The series of symmetrical bis-amides 3 was formed by the reaction of N-methylisatoic anhydride (1), with the diamines 2. Reaction of 3 with phosphorus trichloride led to the formation of the symmetrical bis-(1,3,2-benzodiazaphosphorinones) (4). 4 c, 4 d and 4 e were easily hydrolyzed in moist air, leading to the formation of 5 c, 5 d and 5 e. In the presence of triethylamine, 4 c, 4 d and 4 e were allowed to react with Et 3 N ´3 HF to give the symmetrical bis-P±F derivatives 6 c, 6 d and 6 e, which could be readily oxidized by (NH 2 ) 2 C(:O) ´H2 O 2 , leading to the formation of a series of P(:O)F compounds 7 c, 7 d and 7 e. All compounds were characterized unambiguously by 1 H, 13 C, 19 F, and 31 P-NMRspectroscopy, mass spectrometry, and elemental analysis. All the bis-amides and bis-(1,3,2-benzodiazaphosphorinones), except 4 b and 4 f, exist as single conformers in common solvents such as toluene, diethyl ether, dichloromethane or chloroform. For compound 6 c, a single crystal X-ray structure analysis was conducted. The molecule displays crystallographic inversion symmetry.