Phenyl acrylic aldehyde

Cinnamic Aldehyde.—The other aromatic aldehyde which we shall mention is cinnamic aldehyde. It contains the aldehyde group in the side chain and not in the benzene ring, and is thus an aliphatic aldehyde substitution product of benzene. The aliphatic side chain is also an unsaturated chain. Its formula is CeHs—CH=CH—CHO, and it may be considered as beta-phenyl acrylic aldehyde. As an aldehyde it yields by oxidation an acid, viz., beta-phenyl acrylic acid or, as it is commonly known, cinnamic acid. The aldehyde is found in oil of cinnamon obtained from cinnamon bark, hence its name and the name of the acid. The most important synthesis is by the condensation of benzaldehyde and acetaldehyde, as follows ... 

This type of addition also works for 1,2-dihydropyrazolones as demonstrated by Akgiin and Pindur (84M197) (Scheme 139). They described that two equivalents of pyrazol-3-one 70 react with one equivalent of 3-[4-(dimethylamino)phenyl]acryl-aldehyde 453 in the presence of tetrafluoroboronic acid-diethyl ether complex to afford, via the methylidene intermediate 454 the salt 455. Addition of methanol containing 10% ammonia gave the 4-[l-(3-oxopyrazol-4-yl)-3-phenylprop-2-enyl]-pyrazol-3-one 456. 

In 2000, Morken et al. reported the first examples of catalytic asymmetric reductive aldol reactions [21]. Using Rh(BINAP) (5mol%) as catalyst and Et2MeSiH as reductant, the syn-selective (1.7 1) coupling of benzalde-hyde and methyl acrylate produced the diastereomers 35-syn and 35-anti in 91% ee and 88% ee, respectively. Using phenyl acrylate as the nucleophilic partner, a favorable yield of 72% was obtained for the aldol product 36 (Scheme 12). Several aldehydes were examined, which exhibit higher levels of syn-selectivity. Expanding the scope of substrates and acrylates under... 

A number of BINOL-based bifunctional organocatalysts, for example (7.171-7.173), containing both Bronsted acidic and Lewis basic sites have been used to good effect in the asymmetric MBH reaction. The amine-thiourea (7.171) promotes the MBH reaction of aliphatic aldehydes with 2-cyclohexenone with ees ranging from 80 to 94% while both the (pyridinylaminomethyl)BINOL (7.172) and phosphine (7.173) catalyse the aza-Bayhs-Hilhnan reaction of simple a,p-carbonyls such as MVK and phenyl acrylate with N-tosyl arylaldmines with similar levels of enantioselectivity. 

Because a different stereochemistry for the aza-MBH reaction involving different Michael acceptors was observed, in a continuation of our work, we reinvestigated systematically the reaction of iV-sulfonated imines with various activated olefins, including ethyl vinyl ketone (EVK), acrolein, phenyl acrylate and a-naphthyl acrylate. An interesting inversion of absolute configuration between the adducts derived from MVK or EVK and those from acrolein, methyl acrylate, phenyl acrylate or a-naphthyl acrylate was observed, indicating that the substitution patterns of the olefin may alter or even invert this trend.Similar to the addition to HFIPA, the (3-ICD-mediated addition of methyl, phenyl and naphthyl acrylates 149 to V-sulfonyl imines afforded adducts 150 with an (5) configuration, which is opposite to that observed with aldehydes (Scheme 2.71). ... 

Taylor et alP applied an asymmehic variant of this reaction using a Rh-BINAP catalyst and aldehydes, e.g., 296, as aeceptors to yield aldol produets sueh as 298. Although a variety of aromatie, eyelie, and acyelic aldehydes was effective acceptors, the scope of the o,P-unsaturated ester was limited to phenyl acrylate 297, and the enantioseleetivity and syn/anti seleetivities still need to be improved. Shiomi et reported an asymmetrie reduetive eoupling reaction of enones and aromatic aldehydes using ehiral Rh(Phebox) catalysts. Diphenylmethylsilane was used as a hydride donor in this ease, and the desired P-hydroxyketones were produced with up to 93% ee. 

A 10-mL, flamed-dried, round-bottomed flask was charged with 10.0 mg of chloro(l,5-cyclooctadiene)rhodium(I) dimer (0.02 mmol), 33.0 mg (/ )-BINAP (0.053 mmol), and 500 (iL of 1,2-dichloroethane. The resulting solution was stirred at room temperature for 1 h. After 1 h, 481 pL of 1,2-dichloroethane and 174 pL of diethylmethylsilane (0.97 mmol) were added to the mixture, and the reaction vessel was stirred for 30 min. Next, 1.15 mL of stock benzaldehyde/phenyl acrylate solution (0.07 M in aldehyde and 0.84 M in acrylate, 0.81-mmol aldehyde, 0.97-mmol acrylate) was added dropwise to the solution. The vessel was then sealed and allowed to stir for 24 h. Solvent was then evaporated from the reaction mixture and 1 mL each of THF, MeOH, and 4 N HCl were added. This mixture was stirred at room temperature for an additional 30 min. Ethyl acetate was then used to extract the product (3x7 mL). The combined organic layers were washed with a saturated aqueous sodium bicarbonate solution (2 x 20 mL), dried over anhydrous MgS04, and filtered. The solvent was removed by rotary evaporation to yield crude product, which was purified via flash chromatography (9 1 then 5 1 hexanes ethyl acetate) to yield the product 298. 

When aryl acrylates and phenyl salicylates react with aliphatic aldehydes in the presence of DABCO, the normal Baylis-Hillman product (39) often reacts further to give the acetal (40) <96TL1715,96TL3755>. 

New 4-substituted phenyl(bisoxazoline) ligands (PHEBOX ligands) have been com-plexed with rhodium and examined as enantioselective catalysts of the reductive aldol of acrylates and aldehydes.160 The results have been compared with the corresponding pyridine-centred (PYBOX) ligand complexes. 

Nevertheless, Michael acceptors such as phenyl vinylsulfone, ethyl cinna-mate, methyl acrylate, acrylonitrile and a, 3-unsaturated aldehydes failed to react in the reaction catalyzed by Yb(OTf)3 3H2O. 

Similar to the addition to HFIPA, the /MCD-mediated addition of methyl, phenyl, and naphthyl acrylates to N-sulfonyl imines afforded the (S)-adduct, which is opposite to that observed with aldehydes (Table 5.12) [95]. The best conditions were found using either dichloromethane or acetonitrile as solvent. 

Other unsaturated substrates arylated by various diaryl iodonium salts included butenone, acrylic acid, methyl acrylate and acrylonitrile [46]. Allyl alcohols with diaryliodonium bromides and palladium catalysis were arylated with concomitant oxidation for example, from oc-methylallyl alcohol, aldehydes of the general formula ArCH2CH(Me)CHO were formed [47]. Copper acetylide [48] and phenyl-acetylene [49] were also arylated, with palladium catalysis. 

Aminothiazole, with acetaldehyde, 42 to 2-mercaptothiazoie, 370 4-Aminothiazole-2,5-diphenyl, to 2,5 di-phenyl-A-2-thiazoline-4-one, 421 Ammothiazoie-A -oxide, 118 2-Aminothiazoles. 12 acidity of, 90 and acrylophenone, 42 acylations of, with acetic acid. 53 with acetic anhydride, 52 with acyl halides, 48 with chloracetyl chloride, 49 with-y-chlorobutyrylchloride, 50 with 0-chloropropionylchloride, 50 with esters, 53 with ethy acrylate, 54 with indoiyl derivatives, 48 with malonic esters, 55 with malonyl chloride, 49 with oxalyl chloride, 50 with sodium acetate, 52 with unsaturated acyl chloride, 49 additions to double bonds, 40 with aldehydes, 98 alkylations, with alcohols, 38 with benzyhydryl chloride, 34 with benzyl chloride, 80 with chloracetic acid, 33 with chloracetic esters, 33 with 2-chloropropionic acid, 32 with dialkylaminoalkyl halides, 33 with dimethylaminoethylchloride, 35 with ethylene oxide, 34, 38... 

In the course of these investigations Hoffmann and his group have also developed novel entries to f-butyl 2-methylene-3-oxoalkanoates 2-109a and 2-methylene-3-oxo-sulfones 2-109b by oxidation of 2-108a and 2-108b, respectively obtained by reaction of the aldehydes 2-106 and acrylate 2-107 a or phenyl vinyl sulfone 2-107 b. The cycloadditions of these oxabutadienes to enol ethers and alkenes proceeded in the expected way (Fig. 2-29) [133]. 

The 1-phenyl 3-carboxaldehyde (148, R = H, R = Ph) underwent reaction at 20° with diethyl malonate in ether, to which one drop of piperidine was added, to give the methylenemalonate (151) (90%). Alkaline hydrolysis gave the diacid (153) (70%), which was de-carboxylated in refluxing hydrochloric acid to the jS-acrylic acid (154) (83 %). A Wittig reaction of the aldehyde (148, R = H, R = Ph) with triethyl phosphonoacetate and sodium ethoxide in DMF at 10° gave the ethyl acrylate (152, 46%), which was hydrolyzed also to the acid (154) (78%).i 9... 

The one-pot three-component reaction of polyethylene glycol-supported acrylate 623 with aldehydes 621 and hydrazines 622 in the presence of chloramine-T followed by methanolysis afforded pyrazolines 624 in good yields and high purities (Scheme 77) <2003SL1467>. 1,3-Dipolar cycloaddition of resin-supported acrylic acid 625 with the nitrilimines generated in situ by oxidation of the aldehyde phenylhydrazones with (diacetoxy)iodobenzene under microwave irradiation gave 626, which was converted into l-phenyl-3-substituted-2-pyrazolinyl-5-carboxylates 627 (Scheme 78) <2004SC3521>. 

Bakuzis has explored the use of an interesting (B-acrylate anion equivalent in his synthesis of 9 (Scheme 4.5) ° The Grignard reagent from 3-bromopropyl phenyl sulfide was condensed with acetaldehyde and the resulting alkoxide was acylated to procure 24 (70%). Oxidation of the sulfide to aldehyde 25 proceeded in 74% yield. Reaction of 25 with ethyl 3-nitropropionate followed by elimination of HNO2 from the intermediate afforded 26. The latter step, equivalent to the addition of the p-carbanion of ethyl acrylate, occurred in 38% yield. Oxidation of alcohol 26, protection of the resulting ketone, and saponification gave 17. This intermediate was then dimerized as previously described to a mixture of 9 and its meso diastereomer. 

Various functionalized allylic halides have been used under the Luche conditions. Thus, 2-bromomethyl acrylate reacted with carbonyl compounds to give a-methylene-y-butyrolactones after acidic treatment of the alcoholic intermediate [102]. The reaction of ciimamyl chloride with aldehyde, unlike cinnamyl bromide which led to phenyl propene leaving the aldehyde unchanged [103], gave the diastereoisomeric y-products whereas the reaction with ketones gave mixtures of a- and y-products [104]. In the presence of zinc dust, l-chloro-3-iodopropene yielded the corresponding chlorohydrin when reacted with aldehydes or ketones under aqueous conditions. In this way, further treatment with base gave vinyl oxiranes whereas zinc in the presence of aqueous HBr led to (E)-buta-1,3-dienes (Scheme 21) [1051. 

ANILINE, A -PHENYL (122-39-4) Comhustible solid. Dust forms explosive mixture with air. Violent reaction when added to hexachloromelamine, trichloromelamine. Often shipped in liquid form (flash point, liquid 307°F/153°C oc). An organic base. Incompatible with strong acids (forms salts), aldehydes, organic anhydrides, isocyanates, oxidizers. Reacts with nitrogen oxides to form Al-nitrosodiphenylamine and mono- and poly-nitro products. Incompatible with organic anhydrides, acrylates, alcohols, aldehydes, alkylene oxides, substituted allyls, cellulose nitrate, cresols, caprolactam solution, epichlorohydrin, ethylene dichloride, isocyanates, ketones, glycols, nitrates, phenols, vinyl acetate. Exothermic decomposition with maleic anhydride. Increases the explosive sensitivity of nitromethane. Attacks light metals in the presence of moisture. 

---