Ethyl-4-nitrocinnamate

In benzene solution, the Z- and E-stilbenes 42 form approximately equal amounts of the two regioi-somers of the fra s-substituted spiro-oxetanes (e.g., 43 from 4-Me-42) with CA in yields of 80 to 88%. These addition reactions do not occur in acetonitrile solution and Z- and -4-methoxystilbenes do not photoreact with CA in either solvent. However, high yields of the fra s-spiro-oxetanes 44 are formed from CA with Z- or E-ethyl cinnamate, ethyl 3-nitrocinnamate, benzalacetone, or chalcone in both benzene and acetonitrile. In contrast, allyl ethyl ether, methyl methacrylate, vinyl acetate, styrene, and a-chlorostyrene all yield cyclobutanes 45 with CA in benzene solution but under the same conditions, indene and E-(3-bromostyrene afford spiro-oxetanes. Such variation in reaction site continues to be discussed in terms of the electron-donor/acceptor characteristics of the addends and the role of single electron transfer in the reaction pathway. 

Ethyl o-nitrocinnamate (1 mmol) was dissolved in triethyl phosphite (5 mmol) and heated at 170°C for 3 h. The triethyl phosphite and triethyl phosphate were removed in vacuo. The residue w as eluted through a column of silica gel using CHCI3 and the product recrystallizcd from CHCl3-hexane. The yield was 94%. 

A Preparation of a-Ethyl-m-Nitrocinnamic Acid This acid is prepared from 100 g of m-nitrobenzaldehyde, 210 g of butyric anhydride and 73 g of sodium butyrate. The crude a-ethyl-m-nitrocinnamic acid is crystallized from ethanol giving about 105 g, MP 140° to 142°C. From the filtrates there may be isolated a small amount of a stereoisomer, which when pure melts at 105° to 106°C. 

The catalyst The amount of catalyst required in an aryl bromide or iodide alkene substitution varies widely with the reactants and the reaction conditions. Most examples reported have used 1-2 mol % of palladium salt relative to the aryl halide, but much lower amounts are sufficient in some instances. In an extreme case, where very reactive p-nitrobromobenzene was added to the very active alkene, ethyl acrylate and sodium acetate was the base in DMF solution at 130 C with a palladium acetate-tri-o-tolylphos-phine catalyst in 6 h the palladium turned over 134 000 times and ethyl p-nitrocinnamate was obtained in 67% yield.63... 

Ethyl o-nitrocinnamate Methyl o-nitrocinnamate Ethyl m-nitrocinnamate Methyl m-nitrocinnamate Ethyl p-nitrocinnamate Methyl p-nitrocinnamate... 

B) Preparation of m-Amino-a-Ethylhydrocinnamic Acid A mixture of 50 g of a-ethyl-m-nitrocinnamic acid, 9.1 g of sodium hydroxide, 600 cc of water and 5 teaspoons of Raney nickel catalyst is shaken at 32°C in an atmosphere of... 

Olefinic esters may be obtained directly by the Knoevenagel reaction. Alkyl hydrogen malonates are used in place of malonic acid. Decarboxylation then gives the ester directly as in the preparation of ethyl 2-heptenoate (78%) and methyl m-nitrocinnamate (87%). Alkyl hydrogen malonates are readily available by partial hydrolysis of dialkyl malonates. The use of malonic ester in the condensation leads to olefinic diesters, namely, alkylidenemalonates such as ethyl heptylidenemalonate (68%). A small amount of organic acid is added to the amine catalyst since the salts rather than the free amines have been shown to be the catalysts in condensations of this type. Various catalysts have been studied in the preparation of diethyl methylenemalonate. Increased yields are obtained in the presence of copper salts. Trimethylacetalde-hyde and malonic ester are condensed by acetic anhydride and zinc chloride. Acetic anhydride is also used for the condensation of furfural and malonic ester to furfurylidenemalonic ester (82%). ... 

C11H11N04 ethyl 4-nitrocinnamate, predominantly trans 953-26-4 25.00 1.2707 2 21975 C11H13N02 4-(dimethyiamino)cinnamic acid 1552-96-1 25.00 1.1775 2... 

CCRNOj) It yel ndls(from aq acet), mp 150 -53° readily sol in acet or ethyl acetate sol in MeOH, benz or AcOH diffc sol in petr eth was obtd, in addn to allo-ochloro -p-nitrocinnamic acid, when allo-ochloro-cinnaraic acid [CgHg.CH C(Cl),COOH] was nitrated with fuming HNO, or by nitrating normal ochlorocinnamic acid at 20-25° instead of in the cold(Refs 1 3) ... 

The bright yellow color of the solution changes to light green after saturation with carbon monoxide. The presence of carbon monoxide prevents decarbonylation of the acylpalladium complex and thus the formation of ethyl p-nitrocinnamate. 

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