6295-06-3Relevant articles and documents
Photodegradation of butyl acrylate in the troposphere by OH radicals: Kinetics and fate of 1,2-hydroxyalcoxy radicals
Blanco, Maria B.,Teruel, Mariano A.
, p. 397 - 401 (2008)
The rate constant of the reaction of OH radicals with butyl acrylate was studied for the first time using an atmospheric simulation chamber at 298 K and ～750 Torr of air or nitrogen. The decay of the organics was followed using a gas Chromatograph with a flame ionization detector (GC-FID), and the rate constant was determined using a relative rate method with different references. The obtained average value of (1.80 ± 0.26) × 10-11 cm3 molecule-1 s-1 is in agreement with previous determinations of the rate constants of OH radicals with acrylates and methacrylates in the literature. Additionally, product identification under atmospheric conditions was performed for the first time by the GC-MS technique. Butyl glyoxalate was observed as the degradation product in accordance with the addition of OH to the less substituted carbon atom of the double bond, followed by decomposition of the 1,2-hydroxyalkoxy radicals formed. Room temperature rate coefficient was used to estimate the atmospheric lifetime of the ester studied. Reactivity trends are discussed in terms of the substituent effects and the length of the hydrogenated chain of the ester. The atmospheric persistence of BUAC was calculated taking into account the experimental rate constant obtained. Copyright
One-pot multicomponent synthesis of novel 2-(piperazin-1-yl) quinoxaline and benzimidazole derivatives, using a novel sulfamic acid functionalized Fe3O4 MNPs as highly effective nanocatalyst
Esam, Zohreh,Akhavan, Malihe,Bekhradnia, Ahmadreza
, (2020/10/27)
The immobilization of sulfonic acid on the surface of Fe3O4 magnetic nanoparticles (MNPs) as a novel acid nanocatalyst has been successfully reported. The morphological features, thermal stability, magnetic properties, and other physicochemical properties of the prepared superparamagnetic core–shell (Fe3O4@PFBA–Metformin@SO3H) were thoroughly characterized using Fourier transform infrared (FTIR), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), thermogravimetric analysis–differential thermal analysis (TGA-DTA), atomic force microscopy (AFM), dynamic light scattering (DLS), Brunauer–Emmett–Teller (BET), and vibrating sample magnetometer (VSM) techniques. It was applied as an efficient and reusable catalyst for the synthesis of 2-(piperazin-1-yl) quinoxaline and benzimidazole derivatives via a one-pot multiple-component cascade reaction under green conditions. The results displayed the excellent catalytic activity of Fe3O4@PFBA–metformin@SO3H as an organic–inorganic hybrid nanocatalyst in condensation and multicomponent Mannich-type reactions. The easy separation, simple workup, excellent stability, and reusability of the nanocatalyst and quantitative yields of products and short reaction time are some outstanding advantages of this protocol.
PROCESS FOR PREPARATION OF ACITRETIN
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Page/Page column 9, (2016/04/20)
The present invention provides a process for preparation of {(2E,4E,6E,8E)-9-(4-methoxy-2,3,6- trimethyl)phenyl-3,7-dimethyl-nona-2,4,6,8}tetraenoate, an acitretin intermediate of formula (VI) with trans isomer ≥97%, comprising of reacting 3-formyl-crotonic acid butyl ester of formula (V), substantially free of impurities, with 5-(4-methoxy-2,3,6-trimethylphenyl)-3- methyl-penta-2,4-diene-l-triphenyl phosphonium bromide of formula (IV) and isolating resultant compound of formula (VI), treating the filtrate with iodine for isomerization of the undesired cis intermediate and finally obtaining acitretin (I), with desired trans isomer ≥97%.
Polyglyoxylates: A versatile class of triggerable self-immolative polymers from readily accessible monomers
Fan, Bo,Trant, John F.,Wong, Andrew D.,Gillies, Elizabeth R.
, p. 10116 - 10123 (2014/08/05)
Self-immolative polymers, which degrade by an end-to-end depolymerization mechanism in response to the cleavage of a stabilizing end-cap from the polymer terminus, are of increasing interest for a wide variety of applications ranging from sensors to controlled release. However, the preparation of these materials often requires expensive, multistep monomer syntheses, and the degradation products such as quinone methides or phthalaldehydes are potentially toxic to humans and the environment. We demonstrate here that polyglyxoylates can serve as a new and versatile class of self-immolative polymers. Polymerization of the commercially available monomer ethyl glyoxylate, followed by end-capping with a 6-nitroveratryl carbonate, provides a poly(ethyl glyoxylate) that depolymerizes selectively upon irradiation with UV light, ultimately generating ethanol and the metabolic intermediate glyoxylic acid hydrate. To access polyglyoxylates with different properties, the polymerization and end-capping approach can also be extended to other glyoxylate monomers including methyl glyoxylate, n-butyl glyoxylate, and benzyl glyoxylate, which can be easily prepared from their corresponding fumaric or maleic acid derivatives. Random copolymers of these monomers with ethyl glyoxylate can also be prepared. Furthermore, using a multifunctional end-cap that is UV-responsive and also enables the conjugation of another polymer block via an azide-alkyne "click" cycloaddition, amphiphilic self-immolative block copolymers are also prepared. These block copolymers self-assemble into micelles in aqueous solution, and their poly(ethyl glyoxylate) blocks rapidly depolymerize upon UV irradiation. Overall, these strategies are expected to greatly expand the utility of self-immolative polymers by providing access for the first time to self-immolative polymers with tunable properties that can be readily obtained from simple monomers and can be designed to depolymerize into nontoxic products.
