HCID 66935459, compound → HCID 66935781, compound

Participants

Reaction Steps

To a solution of 5-chloro-6-diethylamino-nicotinic acid ethyl ester (2.96 g, 11.5 mmol) in dioxane (50 mL), Pd(dppf) (470 mg, 0.576 mmol) is added under argon. To this mixture, diethyl zinc (8.53 g, 69.1 mmol, as a 1.1 M solution in toluene) is added dropwise. The mixture is stirred at 75° C. for 16 h before another portion of Pd(dppf) 94 mg, 0.115 mmol) and diethyl zinc (1.42 g, 11.5 mmol, as a 1.1 M solution in toluene) is added. Stirring is continued at 75° C. for 24 h. The reaction mixture is cooled to rt and carefully quenched with water. The mixture is filtered over celite and the filtrate is extracted twice with EA. The combined org. extracts are dried over MgSO4, filtered and concentrated. The crude product is purified by CC (heptane:EA 9:1) to give 6-diethylamino-5-ethyl-nicotinic acid ethyl ester (2.40 g) as a colourless oil; LC-MS: tR=0.78 min, [M+1]+=251.19; 1H NMR (CDCl3): δ 1.15 (t, J=7.0 Hz, 6H), 1.27 (t, J=7.3 Hz, 3H), 1.40 (t, J=7.3 Hz, 3H), 2.65 (q, J=7.5 Hz, 2H), 3.36 (q, J=7.0 Hz, 4H), 4.37 (q, J=7.0 Hz, 2H), 7.99 (d, J=2.3 Hz, 1H), 8.76 (d, J=2.3 Hz, 1H).

Provenance & Evidence