Cesium carbonate → 3-[2-(2-Dimethylaminoethoxy)-4-methoxyphenylamino]phthalic acid dimethyl ester

Participants

Reaction Steps

A mixture of 3-iodophthalic acid dimethyl ester (1.0 g, 3.1 mmol), 2-(2-dimethylaminoethoxy)-4-methoxyphenylamine (0.65 g, 3.1 mmol), Pd2(dba)3 (0.13 g, 0.14 mmol), rac-BINAP (0.058 g, 0.093 mmol), and cesium carbonate (1.4 g, 4.3 mmol), in 6 mL toluene was heated to reflux under nitrogen for 24 hours. The reaction mixture was cooled, diluted with CH2Cl2 (10 mL), and filtered through Celite, and the filter was washed with additional CH2Cl2 (30 mL). The filtrate was evaporated, and the residue was chromatographed using a methylene chloride-methanol gradient, eluting 0.82 g of the product at 95:5 methylene chloride-methanol. This material was dissolved in methylene chloride (100 mL) and extracted with dilute aqueous HCl (3×75 mL). The combined aqueous extracts were washed with methylene chloride (3×75 mL), made basic (Na2CO3), and extracted into methylene chloride (3×75 mL). The organic phases were dried (MgSO4) and evaporated, providing 0.25 g, in 20% yield: 1H NMR (CDCl3) δ 2.28 (s, 6H), 2.70 (t, J=5.8 Hz, 2H), 3.80 (s, 3H), 3.87 (s, 3H), 3.88 (s, 3H), 4.06 (t, J=5.8 Hz, 2H), 6.46 (dd, J=8.6 Hz, J=2.5 Hz, 1H), 6.54 (d, J=2.7 Hz, 1H), 7.00 (dd, J=7.3 Hz, J=1.1 Hz, 1H), 7.09-7.23 (m, 3H), 7.87 (br, 1H).

Provenance & Evidence