Nitrostyrenes from Cinnamic Acids

[Rhodium]

A Nitro-Hunsdiecker Reaction: From Unsaturated Carboxylic Acids to Nitrostyrenes and Nitroarenes
Jaya Prakash Das, Pradipta Sinha, and Sujit Roy

Org. Lett. 4, 3055-3058 (2002)

(https://www.thevespiary.org/rhodium/Rhodium/pdf/cinnamicacid2nitrostyrene.pdf)

Supporting Information

(http://pubs.acs.org/subscribe/journals/orlef7/suppinfo/4/i18/ol0262901/ol0262901_s1.pdf)
DOI:

10.1021/ol0262901

Abstract
The nitrodecarboxylation of aromatic alpha,beta-unsaturated carboxylic acids and ring-activated benzoic acids can be achieved using nitric acid (3 equiv) and catalytic AIBN (2 mol %) in MeCN.

[GC_MS]

Very interesting reaction!  

For instance:

http://fachschaft.cup.uni-muenchen.de/~schleifi/reaktion/reaction/perkin.html

[Rhodium]

Synthesis of Cinnamic Acid Derivatives Using Ethanol as Solvent or Microwave Assisted Method
Rolando F. Pellón, Taimirys Mamposo, Erick Gonzalez and Osmar Calderon

Synthetic Communications 30(20), 3769-3774 (2000)

(https://www.thevespiary.org/rhodium/Rhodium/pdf/cinnamic.malonic-mw.pdf)

Abstract
A comparison study about some parameters which influence the condensation of veratraldehyde with malonic acid in the presence of piperidine using ethanol as solvent and microwave irradiation was done, the obtainment of several substituted cinnamic acids are reported.

[ning]

as mentioned in an earlier post, you could condense benzaldehyde with acetonitrile or ethyl acetate and hydrolyze it to the cinnamic acid. Much more OTC.

BTW, Rhodium, what do you think about replacing that AIBN with benzoyl peroxide or H2O2/Fe(II)? That would bee extremely awesome.

http://www.chem.wisc.edu/areas/reich/handouts/NameReagents/namedreag-cont.htm

Has all the named reagents. Very handy  

[Rhodium]

replacing that AIBN with benzoyl peroxide or H2O2/Fe(II)?

I wouldn't add H2O2/Fe²⁺ to that solution (water & inorganic salts might be problematic), but benzoyl peroxide sounds OK. If you look at Fig 1, you can also see that the yields are not floored even if no radical initiator is added.

[Osmium]

AIBN and dibenzoylperoxide have different decomposition constants. You generally cannot simply substitute one radical initiator with another one and expect the same reaction rate.

[Aurelius]

there is a good article in chemical accounts that covers the kinetics of different radical initiators, but I don't have the ref with me.  If somebody actually wants it, I could post it in the next couple of days.

[Rhodium]

I'd be interested in that one, so please post it if you find it.

[ning]

this is a cool thread!

Osmium, I'm no chemist, but I think any radical initiator worth its salt should make the reaction "fast enough". Otherwise, why would chemists use it for that purpose?

Rhodium, I doubt water's a problem. That paper says they use "21.35 M HNO3", which weighs 1.345 kg/L, placing its concentration between 50 and 60% w/w according to my merck index. (wierd)

I plan to research the use of the Fenton reagent as radical initiator some more. It would certainly bee the most accesible thing the average bee could get, though benzoyl peroxide can be found by those with excessive acne...

You could basically throw in a little bit of iron powder and H2O2. The nitric acid would make the salt for you, and away you go.

Awesome topic. Combined with an OTC method of reducing nitrostyrenes, I think we could have a real winner in the mescaline dept. here.

[Osmium]

> Osmium, I'm no chemist, but I think any radical initiator worth its salt
> should make the reaction "fast enough".

You thought wrong.

> Otherwise, why would chemists use it for that purpose?

For the same reason that different hydride reducing agents were invented. Selectivity for example, and to have the desired concentration of radicals present in your reaction at different temperatures and in different solvent systems.