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AlCl3 and Md compounds

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Kinetic:
Vibrating_Lights, what are you trying to do with AlCl3 and the methylenedioxy bridge? Are you trying to acylate 1,3-benzodioxole? It seems from this thread that this will definitely not work with AlCl3, and not with TiCl4 in DCM either. However, if AlCl3 doesn't affect hydroxies, you could acylate catechol. I assume it doesn't because in the link I give below there is a demethylation using AlI3 in which the hydroxy stays intact. My question is:

Could you use a method of forming the methylenedioxy bridge (such as those in https://www.thevespiary.org/rhodium/Rhodium/chemistry/methylenation.html#DCM) without affecting the ketone of the molecule? This would give the interesting (for me) 3,4-(Methylenedioxy)propiophenone.

PrimoPyro:
Will have a very low yield if any at all. The phenolic protons will interfere, and also both of those hydroxy groups are electron withdrawing groups, and will inhibit Friedel-Crafts reactions by diminishing the attraction of the electrophile toward the ring.

PrimoPyro
Will perform sexual favors for females in exchange for 1,2-dimethylaziridine. PM for details.

Vibrating_Lights:
I found a ref that would Preform a pinicol rearrangement on aromatic epoxides.  I'll FInd it and post the link.  IN the procedure ANhydrous AlCl3 was added to epoxide without solvent. I was thinking that one could mix the epoxide with NaHCO2 to neutralize the hcl as it is formed when the Hcl is produced.  I think the probvlem with the AlCl3 is the Hcl correct.  It would eat the bridge???
VL_
So much game I could sell a hooker some pussy
Vl_

Osmium:
Huh?

> I think the probvlem with the AlCl3 is the Hcl correct.
>  It would eat the bridge???

No. The AlX3 will eat the bridge, not the HCl produced during workup.


I'm not fat just horizontally disproportionate.

Antoncho:
Here's some useful info from the russian article Rhodium sent me yesterday. It talks about acylating various substrates, methylendioxybenzene among them.

The other ones are :

Here's the typical synthetic proc (all the same for each one, the only difference being the catalyst and the temperature.

To a mixtr of 25mls unhydrous CH2Cl2, 37mmoles of the acylated comp'd, 37mmoles acyl chloride kept at specified temperature, there's added over the course of 0,5hrs 40mmoles anhydrous Friedel-Crafts catalyst. The rxn is further stirred 1h at 20 C, poured onto ice, acidified w/HCl , xtracted w/DCM, pooled xtracts washed w/water, dried and the solvt removed.

1,3-benzodioxole: catalyst - SnCl4, temp = 0 C
all the others: catalyst - AlCl3, temp = -10 C

Yield for methylenedioxypropiophenone - 58% (almost the worst of them all, generally the yields are 60-70%)



A great article, shall i say!


Antoncho

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