Spectroscopic Analysis of IVG and IVH

In the H NMR spectra of caged bicyclic phosphates FVH, the chemical shifts of aromatic protons appeared at 6.8-7.5 ppm, generally. Six proton signals corresponding to three methylene groups on the bicyclic ring appeared at 4.5 ppm as a 

The chemical shift of IVH-8 appeared at 56.7 ppm which was consistent with characterization of tetra-coordinate thiophosphate. The NMR spectrum of lVH-8 is shown in Fig. 5.21. 

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