(Official Hive Translator)
02-09-04 17:09
No 487486
(Rated as: good read)
As requested in Post 486912 (silenziox: "For Antoncho", Novel Discourse), the literal transcription (this notion is essential since the original text is cryptic enough by itself
- so don't ask me for more details):Stage 1.
Russ. J. Chem. 1958:¹17,57383
A method of oxidizing phenols to the corresponding quinolacetates is described, using minimal qtties of AcOH (sufficient for forming a paste) and Pb(AcO)4, by adding a phenol solution in a small volume of AcOH at temp <50 C; the Pb salt is filtered and from the filtrate, quinolacetates are gotten using usual methods. Thus, upon oxidation 86g ortho-cresol, there was obtained 30g 1,2-dihydro-1-methyl-2-oxophenylacetate.
Now, I understand that this part doesn’t make much sense, unfortunately, that’ all Potter provided us with – maybee we should look at the original text, which he probably hadn’t.
Stage 2.
Variant 1.
Monatsh. Chem. 1957,88,¹3, 298-306
A variety of compounds was synthesized by condensation of 1,2-dihydro-1-Me-2-oxophenylacetate with compounds containig an active methylene group.
Thus, upon reaction of 1,2-dihydro-1-Me-2-oxophenylacetate with acetoacetic ester in presence of piperidine at 20 C, t=48h (1-2 hrs at 80-90 C), there’s formed C6H3-1-HO-2CH3-5-CH(COCH3)COOC2H5, the product is distilled at 130-140 C/0,05 mmHg.
This product was heated at 100 Ñ in 25mls 1N NaOH, yield 36%.
Variant 2.
Upon reaction of 1,2-dihydro-1-Me-2-oxophenylacetate with acetylacetone in presence of piperidine at 20 Ñ the rxn proceeds for 16 hrs (10mins at 100 C). The product, C6H3-1-HO-2CH3-5-CH(COCH3)2 is distilled at 115-120/0,05 mmHg. Yield = 89%
0,55 g of the above product was heated in 5mls 10% aq. NaOH for 2hrs at 100 C. Yeild of 4-Me-3-OH-P2P comprised 71%. B.p. – 110-120 Ñ (èôåð temperature) at 0,05 mmHg.
So…. here goes
The chemistry is absolutely weird for us, the Hive Bees, and there’s not much details.Anyway, I hope you found it interesting, although there’s very little hope that someone here will ever embark onto this synthetic route
I think it’d bee much more useful if someone could get those refs, won’t it?
Yours,
Antoncho
(Newbee)
02-09-04 22:50
No 487519
http://orgsyn.org/orgsyn/prep.asp?prep=c
This has been brought up previously on the Hive:
e.g. Post 309640 (java: "easy ketone.ArCH2COCH3", Chemistry Discourse)
It'd be interresting if one could proceed from p-Dimethoxybenzene to 2,5-Dimethoxyphenylacetone this way:
1. p-dMeOB --> 2,5-dMeO-Phenyllead triacetate
2. acetoacetic ester
3. decarboxylation --> 2,5-dMe-P2P
BTW, Pb(OAc)4 can be made ala ../rhodium /lead.te
or simply by gassing a solution of Pb(OAc)2 * 3H2O in GAA w/ Cl2 ...
Of course led compounds are toxic, so this synt wouldnt be the safest or enviromentally frendly.
" Unorthodox cooking, illicit cooking. A bit of real science, in fact. "
(One Remarkable HyperLab Bee)
02-10-04 16:20
No 487692
(Rated as: good read)
Here are the articles mentioned in Post 419906 (Potter: "3-HO-4-Me-P2P èç î-êðåçîëà", Russian HyperLab).
Über die Michael-Reaktion mit Chinolacetaten I.
F. Langer, F. Wessely
Monatsh. Chem., 88(3), 298-306 (1957). (http://hyperlab.0catch.com/Monatsh1957_
Über die Einwirkung von Bleitetraacetat auf Phenole VI.
W. Metlesics, E. Schinzel, H. Vilcsec, F. Wessely
Monatsh. Chem., 88(6), 1069-1076 (1957). (http://hyperlab.0catch.com/Monatsh1957_
(A Truly Remarkable HyperLab Bee)
10-11-04 13:56
No 535332
(Rated as: excellent)
< 3-Hydroxy-4-methylbenzaldehyde from 2,5-dimethylphenol in 2 steps >
originally found by Potter (Post 414525 (Potter: "3-ãèäðîêñè-4ìåòèëáåíçàëüäåãèä", Russian HyperLab)).
Die Reaktion von 5-Methyl-o-chinolacetaten mit Nucleophilen
J. Leitich, F. Wessely
Monatsh. Chem., 1964, 95, 116-128.
Lead tetraacetate reacts with 2,5-xylenol to give 2,5-dimethyl-o-quinol acetate. The latter can be rearranged into 3-hydroxy-4-methylbenzyl acetate, which hydrolyses to 3-hydroxy-4-methylbenzyl alcohol.
Reaktion von Chinolacetaten mit Dimethylsulfoxyd
J. Leitich, F. Wessely
Monatsh. Chem., 1964, 95, 129-146.
The action of dimethyl sulfoxide on 5-methyl-o-quinol acetates results in m-hydroxybenzaldehydes. If the 5-methyl group is replaced by a primary alkyl group, it is possible to obtain ketones. The reaction is also applicable to p-quinol acetates.
