- Acidic ionic liquid based UiO-67 type MOFs: A stable and efficient heterogeneous catalyst for esterification
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A facile strategy for the synthesis of acidic ionic liquid based UiO-67 type MOFs was developed in this study. Br?nsted acids (H2SO4, CF3SO3H and hifpOSO3H (hexafluoroisopropyl sulfuric acid)) were introduced into UiO-67-bpy (bpy = 2,2′-bipyridine-5,5′-dicarboxylic acid) frameworks by reacting with bipyridyl nitrogen to introduce the properties of an acidic ionic liquid into the frameworks. The prepared catalysts, denoted as UiO-67-HSO4, UiO-67-CF3SO3 and UiO-67-hifpOSO3, were characterized by XRD, SEM, FT-IR, EA, TGA and N2 adsorption-desorption studies. The relatively high surface area was still maintained and acidic active groups were uniformly dispersed in the frameworks. The catalytic performance of UiO-67-HSO4, UiO-67-CF3SO3 and UiO-67-hifpOSO3 was evaluated by the esterification of acetic acid with isooctyl alcohol. The prepared catalysts showed good catalytic activities in the esterification, of which UiO-67-CF3SO3 gave the maximum isooctyl alcohol conversion of 98.6% under optimized conditions. The catalyst could be reused five times without a significant decrease in the conversion of isooctyl alcohol, and almost no active species were leached, indicating the excellent stability and reusability of the catalyst. Our study provides one effective way to synthesize heterogeneous acidic ionic liquid catalysts consisting of isolated, well defined acidic groups that will probably attract interest in acid catalyst chemistry.
- Xu, Zichen,Zhao, Guoying,Ullah, Latif,Wang, Meng,Wang, Aoyun,Zhang, Yanqiang,Zhang, Suojiang
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p. 10009 - 10016
(2018/03/23)
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- Alkyl Formate Ester Synthesis by a Fungal Baeyer–Villiger Monooxygenase
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We investigated Baeyer–Villiger monooxygenase (BVMO)-mediated synthesis of alkyl formate esters, which are important flavor and fragrance products. A recombinant fungal BVMO from Aspergillus flavus was found to transform a selection of aliphatic aldehydes into alkyl formates with high regioselectivity. Near complete conversion of 10 mm octanal was achieved within 8 h with a regiomeric excess of ～80 %. Substrate concentration was found to affect specific activity and regioselectivity of the BVMO, as well as the rate of product autohydrolysis to the primary alcohol. More than 80 % conversion of 50 mm octanal was reached after 72 h (TTN nearly 20 000). Biotransformation on a 200 mL scale under unoptimized conditions gave a space-time yield (STY) of 4.2 g L?1 d?1 (3.4 g L?1 d?1 extracted product).
- Ferroni, Felix Martin,Tolmie, Carmien,Smit, Martha Sophia,Opperman, Diederik Johannes
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p. 515 - 517
(2017/03/22)
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- MONOMER, POLYMER, RESIST COMPOSITION, AND PATTERNING PROCESS
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A polymer comprising recurring units derived from a (meth)acrylate monomer of tertiary ester type having branched alkyl on alicycle is used to form a resist composition. When subjected to exposure, PEB and organic solvent development, the resist composition is improved in dissolution contrast.
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- Hydroxide-promoted selective C(α)-C(β) bond activation of aliphatic ethers by rhodium(III) porphyrins
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The selective aliphatic C(α)-C(β) bond activation (CCA) of ethers by rhodium(III) porphyrin halides in the presence of KOH was achieved to give Rh-C(β) alkyls up to 88% yield. The addition of H2O and a phase transfer agent Ph4PBr improved the homogeneity of the reaction mixture and significantly brought down the reaction temperature to 60 °C. At this mild temperature, the C(α) co-product was oxidized to the corresponding esters in up to 89% yield. KOH promotes the bond activation by transferring the hydroxyl group to rhodium porphyrin to generate the key intermediate RhIII(ttp)OH (ttp = 5,10,15,20-tetratolylporphyrinate dianion).
- Lee, Siu Yin,Lai, Tsz Ho,Hui, Ying Ying,Chan, Kin Shing
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- Nickel-catalyzed hydrosilylation of CO2 in the Presence of Et3B for the synthesis of formic acid and related formates
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The reaction of CO2 with Et3SiH catalyzed by the nickel complex [(dippe)Ni(μ-H)]2 (1) afforded the reduction products Et3SiOCH2OSiEt3 (12%), Et 3SiOCH3 (3%), and CO, which were characterized by standard spectroscopic methods. Part of the generated CO was found as the complex [(dippe)Ni(CO)]2 (2), which was characterized by single-crystal X-ray diffraction. When the same reaction was carried out in the presence of a Lewis acid, such as Et3B, the hydrosilylation of CO2 efficiently proceeded to give the silyl formate (Et3SiOC(O)H) in high yields (85-89%), at 80 C for 1 h. Further reactivity of the silyl formate to yield formic acid, formamides, and alkyl formates was also investigated.
- Gonzalez-Sebastian, Lucero,Flores-Alamo, Marcos,Garcia, Juventino J.
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p. 7186 - 7194
(2014/01/06)
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- 2-(Sulfooxy)propane-1,2,3-tricarboxylic acid as novel and versatile catalyst for the formylation of alcohols and amines using ethyl formate under neat conditions
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2-(Sulfooxy)propane-1,2,3-tricarboxylic acid (supported on silica gel) has been introduced as novel and green catalyst for the formylation of alcohols and amines with ethyl formate, as mild formylation agent, under neat conditions at room temperature.. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
- Ghorbani-Choghamarani, Arash,Akbaripanah, Ziba
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experimental part
p. 450 - 453
(2012/06/04)
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- Room-temperature selective aliphatic carbon-carbon bond activation and functionalization of ethers by rhodium(II) porphyrin
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Selective aliphatic carbon(α)-carbon(β) bond activation of ethers by (5,10,15,20-tetramesitylporphyrinato)rhodium(II) (Rh(tmp) (1)) was achieved at room temperature to yield corresponding rhodium porphyrin alkyls and the functionalized esters. Rh(tmp)OH was the proposed intermediate responsible for cleaving the C(α)-C(β) bond. The reaction is general for both straight- and branch-chain ethers.
- Lee, Siu Yin,Lai, Tsz Ho,Choi, Kwong Shing,Chan, Kin Shing
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scheme or table
p. 3691 - 3693
(2011/09/20)
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- Hypervalent λ3-bromane strategy for Baeyer-Villiger oxidation: Selective transformation of primary aliphatic and aromatic aldehydes to formates, which is missing in the classical Baeyer-Villiger oxidation
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A conceptually distinct, modern strategy for Baeyer-Villiger oxidation (BVO) was developed. Our novel method involves initial hydration of water to carbonyl compounds, followed by ligand exchange of hypervalent aryl-λ3-bromane on bromane(III) with the resulting hydrate, yielding a new type of activated Criegee intermediate. The intermediate undergoes BV rearrangement and produces an ester via facile reductive elimination of an aryl-λ3-bromanyl group, because of the hypernucleofugality. The novel strategy makes it possible to induce selectively the BV rearrangement of straight chain primary aliphatic as well as aromatic aldehydes, which is missing in the classical BVO: for instance, octanal and benzaldehyde afforded rearranged formate esters with high selectivity (>95%) under our conditions, while the attempted classical BVO produced only carboxylic acids. This firmly establishes the powerful nature of new methodology for BVO.
- Ochiai, Masahito,Yoshimura, Akira,Miyamoto, Kazunori,Hayashi, Satoko,Nakanishi, Waro
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supporting information; experimental part
p. 9236 - 9239
(2010/11/02)
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- Dual behavior of alcohols in iodine-catalyzed esterification under solvent-free reaction conditions
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The dual behavior phenomenon of alcohols in iodine-catalyzed esterification under solvent-free reaction conditions (SFRCs) is described; the governing factor is the stability of the carbonium ion generated from the alcohol; high concentration reaction conditions (HCRCs) or dilute solutions are much less suitable. In the case of benzylic alcohols, loss of optical activity was noted, whereas alkyl alcohols furnished a product with retention of stereochemistry.
- Jereb, Marjan,Vra?i?, Dejan,Zupan, Marko
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body text
p. 2347 - 2352
(2009/09/06)
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- Oxidative C-C bond cleavage of primary alcohols and vicinal diols catalyzed by H5PV2Mo10O40 by an electron transfer and oxygen transfer reaction mechanism
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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
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supporting information; scheme or table
p. 14474 - 14476
(2009/02/08)
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- Corona-induced photoxidation of alcohols and hydrocarbons over TiO 2 in the absence of a UV light source - A novel and environmentally friendly method for oxidation
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Corona-induced photooxidation is a novel oxidation methodology for the efficient oxidation of alcohols and hydrocarbons utilizing the advantage of both the high oxidizing power of ozone formed in the reactor as well as the photooxidation capability of the UV light generated during the corona discharge. The Royal Society of Chemistry 2005.
- Pillai, Unnikrishnan R.,Sahle-Demessie, Endalkachew
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p. 2256 - 2258
(2007/10/03)
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- Cerium polyoxometalate as a reusable catalyst for acetylation and formylation of alcohols
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Efficient esterification of primary and sterically-hindered secondary or tertiary alcohols with acetic anhydride was achieved in the presence of ammonium decatungestocerate(IV) icosahydrate, (NH4)8[CeW 10O36]·OH2O, as catalyst in high yields. Primary and secondary alcohols were also converted to their corresponding acetates and formates with acetic acid and ethyl formate in the presence of this catalyst. Easy work-up, non-toxicity, reusability, and stability of the catalyst are noteworthy advantages of this method. Springer-Verlag 2004.
- Mirkhani, Valiollah,Tangestaninejad, Shahram,Moghadam, Majid,Yadollahi, Bahram,Alipanah, Ladan
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p. 1257 - 1263
(2007/10/03)
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- Preparation of levulinic acid esters and formic acid esters from biomass and olefins; compositons prepared thereby; and uses of the compositions as fuel additives
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This invention relates to a process for producing a mixture of levulinic acid esters and formic acid esters from biomass and olefins, and the composition prepared therefrom. This invention also relates to usage of the mixture of these esters as fuel and as fuel additives for gasoline fuel, diesel fuel, and biofuel.
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- Novel catalytic acetylation and formylation of alcohols with potassium dodecatungstocobaltate trihydrate (K5CoW12O40·3H2O)
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Acetylation and formylation reactions of alcohols with ethyl acetate, acetic acid and ethyl formate were catalyzed with potassium dodecatungstocobaltate trihydrate (K5CoW12O40·3H2O) in a mild, efficient and convenient method with high to excellent yields.
- Habibi, Mohammad H,Tangestaninejad, Shahram,Mirkhani, Valiollah,Yadollahi, Bahram
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p. 8333 - 8337
(2007/10/03)
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- α,α-DICHLOROALDEHYDES AND α,α-DICHLOROCARBOXYLIC ACIDS FROM LONG CHAIN 1-ALKANOLS. IMPROVED CHLORINATION IN THE SYSTEM DMF-CHCl3-MgCl2
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Production of α,α-dichloroaldehydes by direct chlorination of 1-alkanols with chlorine gas, catalyzed by DMF and DMF*HCl, was extended to long chain compounds (CnH2n+1OH; n = 5, 6, 8, 10, 12, 14, 16, 18).Two problems specific to the longer chains were solved to obtain isolated yields in the range 70-85 percent; a) parasitic radical chlorination was largely controlled by shielding from light; b) alkyl alkanoate side product (8 percent for n = 8 but 25 percent for n = 16 or 18) was decreased to 0-2 percent in the presence of MgCl2*H2O.Homogeneity of the reaction medium was improved with chloroform as a cosolvent.Oxidation of the aldehydes to dichlorocarboxylic acids proceeded smoothly with aqueous KMnO4 up to the tetradecanal.For the longer chains 30 percent hydrogen peroxide-NaHCO3 in acetone (overnight at 48-52 deg C) was the preferred oxidant.
- Buyck, L. De,Casaert, F.,Lepeleire, C. De,Schamp, N.
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p. 525 - 534
(2007/10/02)
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- The preparation of esters of formic acid using boron oxide
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Boron oxide has been found to act as an efficient reagent in the preparation of a number of formate esters by the direct esterification of formic acid with the alcohol.The reaction is most appropriate for primary and secondery alcohols, including unsaturated alcohols.The formate ester so produced is free of contamination by unreacted alcohol.
- Carlson, Charles G.,Hall, Judith E.,Huang, Yan Y.,Kotila, Sirpa,Rauk, Arvi,Tavares, Donald F.
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p. 2461 - 2463
(2007/10/02)
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- One-Pot Conversion of Primary Alkyl Chlorides and Dichlorides into Alcohols, Diols, and Ethers via Formic Ester Intermediates under Phase-Transfer Conditions
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A procedure for the synthesis of alkyl formates, 1,ω-alkanediyl diformates, and unsaturated analogs from alkyl (or 2-alkenyl) halides and sodium formate under solid/liquid phase-transfer conditions is reported.For conversion into alcohols or diols, respectively, the formic esters can be directly hydrolyzed in the reaction mixture of their preparation.Using a related procedure, cyclic ethers are prepared from 1,ω-dichloroalkanes, sodium formate, and potassium hydroxide under solid/liquid phase-transfer conditions.
- Zahalka, Hayder A.,Sasson, Yoel
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p. 763 - 765
(2007/10/02)
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- Thermolyse en solution de t-butylperoxy-2 oxacyclanes
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The thermal decomposition of 2-tert-butylperoxytetrahydrofuran (1a), 2-tert-butylperoxytetrahydropyran (1b) and 2-tert-butylperoxyoxepan (1c) was studied in dibutyl phtalate.A free radical mechanism was suggested to explain the formation of the thermolysis products. The first step of this mechanism is the homolysis of the peroxidic bond.Two kinds of radicals are obtained: tert-butoxy (2) and oxacyclan-2-oxy (3a, b or c) radicals. When they have escaped out of the solvent cage, tert-butoxy radicals lead to the formation of tert-butanol (4), by transfer reactions to the solvent, and of acetone (5), by β-scission reactions. In the solvent cage, part of the oxacyclan-2-oxy radicals (3) give open alkyl radicals (3'): formyloxy-3-propyl (3'a), formyloxy-4-butyl (3'b) or formyloxy-5-pentyl (3'c) radicals, by β-scission reactions.About half of the radicals (3') diffuse out of the solvent cage, leading, after transfer to the solvent,the corresponding n-alkyl formates (6): n-propyl formate (6a), n-butyl formate (6b) or n-pentyl formate (6c). By coupling in the solvent cage of tert-butoxy and the remaining radicals (3'), 3-tert-butoxypropyl formate (6'a), 4-tert-butoxybutyl formate (6'b) or 5-tert-butoxypentyl formate (6'c) are obtained.Morover in the solvent cage, disproportionation reactions between tert-butoxy (2) and oxacyclan-2-oxy radicals (3) give the corresponding lactones (7): 4-butanolide (7a), 5-pentanolide (7b) or 6-hexanolide (7c). The balance of the products resulting from the behaviour of the oxacyclan-2-oxy (3) or the related formyloxy-n-alcyl (3') radical shows that about 50 percent of these radicals reacted before they had escaped out of the solvent cage.Thus, since the radicals issued from the thermolysis of 2-tert-butylperoxyoxacyclanes (1) undergo few interactions with the solvent in wich the decomposition take place, it appears that these cyclic peroxyketals act as rather poor free radical initiators.
- Maillard, Bernard,Manigand, Claude,Pavlovna Tarassova, Natalia,Villenave, Jean-Jacques,Filliatre, Claude
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p. 255 - 260
(2007/10/02)
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- JOINT HOMOLYTIC LIQUID-PHASE TRANSFORMATIONS OF ALKYL ORTHOFORMATES AND ACETALS
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The reaction kinetics and the reactivity of ethyl orthoformate were studied in joint transformations with 1,3-dioxane, 1,1-dialkoxyalkanes, and hexyl orthoformate, initiated by tert-butyl peroxide.It was established that the corresponding dialkyl carbonates and esters are formed as a result of specific radical-chain transformations.From the ratio of the products in the range 120-150 deg C it was determined that alkyl orthoformates are more reactive than linear and cyclic acetals.
- Kostyukevich, L. L.,Kalashnikov, S. M.,Pastushenko, E. V.,Zlot-skii, S. S.,Rakhmankulov, D. L.
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p. 1664 - 1666
(2007/10/02)
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- Products and mechanism of the reaction of ozone with acetals
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As a result of the ozonized oxidation of acetals at -20-60 deg C esters and alcohols (or glykol monoesters), hydroperoxides, and water accumulate in parallel in the initial period of the reaction.The formation of esters and alcohols is explained by molecular paths, and the formation of hydroperoxides and water is explained by radical paths; the yields of hydroperoxides and water can be reduced by reducing the ozonization temperature.The reactivity of acetals increases with increase in the size of the alkoxyl group.
- Brudnik, B. M.,Kuramshin, E. M.,Imashev, U. B.,Zlotskii, S. S.,Rakhmankulov, D. L.
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p. 608 - 614
(2007/10/02)
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- FREE-RADICAL LIQUID-PHASE FRAGMENTATION OF MIXED FORMALS
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The homolytic liquid-phase reactions of methoxyalkoxymethanes, initiated by the decomposition of tert-butyl peroxide, in the range of 120-150 deg C were investigated.The fragmentation of the formals occurs as an unbranched chain process, and the main products are the corresponding alkyl and methyl formates.A scheme is proposed which describes the formation of all the observed products from fragmentation of mixed formals.A comparison was made of tha ease of β- elimination of various primary alkyl radicals during the fragmentation of the methoxyalkoxymethyl radicals which form.The physicochemical constants were determined, and the 1H and 13C NMR spectra of the mixed formals were recorded.
- Kalashnikov, S. M.,Zlotskii, S. S.,Imashev, U. B.,Rakhmankulov, D. L.
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p. 1379 - 1382
(2007/10/02)
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