Methyl cinnamate, preparation

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). 

The variety of educts and products of the higher MCRs is illustrated here. Product 72 (Scheme 1.18) is formed from the five functional groups of lysine, benzaldehyde, and tert-butylisocyanide. The synthesis of 73 is achieved with hydrazine, furanaldehyde, malonic acid, and the isocyano methylester of acetic acid, compound 74 results from the reaction of benzylamine, 5-methyl-2-furanaldehyde, maleic acid mono-ethylester, and benzylisocyanide. ° Zhu et al. prepared a variety of related products, such as, 75, from (9-amino-methyl cinnamate, heptanal, and a-isocyano a-benzyl acetamides. 

Methyl cinnamate is a colorless crystalline solid mp 36.5 °C) with a fruity, sweet-balsamic odor. In addition to the common esterification methods, it can be prepared by Claisen condensation of benzaldehyde and methyl acetate in the presence of sodium. Methyl cinnamate is used in soap perfumes, as well as in blossom and oriental perfumes, and is sometimes added to aromas. 

Ethyl cinnamate may also be prepared by the esterification of cinnamic acid (cf. methyl cinnamate, Expt 6.163). The pure compound boils at 127°C/6mmHg. 

Dimerization.- A reinvestigation of the dimerization of (124) in the solid phase has identified (125) as the product. The irradiation of microcrystalline methyl cinnamate (126) affords a complex mixture of products. However, the preparation of crystalline complexes of this ester with boron trifluoride or stannic chloride followed by irradiation affords high yields of the a-truxillate dimer (127). Ethyl cinnamate also forms complexes with the same reagents but irradiation of these crystalline complexes affords a mixture of dimers in low... 

Pans-2-Iodocyclohexyl acetate can be isolated in essentially quantitative yield from the reaction of thallium(I) acetate, iodine, and cyclohexene in a 1 1 1 molar ratio in refluxing chloroform. lodo acetates from a representative series of alkenes including cyclohexene have been similarly prepared in 80-98% yield in glacial acetic acid which was not dried as described in this procedure. The corresponding iodo benzoates are obtained in comparable yields from reaction with thallium(I) benzoate and iodine in benzene. The deactivated olefin methyl cinnamate did not react under these conditions, and o-allylphenol underwent ring iodination to... 

As shown in Scheme 3, (Z)-enolate (57), prepared by conjugate addition of lithium bis(phenyldi-methylsilyl)cuprate to methyl crotonate or methyl cinnamate, reacts with acetaldehyde or benzaldehyde to give a mixture of two diastereomeric aldols, (58) and (59), with excellent diastereomeric excess favoring (58) (ratios of 85 15 to 94 6). On the other hand, deprotonation of ester (60) by LDA provides the ( )-enolate (61), which reacts with the same two aldehydes to give the aldol (59) as the major product... 

The A A reaction has been used in the preparation of the paclitaxel 44 side-chain 47.28 The structure activity relationship (SAR) associated with the anti-cancer activity of the scaffold embedded in this substituent is wellknown. Starting with the commercially available methyl cinnamate 45, on a one-third mole scale, the advanced intermediate 46 could be prepared in one step with essentially no workup. The ready access to 46 enabled the preparation of 47 which could be used in the semi-synthesis of 44. 

Methyl cinnamate (I) from Eastman Organic Chemicals was recrystallized from acetone-water solution and then sublimed. Dimethyl itaconate (V) was from Chas. Pfizer Company and purified by sublimation and preparative gas... 

Biemer et al. reported the enantioselective behaviors of a Pd catalysts supported on specially prepared silica gels, which have been precipitated from Na silicate wiA HCl in the presence of optically active alkaloids sulfates of quinine (Q), quinidine (Qd ), cinchonine (Cn), or cinchonidine (Cnd). These catalysts proved to be active in the asymmetric hydrogenation of 2-methyl-cinnamic acid (Scheme 3.1.) . 

As an alternative functional group to an epoxide, cyclic sulfates and sulfites have also been used as intermediates to prepare the taxol side chain. Thus, asymmetric dihydroxylation of cis methyl cinnamate using AD-mix (3 gave the diol 7.2.12, which was converted to the cyclic sulfate... 

For this reason, copolymers 286 and 287 having a polar polymer structure were prepared by radical copolymerization of monomer 283 with methylmethacrylate or 2-hydroxyethyl methaciylate in presence of AIBN (Scheme 114). Indeed, these polymers seemed to be more compatible with the liquid reaction medium because both yield and enantioselectivity were higher widi the two NMO/acetone/H20 and K3Fe(CN)e/i-Bu0H/H20 systems in the AD of trans methyl cinnamate. 

The reaction is completed in less than 2h, except for methyl cinnamate and 2-nitropropane, which require much longer times. Without sonication, additions are slow. Even if restricted to P-monosubstituted esters, this method has a preparative value. 

The free-radical-initiated copolymerization of trans-stilbene with MA was recently studied as a route to poly(methyl cinnamate). Alternating copolymers were prepared with specific viscosities, measured at 30°C in 0.5 NaOH (0.2g/100ml), as high as 1.40 dl/g. Esterification with methyl alcohol gave head-to-head (H-H) poly(methyl cinnamate). Even though H-H poly(methyl cinnamate) Tg was higher than head-to-tail (H-T) poly(methyl cinnamate), the H-H material had poorer stability than the H-T material. " """ ... 

Pyrroles.—Formation. Toluene-p-sulphonyl-alkyl isocyanides react with electron-poor olefins to furnish pyrroles thus compound (279) and methyl cinnamate give the ester (280). Treatment of the isocyano-ester MeCH=C(NC)C02Et with Li" CH(NC)C02Et affords the pyrrole derivative (281). A series of amino-nitriles (282 R = alkyl, Ph, etc.) has been prepared by the action of... 

As with poly(vinyl alcohol), poly(vinyl cinnamate) is prepared by chemical modification of another polymer rather than from monomer . One process is to treat poly(vinyl alcohol) with cinnamoyl chloride and pyridine but this is rather slow. Use of the Schotten Baumann reaction will, however, allow esterification to proceed at a reasonable rate. In one example poly(vinyl alcohol) of degree of polymerisation 1400 and degree of saponification of 95% was dissolved in water. To this was added a concentrated potassium hydroxide solution and then cinnamoyl chloride in methyl ethyl ketone. The product was, in effect a vinyl alcohol-vinyl cinnamate copolymer Figure 14.8)... 

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