3,4-Dichloroaniline → HCID 14650028, compound

Participants

Reaction Steps

A solution of 16.20 g (0.1 mol) of 3,4-dichlorobenzenamine, 16.36 g (0.11 mol) of an 80% solution of 3-bromo-1-propyne in toluene, and 17.4 ml (0.11 mol) of N-ethyl-N-(1-methylethyl)-2-propanamine in 350 ml of toluene is heated at 90° for six hours. Ethyl acetate is added to the reaction suspension, and the suspension is washed three times with water. The organic layer is separated, dried (magnesium sulfate), and concentrated to give 19.85 g of a dark brown liquid. This is applied to a column of 1 kg of flash silica gel packed in hexane/dichloromethane (5:1). Elution with the same solvent gives 1.48 g (11.3%) of 3,4-dichloro-N,N-di-2-propynylbenzenamine as a yellow oil which crystallizes on standing; mp 48°-50° C. Further elution gives 15.80 g (79%) of the desired product as a gold liquid. NMR (200 MHz, DMSO) δ=3.13 (t, J<3 Hz, 1, C≡CH), 3.92 (d, J<3 Hz, 2, CH2), 6.48 (br s, 1, NH, disappears on D2O addition), 6.64 (dd, J=8.9 Hz, 2.8 Hz, 1, 6H), 6.84 (d, J<3 Hz, 1, 2H), 7.32 (d, J=8.9 Hz, 1, 5H); MS (DEI): m/e=199 (M+); IR (LF): =3297, 1601, 1494 cm-1.

Provenance & Evidence