Methyl acrylate 750 Subject

The cycloadducts formed from the Diels-Alder reaction of 3-amino-5-chloro-2(17/)-pyrazinones with methyl acrylate in toluene are subject to two alternative modes of ring transformation yielding either methyl 6-cyano-l,2-dihydro-2-oxo-4-pyridinecarboxylates or the corresponding 3-amino-6-cyano-l,2,5,6-tetrahydro-2-oxo-4-pyridinecarboxylates. From the latter compounds, 3-amino-2-pyridones can be generated through subsequent loss of HCN <96 JOC(61)304>. Synthesis of 3-spirocyclopropane-4-pyridone and furo[2,3-c]pyridine derivatives can be achieved by the thermal rearrangement of nitrone and nitrile oxide cycloadducts of bicyclopropylidene <96JCX (61)1665>. 

Methyl acrylate (94.7 mg, 1.1 mmol) is added dropwise at room temperature to a suspension of morphinolone 132 (253 mg, 1 mmol), CsF (132 mg, 1 mmol), and Si(OMe)4 58 (150 pL) under argon. After stirring for 1 h the reaction mixture is subjected to flash chromatography on silica gel (eluent petroleum ether-ethyl acetate, 8 2) to afford a 1 1 mixture of isomers 133 (82% yield) as a colorless oil [68] (Scheme 3.18). 

The vinyl triflate of Komfeld s ketone has been subjected to Heck reactions with methyl acrylate, methyl methacrylate, and methyl 3-(Af-rerf-butoxycarbonyl-lV-methyl)amino-2-methylenepropionate leading to a formal synthesis of lysergic acid [259]. A similar Heck reaction between l-(phenylsulfonyl)indol-5-yl triflate and dehydroalanine methyl ester was described by this research group [260]. Chloropyrazines undergo Heck couplings with both indole and 1-tosylindole, and these reactions are discussed in the pyrazine Chapter [261], Rajeswaran and Srinivasan described an interesting arylation of bromomethyl indole 229 with arenes [262]. Subsequent desulfurization and hydrolysis furnishes 2-arylmethylindoles 230. Bis-indole 231 was also prepared in this study. 

In the process of developing the Stetter reaction in ionic liquids, Gree and coworkers applied their methodology to the synthesis of haloperidol (Scheme 25) [101], A variety of aromatic aldehydes react with methyl acrylate 160 when butyl-methylimidazolium tetrafluoroborate [bmim][BF ] is used as solvent. In the synthesis of haloperidol, electron-deficient aldehyde 153 was subjected to standard reaction conditions with 160 to provide 161 in good yield. 

Cyclization is a key reaction in the production of carbon fibers from polyacrylonitrile (PAN) (acrylic fiber see Sec. 3-14d-2). The acrylic fiber used for this purpose usually contains no more than 0.5-5% comonomer (usually methyl acrylate or methacrylate or methacrylic acid). Highly drawn (oriented) fibers are subjected to successive thermal treatments—initially 200-300°C in air followed by 1200-2000°C in nitrogen [Riggs, 1985]. PAN undergoes cyclization via polymerization through the nitrile groups to form a ladder structure (XXVII). Further reaction results in aromatization to the polyquinizarine structure (XXVIII)... 

The pioneer work on this subject using simple 1-azadienes is due to Ghosez et al. (82TL3261 85JHC69) they succeeded in reacting 1-azadienes as 47r-electron components in Diels-Alder cycloadditions. Thus, l-dimethylamino-3-methyl-l-azabuta-l,3-diene (a,/3-unsaturated hydrazone) 54 did undergo [4 + 2] cycloaddition to typical electron-poor dienophiles, e.g., methyl acrylate, dimethyl fumarate, acrylonitrile, maleic anhydride, and naphthoquinone, producing pyridine derivatives 55-57 (Scheme 14). 

To a stirred solution of methyl acrylate (0.67 mL, 7.5 mmol) in Cl 12C12 (24.5 mL) was added a 0.75 M MeOBr in CH2C l2 (2.0mL, 1.5 mmol), followed immediately by BF3OEt2 (0.18mL, 1.5mmol). After 5 min the mixture was subjected to H20 workup and the CH2C1, soln was analyzed directly by vapor-phase chromatography. 

Fig (19) Octalin ketal (163) is converted to kete dithioacetal (164) by the cleavage of ketal function and condensation with carbon disulfide and methyl iodide. Subjection of (164) to the action of dimethylsulfonium niethylide and acid hydrolysis leads to the formation of unsaturated lactone (165).lts furan silyl ether derivative is caused to undergo Diets-Atder reaction with methyl acrylate to obtain salicyctic ester (166) which is converted by standard organic reactions toabietane ether (167). It is converted to aiiylic alcohol (168) by epoxidation and elimination. Alcohol (169) obtained from (168) yields orthoamide which undergoes transformation to amide (170). Its conversion to the previously reported intermediate has been achieved by epoxidation, elimination and hydrolysis. 

These examples demonstrate that a selective Heck-Diels-Alder sequence with two different alkenes is only possible either in a stepwise manner, if an alkene reacts much faster in the Heck reaction than in the subsequent cycloaddition so that the 1,3-diene can be isolated, or as a real cascade reaction if one alkene is more reactive and thus selectively reacts as a coupling partner, whereas the other one is a better dienophile. Both concepts have been used by Kollar et al. for the annelation of cyclohexene rings onto the steroidal skeleton 26 (Scheme 4) [28-30]. At 60 °C the cycloaddition was sufficiently suppressed so that the Heck coupling product 29 could be isolated and subsequently subjected to Diels-Alder reactions with different dienophiles. For a domino reaction with both methyl acrylate and dimethyl fumarate (28) present in the reaction mixture, the conditions had to be precisely adjusted so that the mixed products 31 and 32 were formed predominantly along with only small amounts of the products of a twofold reaction of either 27 (R = CC Me) or 28 with 26. These conditions also proved suitable for a cascade reaction of 26 involving allyl alcohol 27 (R = CH2OH) or allyl acetate 27 (R = CH2OAc) and dimethyl fumarate (28). 

Benzindolizidine systems 963 are generated in moderate yields by a hexabutylditin-mediated consecutive radical addition, cyclization, and oxidation process from easily accessible l-(2-iodoethyl)indoles 962 and methyl acrylate, in one step (Scheme 186) <2000TL10181>. l-(2-Iodoethyl)-l//-pyrrole-2-carbaldehyde was also subjected to the tandem radical addition-cyclization process, and the indolizidine derivative 964 was isolated in modest yield as the major product together with a small amount of starting material (Equation 229). 

General procedure, method A was followed using complex 2 (0.828 g, 3.00 mmol) and methyl acrylate (0.54 mL, 6.00 mmol). The residue, after evaporation, was distilled (Kugelrohr, 25-55 °C/0.025 Torr). The distillate was subjected to flash chromatography (silica gel, hexane/EtOAc 9 1). The product in the first fraction (Rj 0.53, hexane/EtOAc 4 1) was identified as methyl tra j-l-methoxy-[l,l -bicyclopropyl]-2-carboxylate (4a 0.155 g, 30%). The product in the second fraction Rj 0.51, hexane/EtOAc 4 1) was identified as methyl 4-cyclopropyl-4-methoxybut-2-enoate (0.047 g, 9%). The product in the third fraction (Rf 0.38, hexane/EtOAc 4 1) was identified as methyl cw-l-methoxy-[l,l -bicyclopropyl]-2-carboxylate (3a 0.166 g, 33%). 

The condensation, using heterogeneous catalysts, of methyl esters of acetic or propionic acids with formaldehyde to form methyl acrylate or methyl methacrylate has been the subject of a number of recent patents. Thus, lead acetate on silica 145), manganese dioxide on silica (146), and Ba-, Ca-, Sr-, and Mg- Decalso derivatives (147) have been effective catalysts for this reaction. 

Other reactions studied by these authors include the thermal dimerization of methyl acrylate and the reaction of benzene with certain alkynes in a Diels-Alder reaction. Supercritical extraction in coal processing may also be classified under this scheme. This subject is reviewed by Williams (1981) it is not included in this chapter. 

The Diels-Alder reaction has been shown to be subject to catalysis by a wide range of solid catalysts (see Chapter 4 for some examples). Acidic mesoporous aluminosilicates can be used to catalyse selective Diels-Alder reactions such as that between cyclopentadiene with methyl acrylate. The zinc-exchanged version of the material is particularly effective and compares well to other more established solid acids such as the ion-exchanged clay Zn2+-K10 as well as homogeneous catalysts such as boron trifluoride (Table 2.7).50... 

An improved synthesis of glutinosone (1) was also accomplished by Masamune and coworkers6 and this was based on procedure developed by Dastur7,8 for the synthesis of sesquiterpenes nootkatone. (Scheme 2) Diels-Alder reaction of 3,6-dihydro-3,5-dimethyl anisole with methyl acrylate in absence of Lewis acids afforded a 1 3 mixture of esters (17) and (18) which were converted to a,(3-unsaturated aldehydes (19) in 77% yield by oxidation with selenium (IV) oxide in dioxane. Wittig reaction of aldehydes under the usual condition yielded the dienes (20) in 63% yield which on being subjected to Grignard reaction with an excess of methyllithium produced tettiary alcohols (21) in quantitative yield. This on treatment with formic acid at room temperature gave bicyclic enone (22) and its formate (23) in 45% and 41% yield respectively. Formates (23) were hydrolyzed to enone (22) in 88% yield. 

The attachment of cymantrene groups to polymers has attracted interest for other reasons. Studies have shown, for example, that adherent, abrasion-resistant coatings are formed on metals when thin films of the Mn-containing polymer are subjected to irradiation with UV light. The polymerization of styrene tricarbonylchromium 47 has also been studied.This species is available from the reaction of styrene with Cr(CO)3(NH3)3. Although the Cr monomer 47 resisted attempts at homopolymerization, co-polymerizations with styrene, methyl acrylate, as well as with 41 to yield bimetallic polymers 48 were possible (Equation (17)). In addition, co-polymerization with vinyl-ferrocene afforded co-polymers of low molecular weight (Mn = ca. 4,000). A variety of other organometallic vinyl momomers 49 has been successfully polymerized to yield polymers 50 that contain pendant Gr, W, and Ir carbonyl moieties (Equation (18)). ... 

For analysis, the crude ACT reaction mixtures were subjected to a standard telomer assay as follows [14, 15]. The tin products were removed by chromatography and treatment with KF. The resulting macrocyclic mixtures were then hydrolyzed under acidic conditions to yield the corresponding acrylic acid telomers. Hydrolysis of the desired n=4 macrocycle is shown in Scheme 8-9. Esterification of the reaction mixture with diazomethane gave the methyl acrylate telomers 26 that were then readily identified by gas chromatography/mass spectrometry. 

To a 1-liter flask equipped with a condenser, an addition funnel, a mechanical stirrer, and a thermowell-thermometer assembly is added 93.2 gm (1.08 mole) of the methyl acrylate and then heated to 32°C. Then 18.0 gm (0.050 mole) of the product of B above dissolved in 58.1 gm methanol is added over a 1.5 hr period. The resulting reaction mixture is kept at 32°C for an additional 5 hr and then allowed to stand at room temperature for 18 hr. Then the reaction mixture (165.7 gm) is subjected to vacuum distillation (2.0 mm Hg at 50°C) in order to remove the excess methyl acrylate and methanol to give 43.1 gm (98.4% yield)... 

The regiochemical and stereochemical courses of the photocycloaddition of A-acylindoles with monosubstituted olefins such as methyl acrylate and vinyl acetate, as well as the possible mechanistic pathways for these reactions, have been the subject of several reports. In one of the earliest examples, the photocycloaddition of 1 -benzoylindole (8) and methyl acrylate (9) produced the compound 10, which was then converted via a short synthetic sequence to a variety of 2a,7b-dihydrocyclobut[h]indole derivatives 11 (Scheme 2). These compounds were in turn converted to the corresponding l//-l-benzazepines 12, through silver ion-catalyzed thermolysis reactions at 100-160°C [14, 15]. 

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