Author Topic: 1-phenyl-2-nitroethane condensation possibiliies. (Read 231 times)

2bfrank · « **on:** October 25, 2009, 02:08:00 AM »

I have been busy at late working on clay preparation in order to experiment with microwave chem, as well as working on this project consisting of preparing

1. beta-nitrostyrene - which is easy and done, using benz, nitromethane and NaOH(aq) 95% yield. When clay prep is sorted, this can be done using styrene.
2. 1-phenyl-2-nitroethane via yeast, took 2 attempts from 2 different articles, Ist one resulted in yeast clinging to itself, and making stirring difficult and 10 minutes
into the reaction, stirring became non existant. This was done in biphasic conditions, pet ether and water, yeast and specie to be reduced, and I ended up
salvaging as much of the nitrostyrene as possible and tried another reaction, using H2O and ethanol, and Im about to do work up, and will know how succesful
this has been.
3 3-phenyl-2-nitroprop-1-ene. This is the step I am wanting to do, wanting to see if the 1-phenyl-2-nitroethane will condense with paraformaldehyde, hence I am
looking into the conditions to promote such a reaction. I am aware that if say a base removed the acidic proton of the arylnitroethane and this carbonanion at the
alpha position, if this was reacted with an alkyl halide then the an oxygen of the NO2, would add to the electrophilic carbon on the alkyliodide for instance, but I
cannot see a problem with using paraformaldehyde.

Any comments, suggestions, improvements, or down right - "Frank this is bullshit and wont work" I just would be interested in comments from you guys with the
experience many of you have.

Naf1 · « **Reply #1 on:** October 28, 2009, 10:28:03 PM »

That should not be a problem, you can indeed use an Aldol condensation (base to catalyze the enolate formation).

Quote from this paper;

V.Aldol Condensation of Nitroalkanes and Aliphatic Aldehydes
Satoshi Kambe and Heinosuke Yasuda
http://www.journalarchive.jst.go.jp/jnlpdf.php?cdjournal=bcsj1926&cdvol=41&noissue=6&startpage=1444&lang=en&from=jnlabstract

"In general, most aldehydes, especially paraformaldehyde, react conventionally with nitroalkanes in the presence of bases, giving the next higher homologs, or mixtures of them and non-distillable materials. [6][7])

6.M. M. Hollemann, Rec. trav. chim 23. 298. (1904)
7.B. M. Vanderbilt and H. B. Hass, Ind. Eng. Chem., 32 34 (1940)

2bfrank · « **Reply #2 on:** December 24, 2009, 12:17:01 AM »

Thanks Naf, this has been on hold due to factors that have changed. a new year project. Merry xmas to you all btw. Keep cool and safe, theirs morons on the road of late.- avoid if poss, imho

jon · « **Reply #3 on:** December 24, 2009, 05:29:20 PM »

well the problem ther is nitronate salts formed from bases and nitro compounds so exactly what solvents are you going to employ? i know it's stable in aqeous solution but if your talking about nuking it in zeolites it could rapidly decompose into gasses with a lot of heat and entropy (explode)
on a smaller scale no big deal on a larger one i'd take that into consideration.
have a closer look at that paper condensation, not addition of pi-pi system is what's going on and the results are nitroalcohols and not nitroalkenes

2bfrank · « **Reply #4 on:** December 24, 2009, 10:35:03 PM »

yep, i am wanting to avoid the alcohol product. Perhapa a protic base. I hear what your saying with gas formation > entropy ect. It will be small scale, but its been on hold, and i really need to think this through much more. thanks jon for the imput.

Wizard X · « **Reply #5 on:** December 26, 2009, 12:55:40 AM »

Look at...

T. Sakakibira, I. Takai, E. Ohara, R. Sudah, J. Chem. Soc., Chem. Commun. 1981, 261
T. Sakakibira, S. Ikuta, R. Sudah, Synthesis 1982, 261

And source this book if you can? 71. Aldol Reactions. http://www.divxturka.net/e-books-amp-tutorials/319665-ebooks-all-4.html The rapidshare link is dead.

Aldol Reactions provides a comprehensive up-to-date overview of aldol reactions including application of different metal enolates; catalytic aldol additions catalyzed by different Lewis acids and Lewis bases; enantioselective direct aldol additions; antibodies and enzyme catalyzed aldol additions and the recent aggressive development of organocatalyzed aldol additions. The power of each method is demonstrated by several applications in total synthesis of natural products. The pros and cons of these methodologies with regard to stereoselectivity, regioselectivity and application in total synthesis of natural products are discussed. Great importance is set to the diverse possibilities of the manual of aldol reaction to install required configurations in complicated natural product synthesis.

2bfrank · « **Reply #6 on:** December 26, 2009, 06:33:23 AM »

Thankyou, I got the aldol reaction via http://scientist-at-work.blogspot.com/search?updated-max=2009-07-23T22%3A01%3A00%2B05%3A30&max-results=30 Alot of the reagants are not at my arms lenght but I found the enzymes and proline - thronine amino acid catalysts very much of interest. I will look for the other cited material. YOu wouldn't have the doi numbers for both of those. Anyway It shouldn't be hard for me to find. Thanks again.

2bf

Quantum Dude · « **Reply #7 on:** January 02, 2010, 12:59:11 PM »

I was thinking about this route for a long time and its the first time someone shows me a paper regarding condensation with formaldehyde to alpha methylate the substrate. Thanks guys !

I attached a paper that talks about the selective reduction of the nitrostyrene to the corresponding nitro compound using PIB (prepared form benzaldehyde and o-phenylenediamine). No need for yeast or sodium borohydride. Looks good.

Author Topic: 1-phenyl-2-nitroethane condensation possibiliies. (Read 231 times)

2bfrank

1-phenyl-2-nitroethane condensation possibiliies.

Naf1

Re: 1-phenyl-2-nitroethane condensation possibiliies.

2bfrank

Re: 1-phenyl-2-nitroethane condensation possibiliies.

jon

Re: 1-phenyl-2-nitroethane condensation possibiliies.

2bfrank

Re: 1-phenyl-2-nitroethane condensation possibiliies.

Wizard X

Re: 1-phenyl-2-nitroethane condensation possibiliies.

2bfrank

Re: 1-phenyl-2-nitroethane condensation possibiliies.

Quantum Dude

Re: 1-phenyl-2-nitroethane condensation possibiliies.