To ethyl cinnamate

Baker s yeast catalyzed the regioselective cycloaddition of stable aromatic nitrile oxides ArCNO [Ar = 2,6-C12C6H3, 2,4,6-Me3C6H2, 2,4,6-(MeO)3C6H2] to ethyl cinnamate, ethyl 3-(p-tolyl)acrylate, and tert-butyl cinnamates (218). Reactions of dichloro- and trimethoxybenzonitrile oxides with all three esters proceeded regio- and stereoselectively to form exclusively alkyl tran.v -3,5-diary 1 -... 

Waters, H. D. C., A. R. Caverhill and P. W. Robertson The Kinetics of Halogen Addition to Unsaturated Compounds, Part XII. Iodine Catalysis of Chlorine and Bromine Addition to Ethyl Cinnamate. J. chem. Soc. (London) 1947, 1168. 

Ethyl <2,/3-dibromo-/3-phenylpropionate is prepared by adding bromine to ethyl cinnamate.1... 

The addition of stabilized nucleophiles to activated ir-systems is one of the oldest and most useful constructive methods in organic synthesis, dating back more than a hundred years. In 1887 Michael, after whom the most well-known example of this reaction was named, published the first of a series of papers on this reaction describing the addition of the sodium salt of both diethyl malonate (1) and ethyl ace-toacetate (2) to ethyl cinnamate (3) to give the products (4) and (5), respectively (equation 1).1 This Mi-... 

Initial Molar Ratio of Bromine to Ethyl Cinnamate-O-CD Complex... 

If the reaction between cinnamate 1 and hydroxylamines occurred through a concerted mechanism, the process should take place through a cyclic (five-mem-bered ring) transition state, similar to the ones proposed for [3+2] dipolar cycloadditions or retro-Cope eliminations. The cyclic transition state for the concerted addition of deuterated iV-methylhydroxylamine to ethyl cinnamate 1 is represented in Scheme 8.7 (atoms involved in the cyclization colored blue). As the nitrogen atom and the deuterium approach the C=C bond from the same side, the addition is syn, leading to intermediate 12. A rapid proton shift would give compound 3 which can be either isolated or cyclized in the presence of a Lewis acid to the isoxazolidi-none 4 by intramolecular transesterification. The stereochemistry of the products 3 and 4 is determined during the concerted addition step. 

While nucleophilic additions to C=C bonds in a,P-unsaturated systems usually take place in a conjugated fashion and through mechanisms involving polar transition states, in some cases a concerted addition of the nucleophile must be considered. The addition of hydroxylamines to ethyl cinnamate is a clear example of such an unusual type of reaction. 

As a general guide, however, it may be noted that the following have fairly easily recognisable odours methyl and ethyl formate methyl and ethyl acetate (apples) methyl and ethyl benzoate methyl salicylate (oil of winter-green) and ethyl salicylate methyl and ethyl cinnamate. (It is however usually impracticable to distinguish by odour alone between the methyl and ethyl esters of a particular acid.) Methyl and ethyl o. alate, and methyl and ethyl phthalate are almost odourless. Succinic and tartaric esters have faint odours. 

Phenylpropiolic acid. This is an example of an aromatic acetylenic acid, and is made by adding bromine to the ethylenio linkage in ethyl cinnamate, and treating the resulting dibromide with alcohobc potassium hydroxide which eliminates two molecules of hydrogen bromide ... 

The catalyst is inactive for the hydrogenation of the (isolated) benzene nucleus and so may bo used for the hydrogenation of aromatic compounds containing aldehyde, keto, carbalkoxy or amide groups to the corresponding alcohols, amines, etc., e.g., ethyl benzoate to benzyl alcohol methyl p-toluate to p-methylbenzyl alcohol ethyl cinnamate to 3 phenyl 1-propanol. 

The addition of diazomethane to unsaturated esters (1), as ethyl acrylate, methyl crotonate and ethyl cinnamate, was investigated by Auwers who showed that the primary addition product is a A -pyrazoline (2) which rearranges spontaneously to the conjugated A -pyrazoline (3). 

Due to the high reactivity of sulfonium ylide 2 for a,P-unsaturated ketone substrates, it normally undergoes methylene transfer to the carbonyl to give the corresponding epoxides. However, cyclopropanation did take place when 1,1-diphenylethylene and ethyl cinnamate were treated with 2 to furnish cyclopropanes 53 and 54, respectively. 

In Corey and Chaykovsky s initial investigation, a cyclic ylide 79 was observed from the reaction of ethyl cinnamate with ylide 1 in addition to 32% of cyclopropane 53. In a similar fashion, an intermolecular cycloaddition between 2-acyl-3,3-bis(methylthio)acrylnitrile 80 and 1 furnished 1-methylthiabenzene 1-oxide 81. Similar cases are found in transformations of ynone 82 to 1-arylthiabenzene 1-oxide 83 and N-cyanoimidate 84 to adduct ylide 85, which was subsequently transformed to 1-methyl-lX -4-thiazin-l-oxide 86. ... 

To a solution of m-ethyl cinnamate (44, 352 mg, 85% pure, 1.70 mmol) and 4-phenylpyridine-A-oxide (85.5 mg, 29 mol%) in 1,2-dichloromethane (4.0 mL) was added catalyst 12 (38.0 mg, 3.5 mol%). The resulting brown solution was cooled to 4°C and then combined with 4.0 mL (8.9 mmol) of pre-cooled bleach solution. The two-phase mixture was stirred for 12 h at 4°C. The reaction mixture was diluted with methyl-t-butyl ether (40 mL) and the organic phase separated, washed with water (2 x 40 mL), brine (40 mL), and then dried over Na2S04. The drying agent was removed by filtration the mother liquors concentrated under reduce pressure. The resulting residue was purified by flash chromatography (silica gel, pet ether/ether = 87 13 v/v) to afford a fraction enriched in cis-epoxide (45, cis/trans . 96 4, 215 mg) and a fraction enriched in trans-epoxide cis/trans 13 87, 54 mg). The combined yield of pure epoxides was 83%. ee of the cis-epoxide was determined to be 92% and the trans-epoxide to be 65%. 

Ethylene oxide (2.5 ml, 0.05 mole) is condensed in a 50-ml round-bottom flask containing 5 ml of methylene chloride by introducing the gas via a tube into the ice-cooled flask. To the cooled flask are added triphenylphosphine (6.6 g, 0.025 mole), benzaldehyde (2.6 g, 0.025 mole), and ethyl bromoacetate (4.2 g, 0.025 mole). The flask is closed with a drying tube, brought to room temperature, and allowed to stand overnight. Fractional distillation of the solution then yields 2-bromoethanol, bp 55717 mm followed by the desired ethyl cinnamate, bp 142-144717 mm (27171 atm) in about 90% yield. The residue consists of triphenylphosphine oxide, mp 150°. 

The combination of CsF with Si(OMe)4 58 is an efficient catalyst for Michael additions, e.g. of tetralone 130 to methacrylamide, followed hy cyclization of the addition product to the cyclic enamide 131 in 94% yield [67]. Likewise, addition of the lactone 132 to methyl cinnamate affords, after subsequent cyclization with tri-fluoroacetic acid, the lactam 133 in 58% yield [68] whereas < -valerolactam 134, with ethyl acrylate in the presence of Si(OEt)4 59/CsF, gives 135 in 98% yield [69]. Whereas 10mol% of CsF are often sufficient, equivalent amounts of Si(OEt)4 59 seem to be necessary for preparation of 135 [69] (Scheme 3.11). 

Ethyl cinnamate[7] To 2.96 g (20.0 mmol) of cinnamic acid in 25 mL of anhydrous THF 3.24 g (20.0 mmol) of CDI was added. When C02 evolution had ceased, 5 mL of ethanol was added and the mixture was refluxed for 30 min. After concentration in a rotary evaporator the residue was taken up in 100 mL of diethylether and extracted three times each with 50 mL of water. After drying of the ethereal solution and concentration in vacuo the residue was distilled to give ethyl cinnamate (b.p. 145-147 °C/17 mm) in 80% yield. 

Formation of mixtures of the above type, which is common with internal olefins, do not occur with many functionalized alkenes. Thus, tertiary cinnamates and cinnamides undergo cycloadditions with benzonitrile oxides to give the 5-Ph and 4-Ph regioisomers in a 25-30 75-70 ratio. This result is in contrast to that obtained when methyl cinnamate was used as the dipolarophile (177). 1,3-Dipolar cycloaddition of nitrile oxides to ethyl o -hydroxycinnamate proceeds regiose-lectively to afford the corresponding ethyl fra s-3-aryl-4,5-dihydro-5-(2-hydro-xyphenyl)-4-isoxazolecarboxylates 36 (178). Reaction of 4-[( )-(2-ethoxycarbo-nylvinyl)] coumarin with acetonitrile oxide gives 37 (R = Me) and 38 in 73% and 3% yields, respectively, while reaction of the same dipolarophile with 4-methoxy-benzonitrile oxide affords only 37 (R = 4-MeOCr>H4) (85%) (179). 

Metal-catalyzed cross-couplings are key transformations for carbon-carbon bond formation. The applicability of continuous-flow systems to this important reaction type has been shown by a Heck reaction carried out in a stainless steel microreactor system (Snyder et al. 2005). A solution of phenyliodide 5 and ethyl acrylate 6 was passed through a solid-phase cartridge reactor loaded with 10% palladium on charcoal (Scheme 2). The process was conducted with a residence time of 30 min at 130°C, giving the desired ethyl cinnamate 7 in 95% isolated yield. The batch process resulted in 100% conversion after 30 min at 140°C using a preconditioned catalyst. 

In one case, namely the interaction of phenylbiguanide and ethyl cinnamate, the product is reported 642) to be a pyrimidine (LXXXVII). 

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