Disproportionation of Hypophosphorous Acid

Aqueous hypophosphorous acid can be obtained by simple neutralization of the reaction mixture at the end of the above reaction (5B.30) with strong acid  

An alternative synthesis of hypophosphorous acid involves oxidation of phosphine with iodine in water  

The thermal decomposition of hypophosphorous acid provides a couple of perfect opportunities for sharpening our arrow-pushing skills  

An oxo-bridged intermediate is a reasonable framework to invoke to preorganize the molecules for hydride transfer  

So we now have a pentavalent P with three hydrogens and two O ligands. A second hydride transfer seems necessary to kick out one of the oxygens  

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