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CuReUS
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why don't you try the oxidation using lead tetracetate/Pyridine.It can be done at room temperature and I think triethylamine could be used instead of
pyridine.
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Mush
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1-propanol from methyl-propionate
Methyl propanoate synthesis:
Propanoic acid 50 mL (0.67 mole), methanol 20 mL (0.5 mole) and two mL sulfuric acids were added in the reflux system. The mixture was refluxed and
stirred with a magnetic stirer for 14 h. The product was distilled at a temperature of 70-80 °C. Then, it was extracted with ten mL of 10% NaHCO3.
The bottom layer was separated, and the top layer is dried with anhydrous Na2SO4. The product was weighed and analyzed by GC, IR and
1H-NMR Yield: 33 g (0.4 mole)
1-Propanol synthesis:
Methyl propanoate 5 mL (0.045 mol) was added in a 100 mL three neck flask with 10 g (0.45 mol) of natrium. The mixture is stirred with a
magnetic stirrer and heated with an oil bath. After sodium melting, we added ethylene glycol as a solvent. (Added as soon without removing
the reflux system). The mixture was refluxed for one hour. The product was distilled at the temperature of 90-100 °C. The product was weighed and
analyzed by GC. Yield: 2.2 g (0.035 mol).
https://www.researchgate.net/publication/313590165_Synthesis...
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Cou
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https://www.youtube.com/watch?v=T9ha_MS1S9o&t=132s
This technique (dichromate, and boil off the aldehyde before its further oxidized to carboxylic acids) works because the boiling point of the aldehyde
is far lower than either the alcohol or the carboxylic acid, due to lack of OH groups for hydrogen bonding.
works for acetaldehyde and low MW aldehydes, but gets more difficult with higher MW alcohols -> aldehydes as the boiling points of the aldehydes
and carboxylic acids get closer together. When converting large alcohols to large aldehydes, you would use a synthetic technique for converting
alcohols to aldehydes, such as pyridinium chlorochromate, DMP reagent, swern oxidation.
[Edited on 10-18-2020 by Cou]
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