Diisopropylethylamine → 1-Chloro-4-(rac-2,5-trans-dimethylpiperazine-1-yl)pyrido[3,4-d]pyridazine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To 1,4-dichloropyrido[3,4-d]pyridazine 3 (4.80 g, 24.0 mmol) and Hünig's Base (14.7 ml, 84.0 mmol) in NMP (10 ml) was added (2R,5S)-2,5-dimethylpiperazine (4.11 g, 36.0 mmol). The reaction was stirred at 100° C. After 2 h, the reaction contents were poured into saturated sodium bicarbonate (10× volume) and extracted with dichloromethane (4×50 mL). Silica gel chromatography (gradient 0 to 2.5% MeOH in 30% EtOAc in CH2Cl2 with 2.5% TEA additive) provided 1.4 g of 1-chloro-4-(rac-2,5-trans-dimethylpiperazine-1-yl)pyrido[3,4-d]pyridazine 43. 1H NMR (500 MHz, CDCl3) δ ppm 9.66 (s, 1H) 9.08 (d, J=5.6 Hz, 1H) 7.97 (d, J=5.6 Hz, 1H) 3.77 (tdd, J=11.8, 5.9, 3.4 Hz, 1H) 3.43 (dd, J=12.1, 2.6 Hz, 1H) 3.17-3.32 (m, 2H) 2.91 (dd, J=10.5, 2.0 Hz, 1H) 2.74 (dd, J=11.7, 10.3 Hz, 1H) 1.13 (d, J=6.1 Hz, 3H) 1.12 (d, J=6.6 Hz, 3H).

Herkunft & Nachweise