Triethyl phosphite → (2,6-Difluorophenyl)phosphonic acid diethyl ester
Reaktionsgleichung
[F:1][C:2]1[CH:7]=[CH:6][CH:5]=[C:4]([F:8])[C:3]=1I.[CH2:10]([O:12][P:13]([O:17]CC)[O:14][CH2:15][CH3:16])[CH3:11]>>[F:1][C:2]1[CH:7]=[CH:6][CH:5]=[C:4]([F:8])[C:3]=1[P:13](=[O:17])([O:14][CH2:15][CH3:16])[O:12][CH2:10][CH3:11]Komponenten
3
Versuchsvorschrift
2,6-difluoroiodobenzene (3.0 g, 12.5 mmol) was combined with triethylphosphite (10.7 mL, 62.5 mmol) in a pressure vessel which had been flushed with nitrogen. The vessel was sealed and rotated in the photoreactor (16 bulbs —350 nm) for 20 hours. The reaction mixture was put under hi-vacuum (0.08 Torr) at 50° C. for 5 hours. A column was run in hexanes and ethyl acetate (increasing polarity as run). The top spot, which was UV active, was separated. After removing solvent, a yellow-tinted liquid was left (2.30 g, 74% yield). 1H NMR (400.14 MHz, DMSO) δ 7.72 (m), 7.21 (m, 2H), 4.10 (m, 4H), 1.25 (t, J=7.04 Hz). 31P {1H} NMR (161.97 MHz, DMSO): δ 8.23. The phosphonate can be hydrolyzed as described above to provide the corresponding phosphonic acid.