Molecules: You'd better learn to live with them.
Polyphosphoric acid is a mixture of phosphoric acids and its anhydrides:
I like it as an acid catalyst in organic synthesis - a lot of people hate it because it's so thick and hard to handle. The stuff is absolutely gooey mess; when you heat it up, it gets down to about the consistency of honey. The neat thing is that lots of stuff will go into it (it is a strong acid goo, after all), but once you quench your reaction with water, your stuff will often crash out.
During a blissful few months, I cranked out a series of Fischer indoles with the stuff. Everything seemed to work!
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