Methyl vinyl ketone

About: Methyl vinyl ketone is a research topic. Over the lifetime, 1510 publications have been published within this topic receiving 26839 citations. The topic is also known as: 3-buten-2-one & gamma-oxo-alpha-butylene.

Heterogeneous reactions of methacrolein and methyl vinyl ketone on α-Al2O3 particles

Abstract: The heterogeneous reactions of methacrolein (MAC) and methyl vinyl ketone (MVK) on α-Al(2)O(3) surfaces have been studied in a flow reactor using transmission-Fourier Transform Infrared (T-FTIR) spectroscopy to monitor the reaction progress. Unlike SiO(2) particles where MAC and MVK are weakly physisorbed, the results in this work demonstrate that on c-AlO3 particles MAC and MVK are irreversibly adsorbed and can rapidly react on the surface to form various products such as aldehydes, organic acids, hydrogen peroxide, and even higher molecular weight compounds. The initial uptake rates and initial uptake coefficients for MAC and MVK on α-Al(2)O(3) under dry conditions were determined to explore the reactivity of the particles. Furthermore, the effect of water vapor on the heterogeneous reactions was also investigated as a function of relative humidity. Both the heterogeneous uptake and transformation of MAC and MVK on α-Al(2)O(3) were largely suppressed under humid conditions due to the depletion of surface active sites by water molecules. On the basis of experimental results, atmospheric implications of heterogeneous reactions of MAC and MVK were discussed. Our work suggests that heterogeneous reactions on α-Al(2)O(3) can be important sinks for MAC and MVK as well as possible contributors to atmospheric organic aerosol.

The Mechanism of Vinyl Polymerization by Dialkylbis(dipyridyl)iron(II)

Abstract: Kinetics of polymerization of vinyl compounds (acrylonitrile, methacrylonitrile, acrolein, methyl vinyl ketone, methyl acrylate, alkyl methacrylates, and 2-vinylpyridine) with dialkylbis(dipyridyl)iron(II), FeR2(dipy)2 1 (R=CH3, C2H5, n-C3H7), was studied. By comparison with previous kinetic results in which the decomposition of 1 was followed spectroscopically, a polymerization mechanism including a slow initiation process followed by rapid propagation and unimolecular termination processes was proposed. The effects of the concentration of monomer, the addition of dipyridyl and the coordinating ability of solvent on the molecular weight of the polymer were explained by competitive coordination to the iron complex having a growing polymer chain. Results of copoly-merization experiments were explained in terms of competitive coordination and insertion reactions between the monomers involved. A linear relationship was found between log(1⁄r1) values and the logarithms of stability constants of nickel-olefin ...

Umpolung Reactions of α-Imino Esters: Useful Methods for the Preparation of α-Amino Acid Frameworks.

Abstract: This paper summarizes our recent efforts toward the development of tandem reactions utilizing umpolung reactions of α-imino esters. A highly diastereoselective tandem N-alkylation-Mannich reaction of α-imino esters was developed. A tandem N-alkylation-addition reaction of α-imino esters derived from ethyl glyoxylate with various aldehydes proceeded to give 1,2-amino alcohols. The same reaction also proceeded efficiently using a novel flow system comprising two connected microreactors. Novel syntheses of α-quaternary alkynyl amino esters and allenoates were developed through the use of umpolung N-addition to β,γ-alkynyl α-imino esters, followed by regioselective acylation. In addition, a highly regioselective tandem N-alkylation-vinylogous aldol reaction of β,γ-alkenyl α-imino esters was discovered. N-Alkylation of α-iminophosphonates followed by a Horner-Wadsworth-Emmons reaction with aldehydes occurred to afford enamines, which can be used in a four-component coupling reaction with methyl vinyl ketone. α-N-Acyloxyimino esters served as highly efficient substrates for the N,N,C-trialkylation reaction to introduce various nucleophiles at the imino nitrogen and carbon atoms.