Propylphosphonic anhydride → Methyl 4-(3-chloro-5-isopropoxy-4-methoxybenzamido)-2-methylbenzoate

Participants

Reaction Conditions

Reaction Steps

A mixture of 3-chloro-5-isopropoxy-4-methoxybenzoic acid (5) (250 mg, 1.02 mmol), methyl 4-amino-2-methylbenzoate (6) (177 mg, 1.07 mmol) and TEA (150 μL, 1.07 mmol) in EtOAc (2.5 mL) was treated with T3P (50% in EtOAc) (1.63 mL, 2.55 mmol) and the mixture was heated at 60° C. for 5 h. The mixture was diluted with DCM (5 mL) and washed with 1M HCl (5 mL) followed by satd. NaHCO3 solution (5 mL). The organic solvents were removed in vacuo and the residue purified by silica gel chromatography (12 g, 0-100% EtOAc in isohexane to yield methyl 4-(3-chloro-5-isopropoxy-4-methoxybenzamido)-2-methylbenzoate (7) (167 mg, 40%): m/z 392 [M+H]+ (ES+), 390 [M−H]− (ES−). 1H NMR (400 MHz, CDCl3) δ:7.98 (1H, d), 7.78 (1H, s), 7.59-7.50 (2H, m), 7.40 (2H, dd), 4.67 (1H, sep), 3.94 (3H, s), 3.89 (3H, s), 2.62 (3H, s), 1.40 (6H, d).

Provenance & Evidence