Triethylamine → Methyl 3-amino-5-chloro-2-nitrobenzoate

Beteiligte Stoffe

Reaktionsschritte

A mixture of 3-amino-5-chloro-2-nitrobenzoic acid (43.2 g) and HATU (2-(1H-7-Azabenzotriazol-1-yl)-1,1,3,3-tetramethyl uronium hexafluorophosphate Methanaminium, commercially available) (76 g) in MeOH (81 mL), Et3N (83 mL) and THF (300 mL) was stirred at room temperature for 3 h. When TLC showed no starting material, the solvent was removed in-vacuo and the residue was then diluted with EtOAc (2 L). It was then washed with brine (1 L×3) and dried over anhydrous Na2SO4, filtered and concentrated in-vacuo. The residue was then purified by silica gel chromatography eluted with EtOAc:petroleum ether=1:8 to afford the desired product as a yellow solid (29.5 g, yield 64%). 1H NMR (300 MHz, CDCl3): δ ppm 3.90 (s, 3H, s), 5.85 (br s, 2H), 6.80 (d, 1H, J=2.4 Hz), 6.90 (d, 1H, J=2.4 Hz); LC-MS: m/e=231 [M+1]+.

Herkunft & Nachweise