N-Methyl-o-phenylenediamine → HCID 90156890, compound

Participants

Reaction Steps

To a mixture of 3-oxocyclobutanecarboxylic acid (0.5 g, 4.4 mmol) and DIPEA (2.2 mL, 13.2 mmol) in dry THF (10 mL) under N2 was added HATU (2.0 g, 5.3 mmol) and N′-methylbenzene-1,2-diamine (0.8 g, 6.6 mmol) in one portion. The reaction mixture was stirred at room temperature for 2 h and the solvent was removed under reduced pressure. AcOH (5 mL) was added and the mixture was stirred at room temperature for 2 h. The solvent was removed and the residue was partitioned between EtOAc and a 5% NaHCO3 aqueous solution. The aqueous layer was extracted with EtOAc (2×10 mL) and the combined organic layer was washed with brine, dried over anhydrous Na2SO4, filtered, and concentrated. The crude residue was purified by silica gel chromatography (eluent: 1/1, Pet ether/EtOAc) to give Intermediate 1 as a yellow solid. 1H NMR (400 MHz, CDCl3) δ 7.75-7.58 (m, 1H), 7.35-7.09 (m, 3H), 3.86-3.61 (m, 4H), 3.60-3.35 (m, 1H), 2.74 (s, 3H). MS: m/z=200.1 (M+).

Provenance & Evidence