Trifluoroacetic acid → 4-(9'-Cyclopentyl-5'-methyl-6'-oxo-5',6',8',9'-tetrahydrospiro[cyclobutane-1,7'-pyrimido[4,5-b][1,4]diazepine]-2'-ylamino)-3-fluorobenzoic acid

Participants

Reaction Steps

2′-Chloro-9′-cyclopentyl-5′-methyl-8′,9′-dihydrospiro[cyclobutane-1,7′-pyrimido[4,5-b][1,4]diazepin]-6′(5′H)-one (Intermediate 4) (0.20 g, 0.63 mmol, 1 eq), 4-amino-3-fluorobenzoic acid (0.30 g, 1.9 mmol, 3 eq) and TFA (0.24 mL, 3.2 mmol, 5 eq) were heated to reflux in TFE for 18 hours. Further 4-amino-3-fluorobenzoic acid (0.20 g) and TFA (0.1 mL) were added and the reaction was heated to reflux again for 2 days. Further TFA (0.24 mL) was added and the reaction was heated to reflux again for 3 days. Solvent was evaporated in vacuo and the resulting residue was triturated with EtOAc to give 4-(9′-cyclopentyl-5′-methyl-6′-oxo-5′,6′,8′,9′-tetrahydrospiro[cyclobutane-1,7′-pyrimido[4,5-b][1,4]diazepine]-2′-ylamino)-3-fluorobenzoic acid (0.15 g, 55%).

Provenance & Evidence