(Stranger)
07-19-04 13:49
No 520322
After following the patent for formylation w/ Mg(MeO)2, my friend was left w a yellowish oil. All chemicals were reag. grade(except p-meophenol. But it was crystallyzed twice and were white, 5-7 cm needles. They can also be assumed as reag. grade.) and the scale was 3g p-meo phenol. is skilled at practical synthetic chemistry.
Everything went an its writtten in the patent to the last second, but after the evaporation of toluene he was left with a pale yellow oil whose identitiy was unknown to him as he was hoping for cs crystallyne solid. Is this 2-OH-4-MeO-Bzaldehyde or did he screw up the rxn.
(Hive Addict)
07-19-04 13:56
No 520324
NO this is NOT 2-OH-4-MeO-Bzaldehyde!!!
...but 2-OH-5-MeO-benzaldehyde!
Yes, a yellow oil with a pleasant smell is what you should have. Interesting to see that you obtained what seems like a reasonably pure product from it, making the cumbersome steam-distillation process unnecessary.
How do you plan to alkylate it?
http://www.mindspring.com/~rathcoombe/ho
(Stranger)
07-19-04 17:08
No 520356
That made me feel better to hear that thay lovely yellow oil is what I want :)
(I reccomend this Mg(MeO)2 route to anybody. Ist easy and high yielding. Thanx to other bees who posted the method and saved me from the messy low yield reimerr-tiemann.)
I plan alkylatin w/ MeI followed by reduction to the alcohol - halogenation of the benzylic -oh then reacting it w/cyanide and reduction w/ Na metal.
I know that Its a long long long process but I have no access to R-NO2 s to form a nitrostyrene which I REALLY would like to :(
btw does anybody know if p-methoxyphenol dissolves in benzene?
(Hive Addict)
07-20-04 00:08
No 520385
Reimer-Tiemann is not low-yielding (at least for p-methoxyphenol), only messy. Considering the necessary precursor (water, chloroform and NaOH), I think this is still a method worthy of some respect
.Also, how did you purify your end product? Did you obtain the pale oil after you removed toluene by distillation, or did you distill the benzaldehyde? On several occasions, I obtained a yellow oil after I removed toluene by distillation. When I wanted to purify the oil, there was a very pale yellow oil comming over before 2-hydroxy-5-methoxybenzaldehyde. I cannot remember at what temperature (but more than toluene) and - as usual - can't find my notes
. The very pale yellow oil has an odour very different from toluene though. The benzaldehyde mixture turns into black. Further increasing the temperature will furnish me the benzaldehyde as a pale yellow oil, pleasantly odouring and staining my hands yellow.
Aztecunnilingus Maximus
(Stranger)
07-20-04 17:50
No 520504
GC_MS : I obtained the oil after the evaporation of toluene. It is crystal clear and smells a bit like toluene.
I would steam distill it but didnt bother as it was a very small scale rxn. But the yield of the undistilled aldehyde is nearly quantitative.
Edit: And I didnt mean disrespect to the reimer-tiemann. It has always been the bridge of my dreams up to now :)