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Diffusion of perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) through 0.1 mm and 0.75 mm LLDPE and 0.1 mm and 0.75 mm LLDPE coextruded with ethyl vinyl alcohol (denoted as CoEx) at room temperature (23 °C), 35 °C, and 50 °C is examined. These tests had negligible source depletion throughout the monitoring period, indicating limited contaminant partitioning and diffusion through the LLDPE. At 483 days, 23 °C receptor PFOA and PFOS concentrations, cr, were

An efficient olefination protocol for the oxidative dehydrogenation of phenols and acrylates has been achieved using a palladium catalyst and O2 as the sole oxidant. This reaction exhibits high regio- and stereo-selectivity (E-isomers) with moderate to excellent isolated yields and a wide substrate scope (32 examples) including ethyl vinyl ketone and endofolliculina.

Pd-catalyzed decarboxylative allylic coupling of acetates of Baylis–Hillman alcohols with alkynyl carboxylic acids leading to the formation of an important class of 1,5-diarylpent-1-en-4-ynes in a highly regio- and stereoselective manner has been developed. Decarboxylative coupling happened via an exclusively SN2′ pathway. Acetates of the Baylis–Hillman alcohols derived from alkyl acrylates, ethyl vinyl ketone and phenyl vinyl sulfone provided exclusively (E)-1,5-diarylpent-1-en-4-ynes while the acetates of the Baylis–Hillman alcohols derived from acrylonitrile provided exclusively (Z)-1,5-diarylpent-1-en-4-ynes.

Photo responsive polyethyl vinyl ketone (PEVK) and various block copolymers were prepared through the visible light induced cobalt mediated radical polymerization (CMRP) process. The first order kinetics and linear increase in molecular weight with conversion demonstrated a well-behaved system. Chain extension experiments showed the retention of the living end of PEVK.

Glycerol was used as a reaction medium as well as promoter for aza-Michael addition of aromatic amines to electronic deficient α,β-unsaturated ketones. Various aromatic amines can react smoothly with chalcone, 2-cyclohexen-1-one, 2-cyclopenten-1-one, and ethyl vinyl ketone to achieve good to excellent yields in the absence of any catalyst.

Various N-tosyl arylimines reacted with methyl vinyl ketone and ethyl vinyl ketone in the presence of ion-supported Ph3P A and B to give adducts, N-(2′-methylene-3′-oxo-1′-arylbutyl)-4-methylbenzenesulfonamides and N-(2′-methylene-3′-oxo-1′-arylpentyl)-4-methylbenzenesulfonamides, respectively, in good yields with high purity by simple diethyl ether extraction of the reaction mixture. Moreover, ion-supported Ph3P A and B could be repeatedly used for the same reaction to provide the corresponding adducts while maintaining good yields with high purity.

A simple and efficient one-pot synthesis of polyfunctionalized benzenes has been developed via cyclocondensation of activated α-methylene alkenes such as vinyl malononitriles and ethyl vinyl cyanoacetates with nitroolefins using Cu(OTf) 2 /Et 3 N as a novel catalytic system.

A series of chiral sterically congested phosphane-amide bifunctional Lewis bases L1-L3 have been successfully synthesized and their application in asymmetric aza-Morita-Baylis-Hillman (aza-MBH) reactions of N-sulfonated imines with activated olefins such as methyl and ethyl vinyl ketone has been investigated under mild conditions. The corresponding aza-MBH adducts can be obtained in good-to-excellent yields (up to 98%) and moderate-to-good enantioselectivities (up to 91 or 93 % ee) in dichloromethane at room temperature (20 degrees C) with these novel chiral bifunctional phosphane Lewis bases. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008).

Reactions of salicyl N-tosylimines with methyl vinyl ketone, ethyl vinyl ketone or phenyl vinyl ketone proceeded smoothly under mild conditions to give the corresponding chromanes or aza-Baylis–Hillman adducts in moderate to excellent yields in the presence of phosphine or nitrogen Lewis base.

The purpose of the study was to determine the effect of ethyl vinyl chloride vapocoolant spray on pain reported by children undergoing intravenous cannulation. A randomized, double-blinded, placebo-controlled trial was conducted on eligible children between the ages of 9 and 18 years seen in a pediatric emergency department and requiring intravenous cannulation. Informed consent was obtained, and children were randomized to receive ethyl vinyl chloride spray, isopropyl alcohol spray, or no spray (control group). Patient demographics and information pertaining to each intravenous cannulation were recorded. Children indicated the degree of pain associated with intravenous cannulation on a 100-mm visual analog scale (VAS) compared to a baseline pain score of “zero.” Statistical analysis was performed by using Stata version 7. One hundred twenty-seven subjects were enrolled: 37 received ethyl vinyl chloride vapocoolant spray, 48 received isopropyl alcohol spray (placebo), and 42 received no pretreatment. Mean VAS scores for pain experienced during cannulation were 34, 33, and 31 mL for each group, respectively. Ethyl vinyl chloride vapocoolant spray failed to measurably reduce pain associated with intravenous cannulation when compared to those pretreated with isopropyl alcohol spray or receiving no intervention.

Cyclic s-cyano ketones like cyanocarvone and 3-cyano-2-methylcyclopentanone can be annelated in high yields with methyl vinyl ketone, ethyl vinyl ketone and 6(3- methoxyphenyl)hex-1-en-3-one to cyano-substituted decalones and indanones. Computational studies at the B3LYP/6-31+G(d,p)//B3LYP/6-31G(d,p) level of theory show that thermodynamic rather than kinetic factors can explain the high yields. The annelated products are suitable intermediates for the synthesis of isoprenoid, steroid and homo steroid skeletons

Substituted N-[2-(vinyloxy)ethyl]pyrroles, prepared in good yield through an allenic or acetylenic carbanion/isothiocyanate one-pot methodology from 2-(vinyloxy)ethyl isothiocyanate and allyloxyallene, methoxyallene, N,N-dimethyl-2-propyn-1-amine, and 3-methoxy-1-(methylsulfanyl)-1-propyne, are smoothly converted into the corresponding N-vinylpyrroles using t-BuOK/DMSO (room temperature). The reaction proceeds via elimination of vinyl alcohol from the N-[2-(vinyloxy)ethyl] substituent and represents a novel approach to N-vinylpyrroles.

The catalytic hydrogenation of saturated and unsaturated ketones and aldehydes in the presence of [Ir(CO)(PPh 3 )(2-Ph 2 PC 6 H 4 NR-κ N ,κ P )] (R=H: 1 ; R=Me: 2 ), [Rh(CO)(PPh 3 )(2-Ph 2 PC 6 H 4 NR-κ N ,κ P )] (R=H: 3 ; R=Me: 4 ), [Rh(PPh 3 ) 2 (2-Ph 2 PC 6 H 4 NH-κ N ,κ P )] ( 5 ), and [Ir(CO)(PPh 3 )(2-Ph 2 PC 6 H 4 N{C(O)camph-(1 S )}-κ N ,κ P )] ( 6 , C(O)camph-(1 S )=(1 S )-camphanoyl) has been investigated. Out of the complexes tried, only 1 showed significant activity for the reduction of the carbonyl group. Evidence is presented that the catalytic cycle is entered by the formation of the cis- ( H , H ) -cis- ( P , P )-dihydride [IrH 2 (CO)(PPh 3 )(2-Ph 2 PC 6 H 4 NH-κ N ,κ P )] ( 9a ) which can be observed by 1 H NMR under 45 bar H 2 . The homogeneous hydrogenation of five α,β-unsaturated carbonyl compounds (crotonaldehyde, ethyl vinyl ketone, 2-cyclohexen-1-one, benzylideneacetone, and benzylideneacetophenone), in the presence of 1 , proceeded with chemoselectivities for the corresponding allylic alcohols varying between zero for EtC(O)CHCH 2 and 77–78% for PhCHCHC(O)Me and MeCHCHCHO, respectively. Complexes 1 and 5 were fully characterized by X-ray structure analysis.

Novel pincer palladium complexes having chiral hexahydro-1H-pyrrolo[1,2-c]imidazolone groups were designed and prepared. Catalytic asymmetric Michael addition of isopropyl 2-cyanopropionate to ethyl vinyl ketone was catalyzed by the chiral pincer palladium complex to give isopropyl 2-cyano-2-methyl-5-oxoheptanoate with high enantioselectivity (up to 83% ee). [structure: see text]

Two effective synthetic approaches to (±)-euryfuran 1 are described. One synthetic route makes use of sequential furan ring transfer reaction type I and type III as key steps followed by Eschenmoser-type [3,3]sigmatropic rearrangement, and another route proceeded through furan ring transfer reaction type I and annulation with ethyl vinyl ketone subsequently.

Substituted N-[2-(vinyloxy)ethyl]pyrroles, prepared in good yield through an allenic or acetylenic carbanion/isothiocyanate one-pot methodology from 2-(vinyloxy)ethyl isothiocyanate and allyloxyallene, methoxyallene, N,N-dimethyl-2-propyn-1-amine, and 3-methoxy-1-(methylsulfanyl)-1-propyne, are smoothly converted into the corresponding N-vinylpyrroles using t-BuOK/DMSO (room temperature). The reaction proceeds via elimination of vinyl alcohol from the N-[2-(vinyloxy)ethyl] substituent and represents a novel approach to N-vinylpyrroles.

Pressures of as little as 500 bar have been shown to exert a substantial effect upon rates and product ratios of ortho and meta photocycloadditions of ethenes to the benzene ring. In all cases, rates are enhanced by pressure and calculated ‘pseudo-activation volumes’ for both modes of addition appear to be of similar magnitude to those of thermal cycloaddition processes. The pressure-induced discrimination between isomeric meta cycloadducts from the ethyl vinyl ether–benzene system is rationalised in terms of the mechanism involving partial charge separation in the S1 arene and is backed up by calculated molar volumes of the adducts. Similar results are observed for the intramolecular photocycloaddition reactions of arene–ethene non-conjugated bichromophores.

An asymmetric Diels–Alder reaction between 1-phenyl-3,4-dimethylphosphole and ethyl vinyl ketone promoted by a chiral organopalladium complex gives the corresponding keto-substituted phosphine ligands in which the keto group can be stereospecifically located in the endo- or exo-positions of the phosphanorbornene skeleton.

(5R)-3-Methyl-5-phenyl-5H,7H-thiazolo[3,4-c]oxazol-4-ium-1-olate was generated in the presence of a range of dipolarophiles. The intermolecular 1,3-dipolar cycloaddition of this mesoionic species led to the synthesis of chiral 1H-pyrrolo[1,2-c]thiazole derivatives 7a, 7b, 8, 14, 18, 19 and 20. In the reaction with methyl and ethyl vinyl ketone, spiro compounds 9 and 15 were also obtained. The structure of compound 15 was determined by X-ray crystallography.

The structures and energies of a series of ethyl, vinyl, isopropyl, and cyclopropyl derivatives were calculated via ab initio MO theory using the 6-31G * basis set. The substituents were H, Li, BeH, BH 2 , CH 3 , NH 2 , OH, F, SiH 3 , PH 2 , and Cl. The energies of isodesmic reactions were calculated, and in the exchange of H and X between isopropyl and cyclopropyl the electronegative groups were found to prefer the isopropyl group whereas the electropositive groups preferred the cyclopropyl group

[figure: see text] The total synthesis of racemic eremopetasidione, a norsesquiterpenoid, has been achieved in nine steps and 30% overall yield starting from creosol (5). Diels-Alder reaction of masked o-benzoquinone 6 and ethyl vinyl ketone and Cope rearrangement of 2-silyloxy-1,5-dienone 3 are the key steps.

The Michael reaction of (+)-2-caranone (1) with methyl vinyl ketone, ethyl vinyl ketone or methyl acrylate was utilized for synthesis of corresponding diketones4 and5 and keto ester8. These compounds were subjected to cyclization to obtain the sesquiterpenoid systems.

Reactions of salicyl N-tosylimines with methyl vinyl ketone, ethyl vinyl ketone or phenyl vinyl ketone proceeded smoothly under mild conditions to give the corresponding chromanes or aza-Baylis–Hillman adducts in moderate to excellent yields in the presence of phosphine or nitrogen Lewis base.

主鎖にβ-ラクトン単位を含むポリマ-を合成する研究の一環として, シトラコン酸エチルビニル (EVC) のラジカル環化重合をベンゼン中, 70℃で行った. EVCモノマーの合成において, エステル基の位置が異なる二つの異性体, CH2=CHOCOC (CH3) =CHCOOC2H5, CH2=CHOCOCH=C (CH3) COOC2H5が1.15: 1の比率で伴われたが, 両者の分離は成功しなかった. この両異性体混合物の環化重合において, マレイン酸エチルビニルの場合と同様に低モノマー濃度における重合で, 主鎖にβ-ラクトン単位のみを含むポリマーを与えたが, 異なるモノマー構造に由来すると考えられるα-メチル, β-プロピオラクトンとβプロビオラクトンの二種のラクトン単位を0.4: 0.6の比率で含むことを認めた. ポリマーに残存する不飽和基はビニル基に比べシトラコン酸二重結合を2.7～3倍多く含むが, これは重合におけるシトラコン酸二重結合上のメチル基への退化的連鎖移動によると推論された.

Aza-Morita–Baylis–Hillman (aza-MBH) reaction of ethyl (arylimino)acetate with methyl vinyl ketone and ethyl vinyl ketone has been investigated. We found that aza-MBH adducts 1 could be formed in the presence of DABCO (30 mol %) and the corresponding adducts 2 could be obtained in the presence of PPh 3 (30 mol %) in moderate to good yields in acetonitrile under mild conditions, respectively.

The reaction between N-acyl-6-amino-3-(methylthio)-1,2,4,5-tetranizes 1 with electron-rich dienophiles 2 gives the corresponding 1,2-diazines 3 in excellent yields and with high regioselectivity (Scheme 30.1).

The endovascular treatment of intracranial aneurysms has evolved over the last decade from a timid alternative to surgical clipping to a very well accepted universally expanding form of therapy. Recent randomized clinical trials (ISAT) have legitimized the advantages of the endovascular treatment over surgery. The mainstay of the endovascular treatment is the electrically detached platinum coil introduced in the early nineties by Guido Guglielmi (GDC). The GDC influenced favorably the acceptance of endovascular treatment of aneurysms due primarily to its efficacy, ease of use and reliability. More and more physicians from different disciplines have learned the basic techniques of endovascular treatment and are now practicing them. The associated mortality and morbidity continue to improve steadily. Several improvements have been made to the GDC which have resulted in a better safety record and better long term anatomical results. These improvements include: a smaller gauge primary wire, a “soft” and “ultrasoft” version, a faster and more reliable detachment mechanism, a stretch-resistant coil, etc. However, and despite these improvements, there remains a major drawback to the use of GDC which is the poor long term anatomical results, i.e. high recanalization rate, in large and giant aneurysms and in aneurysms with a wide neck. Whereas the long term anatomical results are good in small aneurysms with small neck, large aneurysms with wide neck have an unacceptably high rate of recanalization of at least 20 to 30%. Several new technologies have emerged for the purpose of improving the efficacy of bare platinum coils. These include: 1 - New complex-shaped coils that conform better to complex-shaped or large aneurysms and therefore produce a better obliteration rate, particularly in the long term. 2 - Faster detachment mechanism which is more reliable than the original electrolytic detachment. 3 - Adding an expansile material to the platinum coil such as hydrogel to improve the fill-factor of the aneurysm and therefore the long term obliteration rate. 4 - Modifying the surface of the platinum coils to induce more fibrous tissue within the aneurysm and therefore accelerate the healing process. The surface modifiers that have been used so far include a polyglycolic acid (PGLA) polymer and a radioactive isotope (P32). In addition to modifying platinum coils, other devices have been introduced as adjuncts to coiling. These include: 1 - The Trispan® neck bridge device designed primarily to aid in the packing of terminal and bifurcation wide-neck aneurysms with platinum coils. 2 - Low-profile balloon-expandable metallic stents designed primarily for the reconstruction of the parent artery in large and wide-neck aneurysms. 3 - Flexible and low-profile self expanding stents made of Nintinol and designed for the reconstruction of the parent artery. 4 - Flexible covered stents designed to exclude large and giant aneurysms from the Parent Circulation. Other embolic agents have also been developed either as replacement or adjunct to platinum coils in the endovascular treatment of aneurysms. These include: 1 - Ethyl Vinyl Alcohol (EVOH) polymer dissolved in Dimethyl Sulfoxide (DMSO) commercialized under the trade name of Onyx®. 2 - Derivatives of Cyanoacrylate such as Neuracryl®.

A complex case of carotid-cavernous fistula was treated transvenously by injection of ethyl vinyl alcohol co-polymer into the cavernous sinus after an unsuccessful embolization attempt with detachable coils and liquid adhesive agents. There were no complications. At 3 months the patient's symptoms had resolved completely, and a control angiogram revealed persistent occlusion. The physical properties of ethyl vinyl alcohol polymer justify further investigation of this agent for the treatment of carotid-cavernous fistula.

Over the past decade, olefin metathesis has emerged as a powerful method for the formation of carbon-carbon double bonds [1]. In particular, two ruthenium-based catalysts- (PCy3)2(Cl)2Ru=CHPh (1)

(5R)-3-Methyl-5-phenyl-5H,7H-thiazolo[3,4-c]oxazol-4-ium-1-olate was generated in the presence of a range of dipolarophiles. The intermolecular 1,3-dipolar cycloaddition of this mesoionic species led to the synthesis of chiral 1H-pyrrolo[1,2-c]thiazole derivatives 7a, 7b, 8, 14, 18, 19 and 20. In the reaction with methyl and ethyl vinyl ketone, spiro compounds 9 and 15 were also obtained. The structure of compound 15 was determined by X-ray crystallography. http://www.sciencedirect.com/science/article/B6THR-407GGNF-K/1/23c3db756f6ed9f6caefffc1d46ba51a

The hetero-Diels-Alder reaction of carbonyl compounds with conjugated dienes [eq (1)] constitutes one of the cornerstone reactions in organic chemistry.1 The products formed in this reaction are of fundamental importance in chemistry, and numerous examples of the use of these compounds in academia and industry have appeared.