It's no Vinylic Lip, but the color payoff is best described as your-lips-but-better, with a naturally flushed, glazed finish.
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The new Playground line includes four products — Colorslide gel-pencil eyeliner, Niteshine highlighter, Glitter Gelée eyeshadow, and Vinylic Lip lacquer — all available in a rainbow of shades.
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Also launching: the $14 Glitter Gelée makeup topper, made to turn anything sparkly for a 12-hour run, and a $16 Vinylic Lip click pen, which aims to deliver high shine and deep color without staining or feathering.
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Vinylic selenides are organoselenium compounds that play a role in organic synthesis, especially in the development of convenient stereoselective routes to functionalized alkenes. Although various methods are mentioned for the preparation of vinylic selenides, a more useful procedure has centered on the nucleophilic or electrophilic organoselenium addition to terminal or internal alkynes. For example, the nucleophilic addition of selenophenol to alkynes affords, preferentially, the Z-vinylic selenides after longer reaction times at room temperature.The reaction is faster at a high temperature; however, the mixture of Z- and E-vinylic selenides was obtained in an almost 1:1 ratio.
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The vinyl cation is a carbocation with the positive charge on an alkene carbon. Its empirical formula is . More generally, a vinylic cation is any disubstituted, trivalent carbon, where the carbon bearing the positive charge is part of a double bond and is sp hybridized. In the chemical literature, substituted vinylic cations are often referred to as vinyl cations, and understood to refer to the broad class rather than the variant alone.
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On the other hand, the adducts depend on the nature of the substituents at the triple bond. Conversely, vinylic selenides can be prepared by palladium-catalyzed hydroselenation of alkynes to afford the Markovnikov adduct in good yields. There are some limitations associated with the methodologies to prepare vinylic selenides illustrated above; the procedures described employ diorganoyl diselenides or selenophenol as starting materials, which are volatile and unstable and have an unpleasant odor. Also, the preparation of these compounds is complex.
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In 1983, Cacchi and coworkers disclosed a reductive Heck arylation of enones and enals in the presence of a trialkylamine base, tetrabutylammonium halide, and formic acid additive. Under these conditions, the conjugate addition product is formed preferentially to the vinylic substitution (Mizoroki–Heck) product in high yield and selectivity. Notably, reductive Heck coupling on enones/enals features some mechanistically distinct aspects, as described in studies by Cacchi and later Minnaard. Both the conjugate addition and vinylic substitution mechanisms proceed through a common alkylpalladium(II) intermediate 34.
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Intersystem crossing and radical recombination results in equal quantities of semibullvalenes 3 and 4. The new proton distribution with allylic, vinylic and cyclopropanyl protons determined with proton NMR confirms this model. As noted, the conversion of barrelene to semibullvalene is a di-pi-methane rearrangement. Scheme 4.
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Tile alkyl group R should be primary or methyl, and preferably should be allylic or benzylic. Secondary halides react poorly, and tertiary halides don't react at all because a competing E2 elimination of HX occurs instead. Vinylic and aryl halides are also unreactive because backside approach is sterically prevented.
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The initial steps are straightforward. The phenyl sulfone anion (2) reacts with an aldehyde to form the alkoxide (3). The alkoxide is functionalized with R3-X to give the stable intermediate (4). The exact mechanism of the sodium amalgam reduction is unknown but has been shown to proceed through a vinylic radical species (5).
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Targeting and inhibiting 3C protease activity will hopefully reduce the infectivity of the host cell. For poliovirus, Bis-vinylic organotellurane targets 3C inhibition, which is used as antiviral therapy. Currently no anti-picornal drug targeting 3C protease is in the market yet, but inhibitors such as rupintrivir and pyrazoles show promising targeting in broad range of picornaviruses.
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Protonation of the vinylic radical gives the desired product (6). Julia olefination mechanism wiki The stereochemistry of the alkene (6) is independent of the stereochemistry of the sulfone intermediate 4. It is thought that the radical intermediates are able to equilibrate so that the more thermodynamically stable trans-olefin is produced most often. This transformation highly favors formation of the E-alkene.
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While steric effects are still important in determining the outcome of a Lewis acid catalyzed ene reaction, electronic effects are also significant, since in such a reaction, there will be a considerable positive charge developed at the central carbon of the ene. As a result, alkenes with at least one disubstituted vinylic carbon are much more reactive than mono or 1,2-disubstituted ones.
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Alkynes characteristically are capable of adding two equivalents of halogens and hydrogen halides. :RC≡CR′ + 2 Br2 → RCBr2CR′Br2 The addition of nonpolar E–H bonds across C≡C is general for silanes, boranes, and related hydrides. The hydroboration of alkynes gives vinylic boranes which oxidize to the corresponding aldehyde or ketone. In the thiol-yne reaction the substrate is a thiol.
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Despite his objections, Noi used her magic to heal Shin, costing her chance at becoming a devil as result, a choice she does not regret. Noi's mask is very detailed, dark blue and apparently vinylic. ; : :Fujita is a low-level who works for a company headed by En. :His partner is killed by Caiman. He is assigned to find the Sorcerer who transformed Caiman into a saurian.
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The name is also used for any compound containing that group, namely R−CH=CH2 where R is any other group of atoms. An industrially important example is vinyl chloride, precursor to PVC, a plastic commonly known as vinyl. Chessboard made from polyvinyl chloride Vinyl is one of the alkenyl functional groups. On a carbon skeleton, sp2-hybridized carbons or positions are often called vinylic.
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Derivatization of these PFCA rings via displacement of fluorine atoms with nucleophiles occurs through an addition-elimination reaction in the presence of a base. Attack of the nucleophile on the PFCA ring generates a carbanion which can eliminate a fluoride ion, resulting in vinyl substituted and allyl substituted products (Scheme 1). The ratio of vinylic to allylic products depends on the ring size, reaction conditions and nucleophile. Scheme 1.
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One insight into the reaction mechanism for this photoreaction is given by an isotope scrambling experiment. The 6 vinylic protons in barrelene 1 are more acidic than the two bridgehead protons and therefore they can be replaced by deuterium with N-deuteriocyclohexylamide. Photolysis of 2 results in the initial formation of a biradical intermediate with a cyclopropane ring formed. This product rearranges to a second intermediate with a more favorable allylic radical as two mesomers.
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The Wulff–Dötz reaction (also known as the Dötz reaction or the benzannulation reaction of the Fischer carbene complexes) is the chemical reaction of an aromatic or vinylic alkoxy pentacarbonyl chromium carbene complex with an alkyne and carbon monoxide to give a Cr(CO)3-coordinated substituted phenol. Several reviews have been published. It is named after the German chemist Karl Heinz Dötz (b. 1943) and the American chemist William D. Wulff (b.
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Gomes, J. A. N. F.; Mallion, R. B. Chem. Rev.; (Review); 2001; 101(5); 1349-1384. The effect helps distinguish these nuclear environments and is therefore of great use in molecular structure determination. In benzene, the ring protons experience deshielding because the induced magnetic field has the same direction outside the ring as the external field and their chemical shift is 7.3 ppm compared to 5.6 for the vinylic proton in cyclohexene.
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Generation of a vinyl cation reactive intermediate. Adapted from Vinyl cations have been observed as reactive intermediates during solvolysis reactions. Consistent with SN1 chemistry, these reactions follow first order kinetics. Generally, vinylic halides are unreactive in solution: silver nitrate does not precipitate silver halides in the presence of vinyl halides, and this fact was historically used to dispute the existence of the vinyl cation species. The introduction of “super” Leaving group in the 1970s first allowed for the generation of vinyl cation reactive intermediates with appreciable lifetimes.
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Whereas enols are neutral, enolate ions are negatively charged, making them much better nucleophiles. As a result, enolate ions are more common than enols in both laboratory and biological chemistry. Because they are resonance hybrids of two nonequivalent forms, enolate ions can be looked at either as vinylic alkoxides (C=C- O−) or as α-ketocarbanions (−C-C= O). Thus, enolate ions can react with electrophiles either on oxygen or on carbon. Reaction on oxygen yields an enol derivative, while reaction on carbon yields an α-substituted carbonyl compound.
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Due to the electron- withdrawing effect of the ring nitrogen atom, 2-vinylpyridine adds nucleophiles such as methoxide, cyanide, hydrogen sulfide at the vinylic site to give addition products. The addition product of methanol to 2-vinylpyridine, 2-(2-methoxyethyl)pyridine is a veterinary anthelmintic. Treating 2-vinylpyridine with 4-pyridinecarbonitrile and hydrogen chloride gives 1-[2-(2-pyridyl)ethyl]-4-cyanopyridinium chloride, which then can be used to prepare dimethylaminopyridine (DMAP), a widely used base catalyst. 2-Vinylpyridine is used in the production of Axitinib, a pharmaceutical.
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The intermolecular oxidations of olefins with alcohols as nucleophile typically generate ketals, where as the palladium-catalyzed oxidations of olefins with carboxylic acids as nucleophile genreats vinylic or allylic carboxylates. In case of diols, their reactions with alkenes typically generate ketals, whereas reactions of olefins bearing electron-withdrawing groups tend to form acetals. Palladium- catalyzed intermolecular oxidations of dienes with carboxylic acids and alcohols as donors give 1,4-addition products. In the case of cyclohexadiene (Figure 4, A), Backvall found that stereochemical outcome of product was found to depend on concentration of LiCl.
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MeAN can undergo electropolymerization, if it is submitted to electroreduction at metallic cathodes in an organic anhydrous medium, for example; acetonitrile. There are two types of polymers that can be obtained at the end of the synthesis; a physisorbed polymer and a grafted polymer. The mechanism accounting for the non-grafted polymer is pretty well understood: it proceeds via the formation of a radical anion (the product of reduction of the vinylic monomer), which dimerizes in solution because of a radical–radical coupling mechanism (RRC) to deliver a di-anion acting as the initiator of a polymerization reaction in solution.
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Allenes differ considerably from other alkenes in terms of their chemical properties. Compared to isolated and conjugated dienes, they are considerably less stable: comparing the isomeric pentadienes, the allenic 1,2-pentadiene has a heat of formation of 33.6 kcal/mol, compared to 18.1 kcal/mol for (E)-1,3-pentadiene and 25.4 kcal/mol for the isolated 1,4-pentadiene. The C–H bonds of allenes are considerably weaker and more acidic compared to typical vinylic C–H bonds: the bond dissociation energy is 87.7 kcal/mol (compared to 111 kcal/mol in ethylene), while the gas-phase acidity is 381 kcal/mol (compared to 409 kcal/mol for ethylene), making it slightly more acidic than the propargylic C–H bond of propyne (382 kcal/mol). The 13C NMR spectrum of allenes is characterized by the signal of the sp-hybridized carbon, resonating at a characteristic 200-220 ppm.
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In the case of vinylic substitution, internal bond rotation can result in the required syn-periplanar geometry necessary for β-hydride elimination to deliver the functionalized alkene product 37. A mixture of E/Z isomers is obtained due to the formation of a palladium enolate species (38), which facilitates reinsertion without facial preference. In the conjugate addition case, intermediate 34 can be intercepted with formic acid to form a palladium complex (35) that can readily undergo reductive cleavage to form the new C–H bond. Control experiments run with added Heck product have ruled out the occurrence of a tandem Mizoroki–Heck reaction followed by reduction of the alkene by a palladium–hydride species; furthermore, computational studies suggest that reductive cleavage of Pd (rather than protonolysis) results in the formation of the product. Building on Cacchi’s original conditions, Minnaard and coworkers have introduced systems that do not require the addition of formic acid or tributylamine additives.
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