SM2
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Best catalyst/medium
In the classic rxn between nitro olefin and a benzaldehyde, different catalysts work better than some depending on the nature of the olefin and
aldehyde being condensed. Let's say one is sick of using copious amounts of glacial aa, along with ammonium acetate, and one doesn't have acess to
n-butyl amine.
Is there a method which yields decent results and doesn't require tons of acetic acid/acetate? Many thanks.
(PS: you'll just have to read my mind on what olefin and aldehyde I am thinking about).
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kristofvagyok
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What reaction are you talking about? There is no such condensation what you have mentioned. Nitro olefins are hard to prepare (except larger chain
olefins), the most simple of this family (nitro-ethene) is a yellow smelly liquid what is really sensitive to anything, if it is polymerised it
usually expodes.
If you want to condense nitroALKANES and benzaldehyde with a simple nitro-aldol or henry reaction, then this thead will be reported in no time.
This simple reaction has a lot catalyst and if you would have a minimal organic chemistry knowledge, then you would know that it is really simple to
find a catalyst for that, not just t-BuNH2 and ammonium acetete is good for that.
-yes I have an idea what are you talking about and I would have a great suggestion: just go home, turn off the lights and think about that a bit that
how awesome you are, this is called popularly "mental masturbation".
Cheers.
[Edited on 8-9-2012 by kristofvagyok]
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-Pictures from chemistry, check it out(:
"You can’t become a chemist and expect to live forever." |
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SM2
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I'm just blown away by your response, kristofvagyok . All I really wanted to know is weather (in knov condensation) there is anything which is
efficient, and doesn't use gac/aa or n-butyl amine.
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kristofvagyok
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Quote: Originally posted by Fennel Ass Ih Tone  | | I'm just blown away by your response, kristofvagyok . All I really wanted to know is weather (in knov condensation) there is anything which is
efficient, and doesn't use gac/aa or n-butyl amine. |
Knoevenagel condensation won't work with nitro olefins, it will only work with nitroalkanes, but in this case it is called Henry reaction or Aldol
condensation and we will turn back to my previous post.
What are your reaction partners, what do you want to react with what? Benzaldehyde and ... ?
I have a blog where I post my pictures from my work: http://labphoto.tumblr.com/
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"You can’t become a chemist and expect to live forever." |
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Nicodem
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Thread Moved
9-9-2012 at 07:22 |
zed
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Many, many procedures have been used to produce nitro-olefins. There may be no rule for what works best.
Procedures that work very well with nitromethane, may completely fail for nitroethane.
Also, different benzaldehydes react differently. A procedure that produces a good yield for one, may work very poorly on another.
Go to the literature. Find out what has worked best for past experimenters, who were producing the specific product you are interested in.
Use the Science Madness search engine.
There is also a vast reservoir of information in "Pihkal" and the "Rhodium Archive".
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