- Comparative Analysis of Electronic States of Saturated Dioxa and Dithia Heterocycles and Their Radical Cations
-
ESR spectra of the radical cations of 1,3-dioxa- and 1,3-dithiacyclopentanes and their 2-methylated derivatives were studied both experimentally and theoretically.The orbital interaction analysis based on the localized orbital indicates that the order of the two highest occupied molecular orbitals is reversed between the dioxa and the dithia systems.It is concluded that the reversal is caused by the interaction of the orbital localized on the methylene C-H bonds of carbon atom 2 with the "out of plane" lone-pair MO composed of the lone-pair orbitals on the oxygen and the sulfur atoms.The use of the usual canonical orbital and the internally consistent SCF orbital proposed by Davidson as the base is discussed comparatively.
- Momose, Takamasa,Tanimura, Ryuji,Ushida, Kinimori,Shida, Tadamasa
-
-
Read Online
- Biomass alcoholysis method for petroleum-based plastic POM
-
The invention discloses a biomass alcoholysis method for petroleum-based plastic POM. According to the method, simple biomass derivative alcohol and the petroleum-based plastic POM are allowed to generate a cyclic acetal product through dehydration condensation under catalytic conditions; low reaction cost and high added value are realized, and only water is byproduced and is easy to separate; and an obtained product has high added value, can be used for preparing organic solvents such as lignin and chromatographic analysis solvents, metal surface treatment agents or medical intermediates and monomers, realizes green, efficient and low-cost recovery, and has a high practical application value.
- -
-
Paragraph 0030-0051
(2021/05/01)
-
- Efficient Plastic Waste Recycling to Value-Added Products by Integrated Biomass Processing
-
The industrial production of polymeric materials is continuously increasing, but sustainable concepts directing towards a circular economy remain rather elusive. The present investigation focuses on the recycling of polyoxymethylene polymers, facilitated through combined catalytic processing of polymer waste and biomass-derived diols. The integrated concept enables the production of value-added cyclic acetals, which can flexibly function as solvents, fuel additives, pharmaceutical intermediates, and even monomeric materials for polymerization reactions. Based on this approach, an open-loop recycling of these waste materials can be envisaged in which the carbon content of the polymer waste is efficiently utilized as a C1 building block, paving the way to unprecedented possibilities within a circular economy of polyoxymethylene polymers.
- Beydoun, Kassem,Klankermayer, Jürgen
-
p. 488 - 492
(2020/01/24)
-
- Ruthenium-Catalyzed Synthesis of Cyclic and Linear Acetals by the Combined Utilization of CO2, H2, and Biomass Derived Diols
-
Herein a transition-metal catalyst system for the selective synthesis of cyclic and linear acetals from the combined utilization of carbon dioxide, molecular hydrogen, and biomass derived diols is presented. Detailed investigations on the substrate scope enabled the selectivity of the reaction to be largely guided and demonstrated the possibility of integrating a broad variety of substrate molecules. This approach allowed a change between the favored formation of cyclic acetals and linear acetals, originating from the bridging of two diols with a carbon-dioxide based methylene unit. This new synthesis option paves the way to novel fuels, solvents, or polymer building blocks, by the recently established “bio-hybrid” approach of integrating renewable energy, carbon dioxide, and biomass in a direct catalytic transformation.
- Beydoun, Kassem,Klankermayer, Jürgen
-
supporting information
p. 11412 - 11415
(2019/07/18)
-
- A method for preparing 1, 3 - oxa naphthenic (by machine translation)
-
The invention discloses a 1, 3 - oxa naphthenic preparation method, the method comprises: diol, poly formaldehyde in water and ionic liquid catalyst in the presence of a cyclization reaction, containing the reaction product of the compound; wherein said diol is ethylene glycol or diethylene glycol; when the diol is ethylene glycol when, the target compound is 1, 3 - dioxolo; when the diol is diethylene glycol when, the target compound is 1, 3, 6 - heterocyclic octane; the ionic liquid catalyst comprises a cation and anion, the cation is selected from the isoquinoline kind of positive ion, quinoline kind of positive ion and benzimidazole in at least one of the kind of positive ion. The method of the invention the kind of positive ion cation is isoquinoline, quinoline kind of positive ion or benzimidazole kind of positive ion of the ionic liquid as catalyst to prepare 1, 3 - oxa naphthenic, mild reaction conditions, high product yield, catalyst is environment-friendly. (by machine translation)
- -
-
Paragraph 0085; 0086-0090
(2019/05/16)
-
- Photocatalytic Synthesis of 1,3-Dioxacyclanes from Diols and Primary Alcohols Effected by a System FeCl3–NaNO2/O2(Air)
-
Diols and primary alcohols were subjected to the action of a system FeCl3–NaNO2/O2 (air) under mercury lamp irradiation to synthesize unsubstituted and 2-methyl-1,3-dioxacyclanes: 1,3-dioxolane, 1,3-dioxepane, 1,3-dioxocane, 2-methyl-1,3-dioxolane, 2-methyl-1,3-dioxepane, 2-methyl-1,3-dioxocane. The probable mechanism of the photocatalytic synthesis of 1,3-dioxacyclanes was described by an example of 2-methyl-1,3-dioxolane.
- Makhmutov
-
p. 1710 - 1714
(2019/02/14)
-
- Preparation method of cyclic acetal
-
The invention discloses a preparation method of cyclic acetal. The method is characterized in that long-chain polyhydroxy compounds and small-molecular aldehydes are used as the substrates, long-chain weak-polarity molecules are used as the solvent, and the aldehydes are condensed with the hydroxyl groups at two ends of the polyhydroxy compounds under the effect of a catalyst to form the intramolecular cyclic acetal. Compared with a traditional acetal preparation method, the method has the advantages that the property differences of the solvent, reactants and the substrates are utilized to allow the aldehydes to be easy to react with the hydroxyl groups, and the cyclic acetal proportion in the product is high; the conversion rate of the aldehyde compounds reaches above 80%, and the selectivity of the cyclic acetal can reach above 80%.
- -
-
Paragraph 0028; 0029; 0030; 0031; 0032; 0033; 0035
(2017/08/29)
-
- Preparation method of 1,3-dioxolane
-
The invention discloses a preparation method of 1,3-dioxolane. The preparation method comprises the steps of carrying out a reaction by taking ethylene glycol and polyformaldehyde as raw materials and adding right amount of N86 type ionic liquid catalyst; drying the obtained product with solid caustic soda, rectifying, adding right amount of antioxidant and evenly mixing to obtain the target product 1,3-dioxolane. The preparation method has the advantages of being less in consumption of the catalyst, short in reaction time, low in reaction temperature, high in product purity, and the like.
- -
-
Paragraph 0016; 0017; 0018; 0019; 0020; 0021; 0022-0045
(2017/08/29)
-
- PROCESS FOR REMOVING FORMALDEHYDE FROM A COMPOSITION COMPRISING GLYCOLALDHEDYDE
-
A process for reducing the percentage by weight of formaldehyde present in a composition comprising glycolaldehyde, wherein formaldehyde is transformed into one or more formaldehyde acetal(s) and removed from the reactive distillation reaction solution by reactive distillation in the presence of at least one alcohol and a catalyst.
- -
-
Page/Page column 15
(2014/09/16)
-
- Reactions of cyclic boric acids esters with paraformaldehyde
-
Reactions of five- and six-membered cyclic esters of boric acids with paraformaldehyde lead to the corresponding 1,3-dioxacycloalkanes. It is shown that trans-isomers of 2,4,5-substituted 1,3,2-dioxaborinanes react faster than their cis-isomers.
- Brusilovskii, Yu. E.,Kuznetsov
-
experimental part
p. 542 - 544
(2011/06/22)
-
- Oxidative C-C bond cleavage of primary alcohols and vicinal diols catalyzed by H5PV2Mo10O40 by an electron transfer and oxygen transfer reaction mechanism
-
Primary alcohols such as 1-butanol were oxidized by the H5PV2Mo10O40 polyoxometalate in an atypical manner. Instead of C-H bond activation leading to the formation of butanal and butanoic acid, C-C bond cleavage took place leading to the formation of propanal and formaldehyde as initial products. The latter reacted with the excess 1-butanol present to yield butylformate and butylpropanate in additional oxidative transformations. Kinetic studies including measurement of kinetic isotope effects, labeling studies with 18O labeled H5PV2Mo10O40, and observation of a prerate determining step intermediate by 13C NMR leads to the formulation of a reaction mechanism based on electron transfer from the substrate to the polyoxometalate and oxygen transfer from the reduced polyoxometalate to the organic substrate. It was also shown that vicinal diols such as 1,2-ethanediol apparently react by a similar reaction mechanism. Copyright
- Khenkin, Alexander M.,Neumann, Ronny
-
supporting information; experimental part
p. 14474 - 14476
(2009/02/08)
-
- Functionalized heterocycles as modulators of chemokine receptor function and methods of use therefor
-
Disclosed are novel compounds having the formula or a physiologically acceptable salt, amide, ester or prodrug thereof. The compounds can be used to modulate (antagonize, agonize) chemokine receptor function. Also disclosed is a method for treating a patient having an inflammatory disease and/or viral infection comprising administering an effective amount of a compound of Formula I. In particular embodiments, the invention is a method for treating a patient infected with HIV.
- -
-
-
- 2-methoxyimino-2-(pyridinyloxymethyl) phenyl acetamides with substituted ketal derivatives on the pyridine ring
-
The present invention provides novel 2-methoxyimino-2-(pyridinyloxymethyl)phenyl acetamide compounds with substituted ketal substituents on the pyridine ring, their use as fungicidal compounds, and their use in fungicidal compositions comprising at least one of the 2-methoxyimino-2-(pyridinyloxymethyl)phenyl acetamide compounds as the active ingredient.
- -
-
-
- Anthranilic acid derivatives as multi drug resistance modulators
-
Anthranilic acids of formula (I): wherein each of R to R9is an organic substituent, n is 0 or 1, m is 0 or an integer of 1 to 6, q is 0 or 1, X is a direct bond, O, S, —S—(CH2)por —O—(CHO2)p— wherein p is from 1 to 6 and Ar is an unsaturated carbocyclic or heterocyclic group, and the pharmaceutically acceptable salts thereof, have activity as inhibitors of P-glycoprotein and may thus be used, inter alia, as modulators of multidrug resistance in the treatment of multidrug resistant cancers, for example to potentiate the cytotoxicity of a cancer drug.
- -
-
-
- A novel cyclic formal, 1,3,5,7-tetraoxacyclononane, from the direct reaction of 1,3,5-trioxane and ethylene oxide
-
A new reaction between 1,3,5-trioxane and ethylene oxide has been observed and a novel cyclic formal, which is the reaction product of 1 equiv. of 1,3,5-trioxane and 1 equiv. of ethylene oxide, has been isolated and identified.
- Masamoto,Yamasaki,Sakai,Itoh,Tsutsumi,Nagahara
-
p. 1809 - 1810
(2007/10/03)
-
- Identification of 1,3-dioxanes and 1,3-dioxolanes as malodorous compounds at trace levels in river water, groundwater, and tap water
-
A study of organic compounds imparting odor problems in river waters and groundwaters has been conducted. The Tordera aquifer located in Barcelona and Girona (NE Spain) is the water supply reserve for many seasonally crowded villages on the coast. Closed loop stripping analysis (CLSA) and flavor profile analysis (FPA) have been employed as analytical tools to identify the compounds responsible for the odor complaints. The feasibility of purge-and- trap (P and T) has also been evaluated. The 2-alkyl-5,5-dimethyl-1,3-dioxanes and 2-alkyl-4-methyl-1,3-dioxolanes were the most significant compounds identified in river water and groundwater with a threshold odor of 10 ng/L for 2-ethyl-5,5-dimethyl-1,3-dioxane (2EDD), the most malodorous compound. The analyses were carried out by HRGC/MS, and the synthesized 1,3-dioxanes and dioxolanes were characterized by CI-MS and EI-MS/MS techniques. A company, currently manufacturing saturated and unsaturated polyester resins, located in the upper course of the river, produced these compounds as byproducts during the synthesis of resins. The pollution by dioxanes and dioxolanes affected all the aquifer and slowly diminished to the ppt levels when the company was forced to correctly treat their wastewaters. Additional examples of the presence of dioxanes and dioxolanes in wastewaters of other resin plants and also tap water of Barcelona are shown. A study of organic compounds imparting odor problems in river waters and groundwaters has been conducted. The Tordera aquifer located in Barcelona and Girona (NE Spain) is the water supply reserve for many seasonally crowded villages on the coast. Closed loop stripping analysis (CLSA) and flavor profile analysis (FPA) have been employed as analytical tools to identify the compounds responsible for the odor complaints. The feasibility of purge-and-trap (P&T) has also been evaluated. The 2-alkyl-5,5-dimethyl-1,3-dioxanes and 2-alkyl-4-methyl-1,3-dioxolanes were the most significant compounds identified in river water and groundwater with a threshold odor of 10 ng/L for 2-ethyl-5,5-dimethyl-1,3-dioxane (2EDD), the most malodorous compound. The analyses were carried out by HRGC/MS, and the synthesized 1,3-dioxanes and dioxolanes were characterized by CI-MS and EI-MS/MS techniques. A company, currently manufacturing saturated and unsaturated polyester resins, located in the upper course of the river, produced these compounds as byproducts during the synthesis of resins. The pollution by dioxanes and dioxolanes affected all the aquifer and slowly diminished to the ppt levels when the company was forced to correctly treat their wastewaters. Additional examples of the presence of dioxanes and dioxolanes in wastewaters of other resin plants and also tap water of Barcelona are shown.
- Romero, Jordi,Ventura, Francesc,Caixach, Josep,Rivera, Josep,Gode, Llui Xavier,Ninerola, Josep Ma.
-
p. 206 - 216
(2007/10/03)
-
- Prostaglandin analogs
-
Thromboxane receptor antagonist activity is exhibited by compounds of the formula STR1 wherein: V is --(CH 2) m --, --O--, or STR2 but if V is --O--or STR3 R 3 and R 4 must complete an aromatic ring; W is --(CH 2) 2 --, --CH CH-- or phenylene;X is a single bond, --CH CH--, --(CH 2) n --, or --O--(CH 2) n --; or X is branched alkylene or --O--branched alkylene wherein W is linked to Y through a chain n carbon atoms long;Y is --CO 2 H, --CO 2 alkyl, --CO 2 alkali metal, --CH 2 OH, --CONHSO 2 R 5, --CONHR 6, or --CH 2 -5-tetrazolyl;Z is O or NH;R 3 and R 4 are each independently hydrogen or alkyl or R 3 and R 4 together complete a ring optionally substituted through a ring carbon with a halo, lower alkyl, phenyl, halo (lower alkyl), halophenyl, oxo or hydroxyl group; and the remaining symbols are as defined in the specification.
- -
-
-
- Inclusion of Dioxolane by a Tricyclic Diol Host: Structure and Kinetics
-
The structure of the inclusion compound formed between trans-9,10-dihydroxy-9,10-diphenyl-9,10-dihydroanthracene (DDDA) and 1,3-dioxolane has been elucidated and its kinetics of enclathration and decomposition investigated.
- Caira, Mino R.,Coetzee, Anita,Nassimbeni, Luigi R.,Toda, Fumio
-
p. 1565 - 1578
(2007/10/03)
-
- Kinetic Patterns of Formation and Hydrolysis of 1,3-Dioxolane in Aqueous Solutions under Catalysis by p-Toluenesulfonic Acid
-
The preparation of 1,3-dioxolane in aqueous-ethylene glycol solutions of formaldehyde was studied. The dependences of the rate constants on temperature, catalyst concentration, and water content in the system were determined. A mathematical model of the process is suggested.
- Balashov,Danov,Chubarov
-
p. 1276 - 1280
(2007/10/03)
-
- Anti-fungal agents
-
A compound having the formula STR1 which is an anti-fungal agent is described. The producing organism Colletotricum accutatum is also described, along with a method of production.
- -
-
-
- Liquid-phase Oxidation of 1,2-Ethane Diol
-
The oxidation rate and the kind of oxidation products in the reaction of 1,2-ethane diol (1) with molecular oxygen in liquid phase at 150 deg C were investigated. 1 has a very low oxidation rate.Cu-, Zn-, Fe-, Co- and Al-acetylacetonates as catalysts increase the reaction rate.The main-products of the investigated reaction are the 1,3-dioxolan (2), the 2-methyl-1,3-dioxolan (3) and the 2-methylol-1,3-dioxolan (4).The formation of formic and acetic acids and of the 1,3-dioxolanes is proved by GC, DC and HPLC.
- Schnurpfeil, D.,Maurer, G.
-
p. 307 - 310
(2007/10/02)
-
- Percutaneous absorption enhancers, compositions containing same and method of use
-
Novel 1,3-dioxolanes (1,3-dioxyacyclopentanes) are provided along with new 1,3-dioxolanes (1,3-dioxacyclopentanes) compositions which are useful in enhancing the absorption of therapeutic agents through the skin of humans and animals. The method for enhancing skin penetration of therapeutic agents using 1,3-dioxacycloalkanes is also described. The preferred compounds are 1,3-dioxolanes (1,3-dioxacyclopentanes) and 1,3-dioxanes (1,3-dioxacyclohexanes). The preferred compounds have the formula: STR1 wherein R, R0, R1, R2, R3, R4, R5 and R6 are each independently selected from hydrogen and C1 to C18 aliphatic groups, preferably alkyl, alkenyl, and the halo, hydroxy, carboxy, carboxamide and carboalkoxy substituted forms thereof, with at least one of said R's an alkyl or alkenyl group of C4 to C18 and n=0 or 1; the total number of carbon atoms in all of said R groups being no more than 40, and preferably less than 20 and not more than 1 thereof containing 18 or more carbon atoms.
- -
-
-
- CH3OCH.+, a New Stable C2H4O.+ Isomer, and a Reassessment of the Oxirane.+ Potential Surface
-
The .+ isomer of structure .+ has been shown to be unambiguously generated by CO2 loss from ionized methyl glyoxylate. ΔHf0 for this new ion was measured to be 224 +/- 1 kcal mol-1.The .+ ion produced by the loss of CH2O from ionized 1,3-dioxolane and by the loss of HCOOH from ionized methoxymethyl formate was proposed to have the structure .+, ΔHf0 = 206 +/- 2 kcal mol-1.Ionized oxirane in either its 2B1 or 2A1 state was proposed to be generated by loss of CO2 from ionized ethylene carbonate at a threshold energy corresponding to a ΔHf0 = 235 +/- 1 kcal mol-1.The structure assignments were aided by observations of collisional activation and metastable ion mass spectra.The common fragmentations of .+ and .+ ions, loss of CH3. and H., take place at similar high internal energies, leading to large kinetic energy releases in the metastable ion decompositions.Interpretations of the observations were in keeping with recent high-level ab initio molecular orbital theory calculations, but detailed mechanisms could not be established.
- Buschek, J. M.,Holmes, J. L.,Terlouw, J. K.
-
p. 7321 - 7325
(2007/10/02)
-
- Novel polyol ether compounds, process preparing the compounds, and cosmetics comprising same
-
Triglycerine monoalkyl ethers of the general formula (I), which are novel polyol ether compounds, STR1 in which R represents a saturated or unsaturated, linear or branched fatty hydrocarbon group having from 8 to 24 carbon atoms. The ethers (I) of the present invention are prepared from firstly subjecting 1,3-bis-o-(2,3-o-isopropylideneglyceryl)glycerine (II) and an etherifying agent (IV) to Williamson's ether synthesis reaction, and the resulting 1,3-bis-o-(2,3-o-isopropylideneglyceryl)-2-o-alkylglycerine (III) is subsequently subjected to hydrolysis. The ethers according to the invention are chemically stable because no linkages susceptible to decomposition, e.g. ester bond, are contained in the molecular structure of the ethers. Moreover, the ethers give a reduced degree of stimulus to the skin and have the surface activity, so that they are useful as an emulsifier, oil (emolient), humectant, thickener and particularly as a component of cosmetics.
- -
-
-
- TRANSFORMATIONS OF CYCLIC ORTHO MONO- AND DIESTERS BY THE ACTION OF FREE RADICALS IN THE LIQUID PHASE
-
The homolytic liquid-phase reactions of 2-propoxy-1,3-dioxane, 1,2-di(1,3-dioxolan-2-yloxy)ethane, and 1,3-di(1,3-dioxan-2-yloxy)propane, initiated by tert-butoxyl radicals, were investigated.A mechanism is proposed for the formation of dipropylcarbonate, 1,3-dioxan-2-one, propylformate, propionaldehyde, and propane from 2-propoxy-1,3-dioxane.The kinetic parameters characterizing the rate and direction of the transformations were determined.It was found that the corresponding linear and cyclic carbonates are mainly formed from the ortho diesters.
- Kostyukevich, L. L.,Pastuschenko, E. V.,Zlot-skii S. S.,Rakhmankulov, D. L.
-
p. 127 - 132
(2007/10/02)
-
- Rational Mechanism for Homogeneous Hydrogenation of Carbon Monoxide to Alcohols, Polyols, and Esters
-
The products derived from synthesis gas conversion by homogeneous catalysis are concluded to be formed via the key intermediate formaldehyde.The intermediacy of formaldehyde is supported by reaction rate studies, comparison reactions of formaldehyde with synthesis gas, and the trapping of formaldehyde and glycolaldehyde intermediates during a reaction as their ethylene glycol acetals.Although the formation of formaldehyde from synthesis gas is themodynamically unfavorable, it is argued that the concentration of formaldehyde permitted by thermodynamics is more than sufficient for a transient intermediate.The overall mechanism incorporates only step that are already well established in the science of homogeneous catalysis.
- Fahey, Darryl R.
-
p. 136 - 141
(2007/10/02)
-
- Spasmolytics
-
Tertiary amines of formula 3 have a strong and prolonged spasmolytic effect, also after oral administration, on the smooth musculature of the tractus gastrointestinalis, the tractus urogenitalis and the bronchial system and have a low toxicity. The compounds can be synthetized according to methods known per se and been formulated to pharmaceutical compositions.
- -
-
-
