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The 1,3-dipolar cycloaddition reaction of azomethine ylides generated in situ by isatin and L-proline to acrylonitrile and methyl acrylate in water affords a series of spirooxindolo pyrrolizidines in good yields.

A general method for accessing 5-alkyl-5-aryl-γ-lactams has been developed using readily available aryl bromides, nitroalkanes, and methyl acrylate as the starting materials. The palladium-catalyzed arylation of nitroalkanes gave the 1-aryl-substituted nitroalkanes, which underwent the DBU-mediated Michael addition with methyl acrylate at room temperature to afford the methyl 4-aryl-4-nitroalkanoates. The latter were then subjected to the nitro reduction using NaBH4–NiCl2·6H2O in MeOH at 0 °C to furnish, after treatment with aqueous K2CO3 at room temperature, the 5-alkyl-5-aryl-γ-lactams in good to excellent overall yields. Selected examples of N-alkylation of the γ-lactams were also illustrated.

Under optimized conditions, the title process affords the coupling products in good yields.

We have found that in the in the Baylis-Hillman reactions of N-arylidenediphenylphosphinamides 1 with methyl vinyl ketone (MVK), methyl acrylate or acrylonitrile, the lewis base and solvent can significantly affect the reaction rate. Using PPh^3 as Lewis base in the reaction of 1 with MVK in DMF, THF or MeCN, the normal Baylis-Hillman adduct 2 was formed in very high yield, In the Baylis-Hillman reaction of 1 with methyl acrylate, the Lewis base Ph2PMe must be used in order to get a high yield of te Baylis-Hillman adduct 3. On the other hand, for the reaction of N-aryldenediphenylphosphinamides 1 with acrylonitrile, DABCO is the best Lewis base giving the corresponding Baylis-Hillman adducts 4 in high yields.

Mizoroki—Heck cross-couplings of aryl iodides (I) in the presence of a Pd-catalyst supported on a rasta resin bearing diphenylphosphanyl ligands are reported.

We describe an unusual [2+2+2] MIMIRC reaction between a lithium dienolate 6 and methyl acrylate. The more classical double Michael addition cyclisation provides an efficient entry towards key intermediate 5 for 2-isocyanopupukeanane 1 synthesis.

A study was carried out on the effect of pressure up to 1400 MPa on the Diels-Alder reaction between furan and methyl acrylate at 20‡C. At atmospheric pressure, the reaction proceeds with 20% yield after two months, while it proceeds at 1400 MPa with 70% yield after 2.5 h. The observed volumetric activation effect (−δVp≠) of this reaction decreases relatively slightly with increasing pressure and its value at 0.1 MPa (20 cm3/mole) is markedly less than the change in volume upon reaction (−δV0=29 cm3/mole). The ratio of the endo and exo isomers formed is 2.6 and is independent of the pressure.

The reactins of o-bromobenzaldehydes with methyl acrylate under Heck conditions and with phase-transfer catalysis to yield significant amounts of doubly substituted deformylated products 1A-E in addition to the expeted o-formyl cinnamates 2A-E are reported. X-ray crystallography of one such product (4) established that the bromine was replaced by a propionate and the formyl group by an acrylate residue. Employment of deuterium-labeled substrates showed that the hydrogen atom of the formyl group of the substrate was transferred intramolecularly and regiospecifically to the benzylic carbon of the propionate substituent of the product. A tentative hypothesis is advanced to explain these and other experimental findings

Variously N-protected α-aminoaldehydes exhibit reasonable diastereoselectivity in the Baylis-Hillman coupling1 with methyl acrylate to provide either primarily syn or anti α-methylene-β-hydroxy-γ-amino esters.

The asymmetric Diels–Alder reaction of cyclopentadiene and methyl acrylate has been effected with high enantioselectivity under the influences of catalytic amounts of chiral organoaluminum reagents.

Chalcones [( E )-1,3-diarylprop-2-en-1-ones] react with benzyltetracarbonylmanganese under reflux in petroleum spirit to give two types of cyclomanganation products. The first, involving metallation at the alkenyl β-carbon of the enone, are derivatives of [[1-phenyl-2-phenylcarbonyl- κO ]ethenyl- κC 1 ]tetracarbonylmanganese, while the second type, manganated at the aryl ring ortho -carbon, are derivatives of [2-[3-phenylprop-2-en-1-onyl- κO ]phenyl- κC 1 ]tetracarbonylmanganese. In general, more “alkene-manganated” than “ring-manganated” product is formed, with the ratio influenced significantly by certain substituents, e.g. a 4-CF 3 substituent on the phenyl ring at C3 of the enone strongly promotes “alkene-manganation”. In some cases there are minor by-products derived from coupling of two chalcone molecules after initial cyclomanganation. The crystal structures are reported for two such products, [2-((1 S ∗ , 2 R ∗ , 3 S ∗ )-1- hydroxy -1-((E)-2-(2- trifluoromethylphenyl)ethenyl )-3-(2- trifluoromethylphenyl )-6- methoxy -2- indanylcarbonyl -κO)-6- methoxyphenyl -κC 1 ] tetracarbonylmanganese and (1S ∗ , 4S ∗ , 5R ∗ )-5-(4-bromobenzoyl)-1-(4-bromophenyl)-3,4-di-(4-trifluoromethylphenyl)cyclopent-2-en-1-ol. In acetonitrile under reflux, alkene-manganated chalcones react with methyl acrylate (methyl propenoate) to form derivatives of methyl ( E )-4,6-diphenyl-6-oxohex-2-enoate and of 5-(2-methoxycarbonylethyl)-3,5-diphenylfuran-2(5H)-one. The latter butenolides are not formed when the reactions are carried out in carbon tetrachloride, only the former α, β-unsaturated esters. By contrast, in a few reactions studied, acrolein (propenal) and methyl vinyl ketone (but-3-en-2-one) give only the butenolide products when treated with alkene-manganated chalcones in refluxing acetonitrile. An exception is the reaction of methyl vinyl ketone with [[1-(3,4,5-trimethoxyphenyl)-2-(4-chlorophenylcarbonyl- κO )]ethenyl- κC 1 ]tetracarbonylmanganese to form the cyclized product 5-acetyl-1-(4-chlorophenyl)-3-(3,4,5-trimethoxyphenyl)cyclopent-2-en-1-ol.

Planar chiral tricarbonylchromium complexes of ortho-substituted benzaldehydes or acetophenones were coupled with methyl acrylate in the presence of samarium(II) iodide to give stereoselectively γ-butyrolactones in good yields.

The variations in the endo- and exo-stereoselectivities for the reaction of cyclopentadiene (CP) with methyl acrylate (MA) have been investigated in salt−solvent reaction media (SSRM) at different concentrations of salts. The SSRM employed in the reaction include aqueous solutions of LiCl, NaCl, NaBr, CaCl2, guanidinium chloride, and LiClO4. The endo/exo (N/X) ratios have been noted to be sensitive to the ionic concentrations. Salts such as LiCl, NaCl, NaBr, and CaCl2 enhance the N/X ratios, while the solutions of guanidinium chloride and LiClO4 decrease them. The results have been analyzed in light of the salting-out and -in coefficients. The scaled particle theory has also been employed to calculate the contributions from the cavitation and solvation effects. The correlations of the N/X ratios with the surface tension of the SSRM are presented, which bring out clearly the impact of the surface tension of reaction media on the stereoselectivities of the above reaction. An attempt has also been made to in...

In basic medium, dimethyl 3,3‘-dithiopropionate generates methyl acrylate, which serves in situ as a source of propionate moiety. This property was applied to the alkylation of indoles and other nitrogen heterocycles leading to a series of 3-(heteroaryl-substituted) propionates. A mechanistic rationale for the generation of acrylate is presented along with supportive experimental data.

Triphenylantimony dicarboxylates Ph3Sb(OAc)2 and Ph3Sb(O2CEt)2 are efficient C-phenylating agents for methyl acrylate. In the presence of the Pd(OAc)2, Li2PdCl4 or Pd2(dba)3(CHCl3) catalysts in MeCN at 50 °C, methyl cinnamate forms in 70—150% yield with respect to SbV. Copper(ii) salts do not increase the reaction yield.

In situ prepared iminium salts are very effective electrophiles in Baylis–Hillman reactions and react with methyl acrylate in the presence of a catalytic amount of a tertiary amine at ambient temperatures to afford the corresponding Baylis–Hillman adducts. The product undergoes conjugated addition with (trimethylsilyl)dialkylamines to give the diamine 5 in good yields.

The effects of various catalysts, the solvent system, and the temperature on the efficiency and chemoselectivity of reactions of a series of chromone-3-carbaldehydes with acrylonitrile and methyl acrylate are discussed.

A protocol for the ruthenium-catalyzed cross-metathesis of fatty-esters from plant oils and optimized experimental parameters for the individual substrates are presented.

TMSOTf-mediated reactions of 2-aryl-1-(1-phenylcyclopropyl)ethanones 1 with allenic esters afford a novel method for the synthesis of 6-methyl-3a,7-diaryl-3,3a-dihydro-2H-benzofuran-4-one derivatives 2 in moderate yields. In addition, we also found that TMSOTf-mediated reactions of 1-cyclopropyl-2-arylethanones with ethyl acetoacetate can provide the corresponding 2,3-dihydrobenzofuran-4-ol and dihydrofuro[2,3-h]chromen-2-one in moderate yields via a sequential reaction involving a nucleophilic ring-opening reaction of the cyclopropane by H2O, one intermolecular aldol type reaction and two intramolecular aldol type reactions, a cyclic transesterification, dehydration, and aromatization. Moreover, by using methyl acrylate to replace allenic ester, the corresponding 7-aryl-3,5,6,7-tetrahydro-2H-benzofuran-4-one and 5-aryl-3,5,6,7-tetrahydro-2 H-benzofuran-4-one can be formed in moderate to high yields in the presence of Bi(OTf)2Cl. Plausible reaction mechanisms have also been provided on the basis of control experiments.

The title reactions allow easy and stereoselective access to highly substituted isoindole and indan derivatives, tricyclic ring systems of type (VI), and other fused cyclohexenes.

The reaction tolerates a wide range of aromatic, heteroaromatic, olefinic, aliphatic and isomerizable aliphatic substituents.

The cross-metathesis of fatty acid esters derived from plant oils as renewable raw materials with methyl acrylate was studied, revealing high conversions for the synthesis of α,ω-dicarboxylic acid esters, depending on the choice of catalyst. A series of unsaturated α,ω-diesters (1,8-, 1,11-, 1,12-, 1,15-, and 1,20-), as well as unsaturated α-esters, was thus prepared and fully characterized. The obtained results can significantly contribute to a sustainable supply of monomers for polyester and polyamide synthesis, as well as for detergents.

Aza-Morita-Baylis-Hillman reactions of N-(benzylidene)polyfluoroanilines 1 with methyl acrylate or acrylonitrile were studied. It was found that Lewis base, solvent and reaction temperature can significantly affect the reaction. Using 3-hydroxyquinuclidine (3-HQD) as a Lewis base in the reactions of 1 with methyl acrylate in DMF, the normal aza-Morita-Baylis-Hillman adducts 3 were formed in moderate to excellent yields. For the reactions of 1 with acrylonitrile, 1,4-diazabicyclo[2.2.2]octane (DABCO) is the best Lewis base giving the corresponding aza-Morita-Baylis-Hillman adducts 4 as the sole product in good to moderate yield. However, upon treatment of 1 with acrolein 2c, the corresponding reaction did not occur even in the presence of a variety of catalysts.

A new PPh3-catalyzed synthesis of alkyl 2-[aryl(tosylimino)methyl]acrylates from propiolate and N-tosylimine has been developed. Deuterium-labelling experiments show that the reaction mechanism involves several hydrogen-transfer processes, which are not the turnover-limiting step and strongly rely on the nature of the reaction media. The stable phosphonium–enamine zwitterion, which was proven to play an important role in the catalytic cycle, has been isolated and characterised by X-ray analysis.

Heck vinylation reactions of different anilines were performed with vinylacetate by using palladium chloride and copper nitrate intercalated montmorillonite K10 clay as catalyst. The substituted methylcinnamates were obtained in good yields without simultaneous side reaction to stilbenes.

N,N-Dibenzyltrifluoroacetamide was formed in good yield by treating benzyl diphenylphosphinite with N-benzyltrifluoroacetamide in the presence of easily available methyl acrylate under mild conditi...

International audience; A good choice: A new catalytic method was found for the construction of stereogenic quaternary carbon centers through a copper-catalyzed domino conjugated reduction/aldol reaction of methyl acrylate with various alkyl aryl ketones. The proper choice of the chiral diphosphine ligand leads to high chemo-, diastereo-, and enantioselectivity.

Catalytic C-phenylation of methyl acrylate to methyl cinnamate with the Ph4SbX complexes (X = F, Cl, Br, OH, OAc, O2CEt) in the presence of the palladium compounds PdCl2, Pd(OAc)2, Pd2(dba)3, Pd(Ph3P)2Cl2, and Pd(dppf)Cl2 (dba is dibenzylideneacetone and dppf is bis(diphenylphosphinoferrocene)) was studied in organic solvents (MeCN, THF, DMF, MeOH, and AcOH). The highest yield of methyl cinnamate (73% based on the starting organometallic compound) was obtained for the Ph4SbCl—PdCl2 (1 : 0.04) system in acetonitrile.

Benzindolizidine systems are generated in moderate yields by a hexabutylditin mediated consecutive radical addition, cyclization, oxidation process from 1-(2-iodoethyl)indoles and methyl acrylate.