Main Index Search Register Login Who's Online FAQ Links | ||||
2 Online, 0 Active | You are not logged in |
|
Methods Discourse | |||
All 4 posts | Subject: vanillin -> TMA-2 | Please login to post | Down | |||||
phenethyl_man (Newbee) 10-05-04 03:50 No 534485 |
vanillin -> TMA-2 | |||||||
I don't believe I have seen this reaction scheme discussed on here before, but it seems like an easy route to TMA-2 using an easily accessible precursor. Search for "2-methoxyhydroquinone" gave one article posted by Rhodium that follows a similar route, however the hydroquinone rather than an aldehyde is dimethylated and it is never formylated. a. Dakin reaction on vanillin yields 2-methoxyhydroquinone. I believe H2O2 under alkaline conditions will accomplish this. b. Your choice of a phenolic ortho-formylation on 2-methoxyhydroquinone yields 2,5-dihydroxy-4-methoxybenzaldehyde. c. Dimethylation w/DMS yields Asaronaldehyde [2,4,5-trimethoxybenzaldehyde]; plenty of representative procedures of this on rhodium.ws. I shouldn't have to explain how to get to the target compound from there. Anyone see any potential problems here? - phenethylman - |
||||||||
Saddam_Hussein (Hive Bee) 10-05-04 05:55 No 534498 |
asaraldehyde | |||||||
First, you have to subject vanillin to a Dakin reaction (H2O2/NaOH), followed by methylation of the resulting phenol. 1,2,4-Trimethoxybenzene is extracted and subsequently purified by distillation, followed by Vilmeier-Haack formylation (DMF). Total yield from vanillin is 40-50%. You could also use TFSE. President of the Iraqi Chemical Weapons of Mass Destruction Development Society |
||||||||
Captain_America (Über-Führer die Ironie) 10-05-04 08:41 No 534510 |
For TMA-2 and sisters | |||||||
Nah, simply methylate vanillin, brominate and do a methoxid swap and you'll have the asaraldehyde... Post 214369 (foxy2: "2 Bromination of 3,4-dimethoxybenzaldehyde", Chemistry Discourse) in methanol Post 214376 (foxy2: "Re: 2 Bromination of 3,4-dimethoxybenzaldehyde", Chemistry Discourse) in chloroform For 2C-T and Alephs from vanillin it might bee better to make the 6-bromovanillin a la Post 529398 (Captain_America: "5-Bromo-4-formyl-2-methoxyphenol", Novel Discourse) then swap with the methoxid and transform the -OH on para to S-R by tosylation/mesylation followed by mercaptan swap... It would of bee a nice shortcut to make the 4-alkylthio vanillin following the same strategy and then go from there, but I don't know if it would give good yields in bromination step to come, if so, then good - there is no reason going via acetoxy ester. Alternative solution would bee using a nice oxidative iodination method found by Kinetic that works on less activated substrates (maybee on 4-alkylthio-vanillin), Post 518568 (Kinetic: "Iodination of arenes with KI and H2O2", Chemistry Discourse) very simple, high-yielding and perfectly OTC, good find Kinetic. |
||||||||
phenethyl_man (Newbee) 10-06-04 00:26 No 534603 |
Re: First, you have to subject vanillin to a... | |||||||
|
||||||||