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Novel Discourse | |||
All 4 posts | Subject: 4-Me-3-OH-phenylacetone from o-cresol in two steps | Please login to post | Down | |||||
Antoncho (Official Hive Translator) 02-09-04 16:09 No 487486 |
4-Me-3-OH-phenylacetone from o-cresol in two steps (Rated as: good read) |
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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 С 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 С 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 С (ифер 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 |
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dioulasso (Newbee) 02-09-04 21:50 No 487519 |
For similar reaction see also: | |||||||
http://orgsyn.org/orgsyn/prep.asp?prep=cv7p0229 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 https://www.rhodium.ws/chemistry/lead.tetraacetate.html 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. " |
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azole (One Remarkable HyperLab Bee) 02-10-04 15:20 No 487692 |
The refs. requested (in German) (Rated as: good read) |
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Here are the articles mentioned in Post 419906 (Potter: "3-HO-4-Me-P2P из о-крезола", 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_88_298.djvu) 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_88_1069.djvu) |
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azole (A Truly Remarkable HyperLab Bee) 10-11-04 11:56 No 535332 |
more articles by F. Wessely (Rated as: excellent) |
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< 3-Hydroxy-4-methylbenzaldehyde from 2,5-dimethylphenol in 2 steps > originally found by Potter (Post 414525 (Potter: "3-гидрокси-4метилбензальдегид", 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. |
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