Seems interesting enough, this is what your talking about right? It could probably be titrated to phosphorous acid, with hcl, I am not sure at all on that though, I was under the impression that all of the alkyl HYPOphosphites were useful for hypo reactions, calcium hypophosphite, sodium hypophosphite, potassium hypophosphite, etc. Maybe the same could be applied to all phosphites and titration, if so maybe even the same could be incorporated for this compound, couldn't find much on hpo3 in a web search, although I have to use my AOL search today, and I haven't used this FSE yet, have you tried there. Maybe this compound is even more widely aavailable, just what we want, another RP substitute