Potassium Carbonate → 4-(6-Methoxyquinazolin-2-yl)benzoic acid

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of 2-chloro-6-methoxyquinazoline (Intermediate 8, 200 mg, 1.03 mmol), 4-carboxyphenylboronic acid (205 mg, 1.23 mmol) and K2CO3 (370 mg, 2.68 mmol) in DEGME/H2O (7.0 mL/2.0 mL) was degassed three times under N2 atmosphere. Then PdCl2(dppf) (75 mg, 0.103 mmol) was added and the mixture was heated to 100° C. for 3 hours under N2 atmosphere. The reaction mixture was diluted with H2O (10 mL). The aqueous layer extracted with EtOAc/MeOH (v/v=10:1, 30 mL×2). Then the aqueous layer was acidified with 2M HCl to pH 6. The precipitate was collected by filtration and washed with MeOH (10 mL), dried under high vacuum to give the desired product (220 mg, yield 76%). 1H NMR (DMSO 400 MHz): δ 13.10 (brs, 1H), 9.63 (s, 1H), 8.62 (d, J=8.0 Hz, 2H), 8.10 (d, J=8.0 Hz, 2H), 8.05 (d, J=9.2 Hz, 1H), 7.70 (dd, J=9.2, 2.8 Hz, 1H), 7.60 (d, J=2.4 Hz, 1H), 3.98 (s, 3H).

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