Phosphanilic acid derivs anti-bacterial

Cmpds. (I) R1 = H, F or Br. R2 = H or F R3 = H or (if R1=F)F & at least one of R1, R2 and R3 is not = H Anti-bacterial, esp. active vs. Ps. aeruginosa & Salmonella schottmuelleri. a) NaNO2 (26g.) was added slowly to 2-fluoro-4-nitroaniline (60g.) in 48% HBF4 (170 ml.) at 0 deg., stirred 5 min., filtered, and washed with 48% HBF4 (30ml.), EtOH (2x60ml.), and Et2O. b) The fluoroborate (45g.) in EtOAc (250ml.), was treated with PCl3 (16ml.) and CuBr (1.0g.), warmed first to 40 deg., finally 10 mins. at 60 deg., and cooled in ice. Dild. with H2O (50 ml.), steam distilled, filtered, the filtrate evapd. to 30 ml. in vac., filtered, and the solid treated with 10% NaOH to pH8. The soln. was filtered, acidified to pH5, hydrog. over PtO2 (1.0g.) 0.08mol. H2 being used, and pptd. with AcOH, giving 2-fluoro-4-aminobenzenephosphonic acid, m.p. 250 deg., (dec.).