That's a nifty one. It's tittilating enough to make me spill the beans on the benzaldehyde prep I was going to spring as a surprise, a gem I dug out of my old chem texts. The proper way to introduce this would of course bee in a synth report, but my lab agenda is way beehind at the moment, so here it is:
You can make benzaldehyde by heating calcium benzoate with calcium formate. The first source I read on this implied you had to use the double salt, calcium benzoate formate, or in other words the organic acids both had to be salted on the same calcium atom, but later readings indicate you can use an intimate equimolar mix of the individual salts, calcium benzoate and calcium formate. Naturally, I was going to bring this out in the context of the elusive fabled benzoic acid to meth synth, and if people harass me too much for specific citations and documentation, guess I'll still have to run it myself, and give myself as the authority.
Meditation: Whether you can make, say, 3,4,5-trimethoxy benzaldehyde from 3,4,5-trimethoxy benzoic acid calcium or barium salt, and calcium or barium formate, I haven't the froggiest idea. Haven't even done the first one yet, simple benzoic acid. Or whether any of the various tars I've produced in my speckled career could have been rescued by an acid permanganate oxidation to the aryl acid, salted with lime and then dry distilled with calcium formate for the aldehyde, only the chem gods know.
turning science fact into <<science fiction>>