New compounds of phosphorus fluorinated 2,4,6‐trimethylphenylazo pyridines (4a‐c) have
been synthesized in high yields via adding n‐butyl lithium in hexane to a stirred solution of
methyldiphenylphosphine oxide in dry THF at 0 °C, then cooled to around ‐78 °C, treated with
azo‐pyridines(2a‐c) and then allowed to warm at room temperature over 2 h. The isomers of
(E)‐((5‐chloro‐3,6‐difuoro‐4‐(mesityldiazenyl)pyridin‐2‐yl)methyl)diphenyl phosphine oxide
(4b) and (E)‐((3,6‐difuoro‐4‐(mesityldiazenyl)5‐methoxypyridin‐2‐yl)methyl)diphenyl
phosphine oxide (4c) can be separated on analytical HPLC: Chiralcel OD‐H column, hexane:2‐
PrOH, (9:1, v:v) mobile phase, flow‐rate, 1.0 mL/min, 25 °C, λ = 254 nm and polarimetric
detection, 20 μL injection volume. The resolution of this isomers were 2.12, 1.84, respectively.
د. زينب حسيني | Dr. Zineb Hacini | 11005