2,5-dimethoxybenzaldehyde iodination
hello folks.
wanted to share for future generations to come. Swin has iodinated 2,5-dimethoxybenzaldehyde with AgNO3 and I2 in methanol :
Swin took (15.3 grams/92.1mmol) of 2,5-dimethoxybenzaldehyde and dissolved it in roughly 350cc of methanol (took 3-5 minutes with stirring). Then swin
added AgNO3 (16.8g/99mmol) and solid I2 (94.3g/96mmol) to the solution, filled the flask with argon, and let it stir in r.t. for 7 hours.
When those 7 hours where gone, the color which was at creamy has transformed to reddish/yellow. Swin filtered out the yellow percipitate (AgI), and
added aqueous Sodium bisulfite solution (saturated) drop by drop till only a slight yellow color remained.
Then swin evaporated the solvent under vacuum and then suspended the solid in roughly 200cc of dH2O, filtered and then rextalized from boiling
ethanol.
the product seems very clean. Swin will perform tlc later on. On mp test (with no thermometer, just a rough test) the product evaporated completly
during a solid temp (not very high), indicating a somewhat clean product.
Swin is now drying the product so swin could report yield later on, but the yield looks very promising in the 80-85% zone.
swin will update later.
[Edited on 15-11-2005 by niobium]
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