Ethanediol mixed with conc. H2SO4 (98%) can be easily dehydrated to OH-CH=CH2 that is tuatomerized to CH3CHO (acetaldehyde) that can further undergo dehydrating polymerization in Sulfuric acid or be converted to some sulfonic acid (that'd be thermally unstable, right?). But when Ethanediol is mixed with Dry KOH in non-inert (and possibly non-dry, ambient) atmosphere, first a suspension forms, the supernatent turns yellow, then orange, and when heated above 130 degrees celsius or so, turns into deep brown-red, (with precipitate of suspension gradually dissolving). What is going on there? (hydroxy) ethandioxide cannot form with reaction with KOH, since water is more acidic than organic alcohols. Then, is the dehydration of diol going on here as well? or oxygen of atmosphere is oxidizing ethanediol in presence of base to carbonyl compounds, and then base+ carbonyl undergoing Canizzaro/ Aldol Condensation, or simply polymerization? I have observed similar effect with base+ hydroxy aldehyde/ketone as well. See my question

https://www.researchgate.net/post/why_peculiar_things_happen_when_lime_reacts_with_sugar

If this had been a temporary acid-base adduct, neutralizing would have converted ethanediol to colorless tranparent again upon precipitation of salt, but upon mixing of these two "darkend" solution and upon filtration, I have found an almost white powder with dark brown filtrate. Upon further wasking the powder with ethanediol and carefully evaporating ethanediol, I am left with a brilliant white powder (Acid and Base taken in stoichiometric amount to produce K2SO4) that decomposes at temeparature above boiling point of ethanediol. The brown liquid smells"sweet" but with a different aroma from ethanediol. I have no GC or MS appratus, only some FTIR apparatus that I can use (not sure whether I can find functional Groups of molecules identified from spectra). So I am left with theoretical prediction and wet-chemical methods only!