Look, look - another Knoevenagel/Henry reference...
Well I don't know about 3,4,5-trimethoxy-BA, but with 2,5-diMeO-BA and nitromethane, results are even better with EDDA than with n-BuAm...
2,5-Dimethoxybenzaldehyde (83.1g, 500 mmol) and ethylenediammonium diacetate (9.0g, 50 mmol) was dissolved with stirring in 400ml isopropanol with gentle heating until a clear solution was obtained. Nitromethane (36.6g, 600 mmol) was then added, and during the next hour the solution turned a deep orange, and stirring was discontinued. The solution was then allowed to stand at room temp for 36h, and the orange crystalline mass was broken up with a large spatula and was filtered with suction until no more liquid came through. The crystals was then washed with 100ml cold isopropanol in the buchner funnel, and sucked as dry as possible. After air drying overnight, the crispy and intensely orange 2,5-dimethoxynitrostyrene weighed 100.5g (480 mmol, 96%).BTW what would you want to do with 3,4-methylenedioxy-phenyl-2-nitro
ethene? Something like 3,4-MD-phenetylamine - is this active at all?
With EDDA, it seems impossible to make
anything from 3,4-methylenedioxy stuff - so it's nice to have a reference for using n-BuAm...
(and the yields for 3,4,5 look pretty good BTW - dunno if this could be done with EDDA..)
...Now the question: would it be of advantage to prepare n-butylammonium acetate prior to using it in said condensation (or maybe it isn't possible at all)? Or is the acidic environment needed (why then)?
Greetz A