Synthesis and Characterization of Phosphonate Compounds

The air- or moisture-sensitive reactions were performed under an argon atmosphere using dry glassware. All reagents, starting materials and solvents were purchased from commercial sources and used as received. TLC was performed on silica gel plates (60 F₂₅₄) and visualised under UV light (254 and 365 nm). Reversed-phase chromatography was done on a Biotage Isolera One system using Biotage SNAP KP-C18-HS cartridges. Melting points were determined on an OptiMelt MPA100 apparatus. IR spectra were recorded on a Shimadzu FTIR IR Prestige-21 spectrophotometer. ¹H, ¹³C and ³¹P NMR spectra were recorded on a Bruker Avance Neo 400 MHz spectrometer. The chemical shifts (δ) were reported in parts per million (ppm) relative to the residual solvent peak as an internal reference (DMSO-d₆: ¹H 2.50, ¹³C 39.52; CD₃OD: ¹H 3.31, ¹³C 49.00). ³¹P shifts were referenced externally to H₃PO₄. The coupling constants (J) were expressed in Hertz (Hz). HRMS was performed on a Q-TOF Micro mass spectrometer.
The synthesis and characterisation of 4-iodo-2-vinylphenol (2a), 2-bromo-6-vinylphenol (2c), ethyl allylphosphonochloridate (3), ethyl (4-iodo-2-vinylphenyl) allylphosphonate (4a), 2-bromo-6-vinylphenyl ethyl allylphosphonate (4c) together with corresponding 3H-1,2-benzoxaphosphepine 2-oxides 6a,c and 7a,c are reported by our group in the previous paper¹⁹ (link).