116-54-1Relevant articles and documents
TETRAHEDRAL INTERMEDIATES 4. THE EFFECT OF CHLORO-SUBSTITUENTS ON THE KINETICS OF THE BREAKDOWN OF HEMIORTHOESTERS
Capon, Brian,Dosunmu, Miranda I.
, p. 3625 - 3634 (1984)
2-Hydroxy-2-chloromethyl-1,3-dioxolane (4) and 2-hydroxy-2-dichloromethyl-1,3-dioxolane (5) have been detected as intermediates by 1H NMR spectroscopy in the hydration of respectively 2-chloromethylene-1,3-dioxolane and 2-dichloromethylene-1,3-dioxolane in aqueous acetonitrile.The kinetics of the breakdown of (4) and (5) into ethylene glycol monochloroacetate and monodichloroacetate have been studied by uv spectroscopy and values of kH(+), kHO(-), and kH2O evaluated.It was found that the introduction of chlorosubstituents into 2-hydroxy-2-methyl-1,3-dioxolane caused a decrease in kH(+) and increase in kHO(-) and little change in kH2O for its breakdown.The mechanisms of these reactions are discussed.
In situ derivatization/solid-phase microextraction for the determination of haloacetic acids in water
Sarrion,Santos,Galceran
, p. 4865 - 4873 (2000)
An in situ derivatization solid-phase microextraction method has been developed for the determination of haloacetic acids (HAAs) in water. The analytical procedure involves derivatization of HAAs to their methyl esters with dimethyl sulfate, headspace sampling using solid-phase microextraction (SPME), and gas chromatography-ion trap mass spectrometry (GC/ITMS) determination. Parameters affecting both derivatization efficiency and headspace SPME procedure, such as the selection of the SPME coating, derivatization-extraction time and temperature, and ionic strength, were optimized. The commercially available Carboxen-poly(dimethylsiloxane) (CAR-PDMS) fiber appears to be the most suitable for the determination of HAAs. Moreover, the formation of HAA methyl esters was dramatically improved (up to 90-fold) by the addition of tetrabutylammonium hydrogen sulfate (4.7 μmol) to the sample as ion-pairing agent in the derivatization step. The precision of the in situ derivatization/HS-SPME/GC/ITMS method evaluated using an internal standard gave relative standard deviations (RSDs) between 6.3 and 11.4%. The method was linear over 2 orders of magnitude, and detection limits were compound-dependent, but ranged from 10 to 450 ng/L. The method was compared with the EPA method 552.2 for the analysis of HAAs in various water samples, and good agreement was obtained. Consequently, in situ derivatization/HS-SPME/GC/ITMS is proposed for the analysis of HAAs in water.
Selective Photo-Oxygenation of Light Alkanes Using Iodine Oxides and Chloride
Liebov, Nichole S.,Goldberg, Jonathan M.,Boaz, Nicholas C.,Coutard, Nathan,Kalman, Steven E.,Zhuang, Thompson,Groves, John T.,Gunnoe, T. Brent
, p. 5045 - 5054 (2019/10/28)
Partial oxidation of light alkanes to generate alkyl esters has been achieved under photochemical conditions using mixtures of iodine oxides and chloride salts in trifluoroacetic acid (HTFA). The reactions are catalytic in chloride and are successful using compact fluorescent light, but higher yields are obtained using a mercury lamp. In this photo-initiated oxyesterification process, the robust alkyl ester products are resistant to over-oxidation, and under optimized conditions yields for alkyl ester production of ～50 % based on methane, ～60 % based on ethane (with a total functionalized yield of EtX (X=TFA or Cl) of 80 %) and ～30 % based on propane have been demonstrated. The reaction also proceeds in aqueous HTFA and dichloroacetic acid with lower yields. Mechanistic studies indicate that the process likely operates by a chlorine hydrogen atom abstraction pathway wherein alkyl radicals are generated, trapped by iodine, and converted to alkyl trifluoroacetates in situ.
Reactions of trialkyl phosphites with mono- and diacylals of halo-substituted acetic acids
Gazizov,Gaisin,Khairullin,Safina,Karimova,Petrova
, p. 1738 - 1741 (2007/10/03)
Trialkyl phosphites react with diacylals of di- and trichloroacetic acids by the pathway of the Perkow reaction; with monoacylals of bromo- and iodoacetic acids, by the pathway of the classical Arbuzov reaction; and with monoacylals of di- and trichloroacetic acids, by the pathway of the nonclassical Arbuzov reaction.
Reformatsky-type addition of esters of α-halogeno carboxylic acids to aldehydes and ketones in the presence of Fe(CO)5
Terent'ev,Vasil'eva,Kuz'mina,Mysov,Ikonnikov,Kuznetsov,Belokon'
, p. 1121 - 1127 (2007/10/03)
Reformatsky-type addition of esters of α-halogeno carboxylic acids to aldehydes and ketones in the presence of Fe(CO)5 and an activating agent (CBrCl3 or I2) afforded the corresponding esters of β-hydroxy acids in good yields. Possible reaction mechanisms are discussed.
Intramolecular Geminal and Vicinal Element Effects in Substitution of Simple Bromo(chloro)alkenes by Methoxide and Thiolate Ions. An Example of a Single Step Substitution?
Beit-Yannai, Michal,Rappoport, Zvi,Shainyan, Bagrat A.,Danilevich, Yuri S.
, p. 8049 - 8057 (2007/10/03)
Intramolecular element effects kBr/kCl for substitution of geminal bromochloroalkenes BrC(Cl)=C-(Br)Cl (1), BrC(Cl)=CCl2 (2), Me2C=C(Br)Cl (3), and XCH=C(Br)Cl (X = Cl, 4; X = Br, 5), with MeO- and RS- nucleophiles were investigated. 3 did not give substitution, and 4 and 5 gave substitution with MeO- via an initial elimination (to acetylene)-addition route, followed by further reactions. In reactions of 4 with thiolates, geminal element effects of 2-10 were obtained. Formation of RSC(Cl)=C(Cl)Y, Y = SR, Br, is ascribed to an initial halophilic reaction, followed by addition of RSCl to the formed acetylene. Reaction of 2 with MeO- gave a high vicinal element effect, and RS- gave a high geminal element effect. Reaction of 1 with both MeO- and RS- ions gave high (2 orders of magnitude) geminal element effects, which were interpreted as indicating a rate-determining C-X bond cleavage. This is supported by the high kBr/kCl intermolecular element effects (k(1)/k(Cl2C=CCl2) with MeO- and PhCH2S- ions. Mechanistic alternatives based on these observations are discussed.
Process for the reaction of a low-molecular hydroxyl compound with a carboxylic acid halide
-
, (2008/06/13)
In a process for reacting a low molecular weight hydroxy compound with a carboxylic acid halide, a small amount of the acid halide is introduced into the reaction vessel and the remainder of the acid halide and the hydroxy compound are added gradually in an approximately stoichiometric ratio. The hydrogen halide formed is thus prevented from dissolving in the reaction medium. The heat of reaction to be dissipated is negligible.
NUCLEOPHILIC REACTIONS AT A VINYLIC CENTER. XXVIII. FLUOROCHLOROETHENES AND FLUOROBROMOETHENES IN REACTIONS WITH SODIUM ALCOHOLATES AND ARENETHIOLATES
Shainyan, B. A.,Vereshchagin, A. L.
, p. 1981 - 1988 (2007/10/02)
During the reaction of halogenoethenes (Z+E)-CHX=CFX with sodium methoxide and with sodium p-thiocresolate in methanol initial attack by the nucleophilic takes place at the carbon atom attached to the fluorine atom.In the reactions with sodium methoxide the intermediate monosubstitution products are more reactive than the initial halogenoethenes, and the main reaction products are the ortho esters CHXYC(OMe)3.An "element effect", i.e., concurrent substitution of F and Cl(Br) in the reaction with sodium methoxide, was discovered.With sodium p-thiocresolate trifluorochloroethene gives the product from substitution of the chlorine atom and a small amount of the addition product as impurity.The other ethenes give substitution, addition, and halogenophilic reduction products and also the products from further transformations (hydrolysis and decarboxylation).
REACTION OF 1-(ACYLCARBAMOYL)-3,5,5-TRIMETHYL-2-PYRAZOLINES WITH NUCLEOPHILIC REAGENTS
Zobova, N. N.,Nazyrova, A. Z.
, p. 1906 - 1908 (2007/10/02)
1-(Acylcarbamoyl)-3,5,5-trimethyl-2-pyrazolines react with water and alcohols to form 3,5,5-trimethyl-4,5-dihydro-1H-pyrazole-1-carboxamide with the elimination of substituted carboxylic acids. 1-(Benzoylcarbamoyl)-3,5,5-trimethyl-2-pyrazoline and 3,5,5-trimethyl-4,5-dihydro-1H-pyrazole-1-carboxamide form 2:1 complexes with Cu(II) ions.
Ozonides of Acyclic Olefins Having Mono- and Dichloro-Substituted Double Bonds
Griesbaum, Karl,Schlindwein, Konrad,Hilss, Michael
, p. 1843 - 1848 (2007/10/02)
Ozonolyses of acyclic olefins containing 1,2-dichloro-substituted (4a,b) and monochloro-substituted double bonds (7a, b, 12) as well as two (4a, b, 7a, b) or one halomethyl group (12) attached to the double bond afford the corresponding ozonides as the first representatives of monocyclic chlorinated ozonides.Their stability decreases in order 5a, 5b > 8a, 8b > 13. - Key Words: Ozonides/ 1,2,4-Trioxolanes, 3-chloro-, 3,5-dichloro- / Polyethylene
