2- Cyanocinnamic acid

For preparation of dipolar polymers with dielectric properties and nonlinear optical applications, a piperidino-substituted a-cyanocinnamic acid was polycondensed with CDI.[551,tl54]... 

This procedure has been used by the submitters and others to prepare the following cinnamic acids from substituted benzal-dehydes o-nitrocinnamic acid (70%),2 -nitrocinnamic acid (77%),2 w-cyanocinnamic acid (71%),3 o-chlorocinnamic acid (82%),4 m-chlorocinnamic acid (53%),4 -chlorocinnamic acid (73%),4 2,4-dichlorocinnamic acid (70%),4 3,4-dichlorocinnamic acid (81%),4 w-bromocinnamic acid (31%),4 -methoxycinnamic acid (60%),4 and 3,4-dimethoxycinnamic acid (77%).4... 

L-cyanobenzenediazonium tetra-fluoroborate, A155 L-cyanobenzoic acid, AL67 cyano-l,4-benzoquinone, A i53 L-cyanocinnamic acid, AQ65 L-cyanophenol, AJll L-cyanophenylhydroxamic acid, AL92... 

The 2-pyrazolines 199 arise from the reactions of C-heteroarylhydrazo-noyl halides 27, 28b, and 30e with a-cyanocinnamic acid derivatives 198 in chloroform in the presence of triethylamine. In some cases, products 199 undergo elimination of hydrogen cyanide as soon as they are formed... 

Another novel synthesis involves the condensation of cyclopentanone with a-cyanocinnamic acid (149) to give 150 and 151." Presumably a... 

Cinnamic acid derivatives 960—see also 2,4-Dimethoxycinnamic acid esters Cinnamic acids—see Hydroxycinnamic adds, tratts-4-Hydroxy-a-cyanocinnamic acid Circular dichroism 992 Claisen condensation,... 

Two compounds of similar chemical structures and isomorphous crystal structures sometimes tend to form a molecular complex. Cocrystallization of 3-cyanocinnamic acid (photostable at room temperature, but 3-type [2-1-2] photore-active at 130 °C) and 4-cyanocinnamic acid ( 3-type [2-1-2] photoreactive) yielded crystals of a 1 1 complex, not a solid solution. This complex, however, was photostable [31] ... 

Na,Hg added in small quantities below 10" to a stirred and ice-cooled suspension of a-cyanocinnamic acid and excess boric acid in water, after the Na,Hg has been used up stirring continued until the temp, has dropped to 0 —/5-phenyl-a-cyanopropionie acid. Y 90%.— The excess H iB03 keeps the soln. just below the neutral point, and the alkali produced during the reaction is removed as Na-tetraborate (Na2B40,). (S. Wideqvist, Ark. Kemi 26A, Nr. 16 (1948).)... 

The lactone of 2,4-dihydroxy-3,3-dimethylpentanoic acid (known as pantolactone) has been successfully employed as a chiral auxiliary in several D-A reactions. For example, in conjunction with TiCl4, it provides a 92% de in the reaction of 2,3-dimethylbutadiene with a-cyanocinnamic acid. The diastereoselectivity is consistent with a chelated structure similar to that shown above for acryloyl lactate. In the absence of TiCl4, this same ester gives a 64% de of the opposite configuration. This... 

Acetals can also be used as carbonyl component in the Knoevenagel reaction Klein and Meyer923 obtained <%-cyanocinnamic acids from benzaldehyde diethyl acetal and cyanoacetic acid in boiling benzene in the absence of a catalyst. 

Arylmaleic acids. The base catalyzed reaction of arylacetonitriles with glyoxylic acid gives -cyanocinnamic acids, which are readily transformed into arylmaleic anhydrides. 

Cyanoacetyl added slowly with stirring to a soln. of benzylidene-o-toluidine in benzene, and refluxed 1.5 hrs. -cyanocinnamic acid o-toluidide (Y 86%) heated 3 min. with AlClg at 130° 3-cyano-4-phenyl-8-methyl-3,4-dihydro-carbostyril (Y 75%). F. e. s. E. Ziegler and T. Wimmer, M. 96, 1252 (1965). 

Jaskolla, T., Fuchs, B., Karas, M., and Schiller, J. 2009. The new matrix 4-chloro-alpha-cyanocinnamic acid allows the detection of phosphatidylethanolamine chloramines by MALDI-TOF mass spectrometry. 20, 867-74. 

Jaskolla, T.W., Lehmann, W.-D., and Karas, M. (2008) 4-Chloro-a-cyanocinnamic acid is an advanced, rationally designed MALDI matrix. 

Towers, M.W., Mckendrick, J.E., and Cramer, R. (2010) Introduction of 4-chloro-a-cyanocinnamic acid liquid matrices for high sensitivity UV-MALDI MS./. Proteome Res., 9, 1931-1940. 

A microfluidic reaction system has also been used for the production of prodrugs. A multichannel membrane microreactor was fabricated and tested for Knoevenagel condensation of benzaldehyde and ethyl cyanoacetate to produce a-cyanocinnamic acid ethyl ester, a known intermediate for the production of an antihypertensive drug [9]. Knoevenagel condensations of carbonylic coiiqtounds and malonic esters yield several important key products such as nitriles used in anionic polymerization, and the a,p-unsaturated ester intermediates employed in the synthesis of several therapeutic drugs that include niphendip-ine and nitrendipine. Unlike most condensation reactions. 

Polymers with other pendant photosensitive moieties such as 0-furylacrylic ester (2) or / -styrylacrylic ester (5) are highly photosensitive and have even higher photosensitivity after the addition of photosensitizers. However, the thermal stability of these polymers is inferior to that of the polymer with pendant cinnamic esters (4). Polymers with pendant benzalacetophenone (5), styrylpyridinium (6), a-cyanocinnamic ester (7) or a-phenylmaleimide (8) have high photosensitivity but they can not be sensitized. In addition, the photosensitive moieties that are used in the syntheses of these polymers are not commercially available, in contrast to cinnamic acid. 

Reaction of a-cyanocinnamates with 128 gives the 7H-thiazolo[3,2-a]-pyridine derivative 129, which upon hydrolysis in methanolic hydrochloric acid suffers cleavage of the pyridine ring to give 130.74... 

Me ester of acid, 116 7 Et esterofdcid, 64 N Hi 2-Cyanocinnam amide, 123 Me ester ofnitnle 89 Di-Me ester of acid, 44 5 NHi - 2-Cyanobenz-amide, 173 Me ester 51 Et ester, 70 65... 

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