joe_aldehyde
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CTH (Pd/C, KCOOH) problems
i've recently tried a CTH procedure from rhodium with degussa 10% Pd/C catalyst and KCOOH on a certain nitroalkane, and the first run had low
yields, while the second run yielded nothing even though it had the same reaction conditions. when mixing the reagents in the second attempt, the
nitroalkane somehow turned baby blue - shouldn't this only happen in alkaline aqueous environment, forming nitronate salts? anyways, in the end,
there was just red tar from an initially light yellow starting material.
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IPN
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How pure was the KCOOH and nitroalkane? And how long reaction times did you use?
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joe_aldehyde
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the nitroalkane purity wasn't determined, it came straight from a C=C reduction with NaBH4, KCOOH was prepared by neutralizing a KOH solution
with 99% formic acid. reaction time was about 6 hours. the solvent was IPA and it was heated to reflux during rxn time.
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transformer
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It seems that your nitroalkene was either not propperly reduced or your nitroalkane was of insufficient purity.
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