silica gel, eluting with hexane to give the title compound (0.16 g, 87% yield) as a yellow oil. 1H NMR (CDCl3) δ 7.47-7.44 (m, 3H), 4.31 (q, 2H, J=7.2 Hz), 1.36 (t, 3H, J=7.2 Hz).

Provenance & Evidence