Acrylic Acid Methyl Ester Research Articles

Cycloaddition-Rearrangement Sequence of 2-Amido Substituted Furans as a Method of Synthesizing Hexahydroindolinones.

A convenient synthesis of various substituted hexahydroindolinones has been achieved by an intramolecular Diels-Alder cycloaddition (IMDAF) reaction of 2-amido substituted furans. The initially formed [4 + 2] cycloadduct undergoes nitrogen-assisted ring opening followed by deprotonation of the resulting zwitterion to give the rearranged ketone. The stereochemical outcome of the IMDAF cycloaddition has the sidearm of the tethered alkenyl group oriented syn with respect to the oxygen bridge. The reaction rate and product yield were found to be markedly dependent upon the electronic properties of the alkenyl pi-bond. 2-[2-(tert-Butoxycarbonylfuran-2-yl-amino)ethyl]acrylic acid methyl ester was synthesized from 3-chlorocarbonyl-but-3-enoic acid methyl ester. Thermolysis of the carbomethoxy activated furanamide occurred at 80 degrees C to produce a rearranged hexahydroindolinone. When Me(3)Al or (MeO)(3)Al was used as a Lewis acid to promote the cycloaddition, a rearranged alcohol was obtained. The initially formed [4 + 2] cycloadduct undergoes ring opening in the presence of the Lewis acid, and the resulting aluminum intermediate delivers the substituent group from the same face as the neighboring oxygen to ultimately furnish a rearranged cis-alcohol. In contrast to this result, a mixture of diastereomeric methoxy alcohols was isolated when the IMDAF cycloaddition was carried out in methanol. The major isomer corresponds to the trans-diastereomer that results from trapping of the iminium ion from the less crowded face of the pi-bond.

The use of in situ NMR spectroscopy and parahydrogen as tools for chiral synthesis

1. In situ 1H NMR spectroscopy and using parahydrogen (p-H 2) allows to characterize the stereochemistry of suitable hydrogenation reactions instantaneously. 2. The rhodium(I)-catalyzed homogeneous hydrogenation of the unsaturated racemic alcohols ( R,S)-2-(1-hydroxy-ethyl)-acrylic acid methyl ester ( I) and ( R,S)-2-methoxy-1-phenyl-buta-2,3-dien-1-ol ( II) leads to the formation of different diastereomeric products which can be distinguished unambiguously due to their characteristic polarization multiplets.

Radical terpolymerization of ethylene, methyl acrylate and vinyl acetate under high pressure. Physical properties of the polymers

AbstractPolymerization tests were carried out in a stirred autoclave designed for continuous operation in order to determine the influence of the reaction pressure and temperature and of the acrylic acid methyl ester and vinyl acetate comonomers on the ethylene‐acrylic acid methyl ester‐vinyl acetate terpolymer formed. Pressures between 1100 and 1900 bar and temperatures of 180 and 230°C were used. The average residence time was 40 seconds. Tertiary butyl perpivalate and tertiary butyl perethyl hexanoate in concentrations of 50 to 180 mol‐ppm in the ethylene feed were used as initiators. The characteristic properties of the polymers obtained were assessed by determining their composition, density, crystallinity, melting point, glass transition temperature, melt index, the average molecular weight, tensile strength and elongation at break.

Studies on new non‐shrinking, thermally stable araldite‐type photopolymers with pendent aryl acryloyl‐groups. II. Photoreaction of some arylacrylic‐acid methyl esters in the liquid state

AbstractLiquid aryl acrylic acid methyl esters, e.g. furan acrylic acid methyl ester and thienyl acrylic acid methyl ester, were UV‐irradiated (λ ≥ 280 nm) at a temperature of 2°C above their melting points. IR‐methods were used in order to monitor the photoreactions which are of a second order kinetics. The application of GC‐MS indicated that dimers, trimers and tetramers, but no polymers were formed under the chosen conditions.

Cyclopentadienyl-, Indenyl- und Trifluormethylcyclopentadienyl-Cobalt-Komplexe mit Akzeptor-substituierten Olefinen als Liganden / Cyclopentadienyl, Indenyl and Trifluoromethylcyclopentadienyl Cobalt Complexes with Acceptor-Substituted Olefins as Ligands

The complexes C5H5Co(PMe3)2 (1), C9H7Co(PMe3)2 (2) and (C5H4CF3)Co(PMe3)2 (3) react with mono- and disubstituted ethenes such as styrene, acrylic acid methylester, methylvinylketone, acroleine, acrylic acid amide, acrylonitrile, maleic anhydride, maleic and fumaric acid dimethylester, and fumaric dinitrile to give the olefin(phosphane)cobalt compounds (ring)Co(PMe3)(olefin) (4-32) in good to excellent yields. With acrylonitrile, two different rotamers are obtained which indicates that there is a considerable energy barrier for rotation around the metal-olefin bond. The reactions of 1 and 3 with maleic acid dimethylester (MDE) lead not only to the formation of the expected products (ring)Co(PMe3)(MDE) (22, 23) but also to the thermodynamically favored isomers (ring)Co(PMe3)(FDE) (24, 26) containing fumaric acid dimethylester (FDE) as ligand. A similar isomerization has been observed upon treatment of 2 and 3 with fumaric dinitrile (FDN) which gives besides the complexes (ring)Co(PMe3)(FDN) (29, 31) also the maleic dinitrile (MDN) derivatives (ring)Co(PMe3)(MDN) (30, 32). The olefin(trimethylphosphane)cobalt compounds are surprisingly inert and neither on photolysis nor on heating give the isomeric hydrido(vinyl)metal complexes.

1(3),2-Diacylglyceryl-3(1)- O-2′-(hydroxymethyl)( N, N, N,-trimethyl)-β-alanine (DGTA): A novel betaine lipid from Ochoromonas danica (Chrysophyceae)

The structure of lipid B, another betaine lipid from Ochromonas danica (Crysophyceae) has been elucidated by NMR, MS and IR data from the intact lipid and from derivatives obtained by chemical degradation. The structure of 1(3),2-diacylglyceryl-3(1)- O-2′- (hydroxymethyl)( N, N, N-trimethyl)-β-alanine (DGTA) has been assigned to the intact lipid which is a structural isomer of the already known homoserine lipid or 1(3),2-diacylglyceryl-3(1)- O-4′-( N, N, N-trimethyl)-homoserine (DGTS). 1(3),2- Diacylglyceryl-3(1)- O-2′-(hydroxymethyl)-propenoic acid was obtained from DGTA by deamination in chloroform with traces of formic acid. 1(3),2-diacylglycerol-3(1)- O-2′-(hydroxymethyl)-propanoic acid methyl ester was formed by treatment of DGTA with diazomethane in the presence of formic acid and by subsequent hydrogenation. From this compound, the corresponding diacetyl derivative was obtained by trans-esterification and acetylation. The diacetate was identical with synthetic 1(3),2-diacetylglyceryl-3(1)- O- 2′-(hydroxymethyl)-propanoic acid methyl ester, the preparation of which, starting from isopropylideneglycerol and 2-(bromomethyl)-acrylic acid methyl ester, is described. DGTA accounts for approximately 5% of the total lipids of O. danica. The major fatty acids of DGTA are 22:5 (42%), 18:0 (15%), 20:4 (13%); 20:2 (6%), 18:1 (5%), 20:3 (4%) 18:2 (4%), 22:4 (3%) and 16:0 (2%). From DGTA, trimethylamine is produced by a spontaneous deamination.

Tmeda-Nickel-Komplexe: IV. Synthese und Struktur von (tmeda)Ni(H 2CCHCOOCH 3) 2

Ni(C 2H 4) 3, Ni(cdt), or Ni(cod) 2 react with tmeda and acrylic acid methyl ester, methyl vinyl ether, and acrylonitrile in ether to afford (tmeda)Ni(H 2CCHCOOCH 3) 2 ( 3, orange-red crystals), (tmeda)Ni(H 2CCHCOCH 3) 2 ( 4, red crystals), and (tmeda)Ni(H 2CCHCN) 2 ( 5, yellow precipitate) in up to 90% yield. These complexes are also formed by interaction of the homoleptic bis(alkene) nickel(0) complexes Ni(H 2CCHCOOCH 3 2, Ni(H 2CCHCOCH 3 2, and Ni(H 2CCHCN) 2 with tmeda, and by the reaction of (tmeda)Ni(CH 3) 2 with the alkenes in ether at −30°C or above, under reductive elimination of ethane. Solid 3 is stable to about 110°C, whereas 4 decomposes slowly at 20°C; decomposition of 5 occurs at 136°C. The IR, 1H and 13C NMR spectra are reported. In addition, 3 has been characterized by an X-ray diffraction study.

Simple synthesis of α-methylene esters and amides from methacrylic derivatives via tosylated intermediates

Abstract ∝-(Tosylmethyl)acrylic acid methyl ester or N -isopropylamide (obtained by a tandem iodosulfonylation-dehydroiodination of methyl methacrylate or N -isopropylacrylamide) react with Grignard reagents or sodium diethyl malonate to give the corresponding ∝-methylene esters or amides in a regioselective manner.

Tmeda-Nickel-Komplexe: III. ( N,N,N′, N′-Tetramethylethylendiamin)-(dimethyl)nickel(II)

(tmeda)Ni(acac) 2 reacts with the main group metal compounds (tmeda)Mg-(CH 3) 2, (tmeda)&[;Al(CH 3) 3&]; 2, and (C 2H 5O)Al(CH 3) 2 at 0°C to give (tmeda)Ni-(CH 3) 2 ( 1), which can be isolated as fine yellow crystals in 50–80% yield. Complex 1, which is the simplest dialkyl nickel(II) compound with a “hard” donor ligand, is surprisingly stable and decomposes only at 79°C. 1 is converted by bipy to (bipy)Ni(CH 3) 2 and by Me 2PC 2H 4PMe 2 to (Me 2PC 2H 4PMe 2)Ni(CH 3) 2. Upon reaction of 1 with strong π-acceptor molecules (acrylic acid methylester, methyl vinyl ketone, acrylonitrile, tetracyanoethene, tetrafluoroethene, maleic anhydride) reductive elimination of the methyl groups takes place to give the complexes (tmeda)Ni(π-ligand) n ( n = 1, 2) and ethane.

Sulfur derivatives of 1‐methylpyrrole

AbstractMetalation of 1‐methylpyrrole using n‐butyllithium and tetramethylethylenediamine (TMEDA) in ether furnished 1‐methyl‐2‐pyrrolyllithium, which in turn was converted to 1‐methyl‐2‐methylthiopyrrole upon treatment with dimethyldisulfide. Further formylation with dimethylformamide, phosphorus oxychloride in dichloroethane led to the corresponding pyrrole‐2‐carboxaldehyde, which was then condensed with malononitrile and methylcyanoacetate under Knoevenagel reaction conditions to give 2‐cyano‐3‐(1‐methyl‐5‐methylthio‐2‐pyrrolyl)acrylonitrile and 2‐cyano‐3‐(1‐methyl‐5‐methylthio‐2‐pyrrolyl)acrylic acid methyl ester, respectively. Their oxidation by hydrogen peroxide furnished the corresponding sulfones. Analogously, 5‐phenylthio derivatives were prepared.

Synthesis of carrier ampholyte mixtures suitable for isoelectric fractionation analysis

A new procedure for the preparation of carrier ampholyte mixtures for isoelectric focusing is described. The procedure is based on the reaction of an α-, β-unsaturated carboxylic acid ester and a polyethylene polyamine followed by subsequent hydrolysis of the reaction products. The synthesis procedure is deseribed in detail using acrylic acid methyl ester and pentaethylenehexamine. Due to the high reaction velocity by which acrylic acid methyl ester adds to the amine moiety, it was possible to perform the synthesis in a controlled manner such that the obtained carrier ampholyte mixture exhibits a completely linear pH profile as well as uniform conductivity and buffering capacity without any additional manipulations. Furthermore, the procedure may also be applicable for the direct synthesis of carrier ampholytes covering restricted pH ranges. The high resolution capacity of the synthesized carrier ampholyte preparation is demonstrated by the fractionation of several test proteins.

ChemInform Abstract: CIDNP INVESTIGATION OF PHOTOINDUCED POLYMERIZATION

AbstractDie Photochemie und die charakteristischen Eigenschaften der Polymerisationsinitiatoren wp‐Dimethoxy‐wphenyl‐acetophenon, cop‐Diethoxy‐ und o:,eo‐Diisopropoxy‐acetophenon wurden mit Hilfe 1H‐ und "C‐chemisch induzierter Kempolarisation untersucht.

CIDNP.‐Investigation of Photoinduced Polymerization

AbstractThe photochemistry and some initiator characteristics of the polymerization initiators ω,ω‐dimethoxy‐ω‐phenyl‐acetophenone (A), ω,ω‐diethoxy‐acetophenone (B) and ω,ω‐diisopropoxy‐acetophenone (C) have been studied by 1H‐ and 13C‐chemically‐induced nuclear polarization (CIDNP.) experiments. The primary reaction of initiator A is a Norrish‐type I cleavage, while for B and C Norrish‐type I and Norrish‐type II cleavages are of comparable importance. Three different recombination products could be detected for initiator A which correspond to the three canonical resonance forms of the substituted benzyl radical.In a number of polymerization experiments the competition between reactions among initiator radicals and reactions of initiator radicals with the monomer acrylic acid methyl ester was studied at low concentrations of the monomer. These experiments give insight into the first steps of the polymerization process.The positive sign of the α‐hydrogen hyperfine couplings of the dimethoxy‐methyl‐ and the diisoproproxymethyl‐radicals could be established, in agreement with the deviation of these radicals from planarity.A slow square‐wave light‐modulation technique has been employed in 13C‐FT.‐experiments to measure absolute CIDNP.‐intensities.

Synthesen von Heterocyclen, CCIV1 Reaktionen mit cyclischen Oxalylverbindungen, XIX2 Eine einfache Synthese von 5-Benzoyl-6-phenyl-1.3-dioxin-4-onen / Syntheses of Heterocycles, CCIV1 Reactions of Cyclic Oxalyl Compounds, XIX 2 A Simple Synthesis of 5 Benzoyl-6-phenyl-1,3-dioxin-4-ones

4-Benzoyl-5-phenyl-2,3-dihydrofuran-2,3-dione (1) reacts with aldehydes or ketones via the acylketene-intermediate (2) yielding the 1,3-dioxin-4-ones (3). The aldehyde derivatives (3 a-e) can be converted into the anilino-chalcone (5) or the anilino acrylic acid (6) by treating with aniline at 20 °C. 6 and diazomethane combine to the acrylic acid methyl ester (7), which by heating (200 °C) is cyclisized to the quinolin-4-ole (8). On the other hand, the keto derivatives 3f-h and aniline give the dibenzoyl acetic acid anilide (9).