- Odorant-binding proteins and olfactory coding in the solitary bee Osmia cornuta
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Solitary bees are major pollinators but their chemical communication system has been poorly studied. We investigated olfactory coding in Osmia cornuta from two perspectives, chemical and biochemical. We identified (E)-geranyl acetone and 2-hexyl-1,3-dioxolane, specifically secreted by females and males, respectively. A transcriptome analysis of antennae revealed 48 ORs (olfactory receptors), six OBPs (odorant-binding proteins), five CSPs (chemosensory proteins), and a single SNMP (sensory neuron membrane protein). The numbers of ORs and OBPs are much lower than in the honeybee, in particular, C-minus OBPs are lacking in the antennae of O. cornuta. We have expressed all six OBPs of O. cornuta and studied their binding specificities. The best ligands are common terpene plant odorants and both volatiles produced by the bee and identified in this work.
- Yin, Xue-Wei,Iovinella, Immacolata,Marangoni, Roberto,Cattonaro, Federica,Flamini, Guido,Sagona, Simona,Zhang, Long,Pelosi, Paolo,Felicioli, Antonio
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Read Online
- Tunable catalysts for solvent-free biphasic systems: Pickering interfacial catalysts over amphiphilic silica nanoparticles
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Stabilization of oil/oil Pickering emulsions using robust and recyclable catalytic amphiphilic silica nanoparticles bearing alkyl and propylsulfonic acid groups allows fast and efficient solvent-free acetalization of immiscible long-chain fatty aldehydes with ethylene glycol.
- Zhou, Wen-Juan,Fang, Lin,Fan, Zhaoyu,Albela, Belén,Bonneviot, Laurent,De Campo, Floryan,Pera-Titus, Marc,Clacens, Jean-Marc
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Read Online
- Microwave promoted acetalization of aldehydes and ketones
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Aldehydes and ketones are readily acetalized under microwave irradiation with ethylene glycol in the presence of p-toluenesulfonic acid(PTSA), ferric(III) chloride or acidic alumina.
- Moghaddam,Sharifi
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- Phosphine-ligated Ir(III)-complex as a bi-functional catalyst for one-pot tandem hydroformylation-acetalization
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The complexation of IrCl3?3H2O with the electron-deficient phosphines (L1-L6) respectively afforded a bi-functional catalyst possessing the dual functions of transition metal complex (IrIII-P) and IrIII-Lewis acid for tandem hydroformylation-acetalization of olefins. The best result was obtained over L5-based IrCl3?3H2O catalytic system which corresponded to 97% conversion of 1-hexene along with 92% selectivity to the target acetals free of any additive. The crystal structure of the novel IrIII-complex of IrIII-L4 indicated that the electron-deficient nature of the involved phosphine warranted Ir-center in +3 valence state without reduction, which served as the Lewis acid catalyst for the subsequent acetalization of the aldehydes as well. Moreover, as an ionic phosphine, L6-based IrCl3?3H2O system immobilized in RTIL of [Bmim]PF6 could be recycled for 6 runs without the obvious activity loss or metal leaching.
- Liu, Huan,Liu, Lei,Guo, Wen-Di,Lu, Yong,Zhao, Xiao-Li,Liu, Ye
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p. 215 - 221
(2019/04/17)
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- Acetalization of aldehydes and ketones over H4[SiW 12O40] and H4[SiW12O 40]/SiO2
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H4[SiW12O40] (H-SiW12) is demonstrated to be able to efficiently catalyze the acetalization of aldehydes and ketones with ethylene glycol and 1,3-propanediol. Nevertheless, the possible leaching and the recycling of H-SiW12 are two major disadvantages that largely restrict its further application in industry. Moreover, H 4[SiW12O40] tends to deactivate strong proton sites due to the small surface area of 10 m2 g-1. Due to interactions with surface silanol groups, the proton sites of polyoxometalates (POMs) on SiO2 are less susceptible to deactivation. As such, immobilization of H4[SiW12O40] onto SiO 2 leads to the heterogeneous catalyst H4[SiW 12O40]/SiO2 (H-SiW12/SiO 2), which can catalyze the acetalization of aldehydes and ketones with ethylene glycol and 1,3-propanediol selectively and efficiently without the need of a drying agent. The acetalization process can proceed smoothly at a relatively low temperature under solvent-free conditions. The catalyst of H 4[SiW12O40]/SiO2 can be recycled at least ten times without an obvious decrease in its catalytic activity. As far as we know, the TONs of the H-SiW12/SiO2-catalyzed acetalization of cyclohexanone with ethylene glycol, and benzaldehyde with 1,3-propanediol are the highest reported so far.
- Zhao, Shen,Jia, Yueqing,Song, Yu-Fei
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p. 2618 - 2625
(2014/07/22)
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- Driving an equilibrium acetalization to completion in the presence of water
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Formation of an acetal from a carbonyl substrate by condensation with an alcohol is a classical reversible equilibrium reaction in which the water formed must be removed to drive the reaction to completion. A new method has been developed for acetalization of carbonyl substrates by diols in the presence of water. Complexation of poly(4-styrenesulfonic acid) with poly(4-vinylpyridine) generates a catalytic membrane of polymeric acid at the interface between two parallel laminar flows in a microchannel of a microflow reactor. The catalytic membrane provides a permeable barrier between the organic layer and water-containing layer in the reaction, and permits discharge of water to the outlet of the microreactor to complete the acetalization. Condensation of a variety of carbonyl substrates with diols proceeded in the presence of water in the microflow device to give the corresponding acetals in yields of up to 97% for residence times of 19 to 38 s. the Partner Organisations 2014.
- Minakawa, Maki,Yamada, Yoichi M. A.,Uozumi, Yasuhiro
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p. 36864 - 36867
(2014/11/08)
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- Mesoporous sulfated zirconia mediated acetalization reactions
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A novel, convenient, one step synthetic procedure for the synthesis of mesoporous sulfated zirconia (m-SZ) using zirconium carbonate complex and its use as solid acid catalyst for the acetalization of different carbonyl compound is reported. The high specific BET surface area (234 m2 g -1) of m-SZ is achieved after the removal of the surfactant (cetyltrymethylammonium bromide, CTAB) through calcination at 550 °C for 6 h. Microscopic analysis indicated the presence of spherical particles with worm like pores. DRIFT (diffuse reflectance FTIR) of pyridine adsorbed m-SZ and NH3-TPD (temperature programmed desorption) analysis suggested the presence of appreciable amount of Bro?nsted acid sites. The synthesized m-SZ showed high catalytic activity towards protection of carbonyl compounds through acetal/ketal formation. For the open ketal (from cyclohexanone and methanol) 97% conversion with 100% selectivity was obtained in 1 h at room temperature under solvent free condition. The catalyst can be easily recycled after separation from the reaction system without considerable loss in catalytic activity.
- Sinhamahapatra, Apurba,Sutradhar, Narottom,Ghosh, Malay,Bajaj, Hari C.,Panda, Asit B.
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experimental part
p. 87 - 93
(2012/04/10)
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- Highly efficient and chemoselective acetalization of carbonyl compounds catalyzed by new and reusab e zirconyl triflate, zr0(0tf)2
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Various types of aromatic aldehydes were efficiently converted to their corresponding 1,3-dioxanes and 1,3-dioxolane with 1,3-propanediol and ethylene glycol, respectively, in the presence of catalytic amount of ZrO(OTf) 2 in acetonitrile at room temperature. The catalyst can be reused several times without loss of its catalytic activity. Very short reaction times, selective acetalization of aromatic aldehydes in the presence of aliphatic aldehydes and ketones, very mild reaction conditions, reusability of the catalyst, and easy workup are noteworthy advantages of this method.
- Moghadam, Majid,Mohammadpoor-Baltork, Iraj,Tangestaninejad, Shahram,Mirkhani, Valiollah,Yazdani, Parvin,Ghorjipoor, Saeedeh
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experimental part
p. 131 - 135
(2009/09/30)
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- A convenient and highly efficient method for the protection of aldehydes using very low loading hydrous ruthenium(III) trichloride as catalyst
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A convenient method for the chemoselective protections of both aliphatic and aromatic aldehydes has been developed. Ruthenium(III) trichloride (0.1 mol %) has found to be an highly efficient catalyst in the acetalizations of aldehydes with various simple alcohols such as methanol, ethanol, or diols such as 1,2-ethylanediol and 1,3-propanediol under mild reaction conditions.
- Qi, Jian-Ying,Ji, Jian-Xin,Yueng, Chi-Hung,Kwong, Hoi-Lun,Chan, Albert S.C.
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p. 7719 - 7721
(2007/10/03)
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- Polyaniline-Supported Sulfuric Acid Salt as a Powerful Catalyst for the Protection and Deprotection of Carbonyl Compounds
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Structurally different carbonyl compounds were converted into their corresponding cyclic acetals using polyaniline-sulfate salt as catalyst in dry toluene in excellent yield. In turn, useful deacetalization in aqueous medium was demonstrated. Chemoselective protection of carbonyl compounds was also demonstrated. The advantages of the polyaniline-sulfate salt are ease of preparation and handling, stability, reusability and activity.
- Palaniappan, Srinivasan,Narender, Puli,Saravanan, Chandrasekaran,Rao, Vaidya Jayathirtha
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p. 1793 - 1796
(2007/10/03)
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- A simple and versatile method for the synthesis of acetals from aldehydes and ketones using bismuth triflate
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Acetals are obtained in good yields by treatment of aldehydes and ketones with trialkyl orthoformate and the corresponding alcohol in the presence of 0.1 mol % Bi(OTf)3·4H2O. A simple procedure for the formation of acetals of diaryl ketones has also been developed. The conversion of carbonyl compounds to the corresponding 1,3-dioxolane using ethylene glycol is also catalyzed by Bi(OTf)3· 4H2O (1 mol %). Two methods, both of which avoid the use of benzene, have been developed.
- Leonard, Nicholas M.,Oswald, Matthew C.,Freiberg, Derek A.,Nattier, Bryce A.,Smith, Russell C.,Mohan, Ram S.
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p. 5202 - 5207
(2007/10/03)
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- Synthesis of monoprotected 1,4-diketones by photoinduced alkylation of enones with 2-substituted-1,3-dioxolanes
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Photosensitized hydrogen abstraction from 2-alkyl-1,3-dioxolanes by triplet benzophenone gives the corresponding 1,3-dioxolan-2-yl radicals and these are trapped by α,β-unsatured ketones yielding monoprotected 1,4-diketones. With open chain ketones (3-buten-2-one and 4-penten-3-one) the yields are low and competitive pathways in part consume the radicals. With cyclic enones however, yields are good as tested with cyclopentenone, cyclohexenone and 4-hydroxy-cyclopentenone. More generally, this is a viable alternative for the synthesis of 1,4-diketones via radicals while the thermal initiation gives only low yield. The reaction cannot be extended to strongly stabilized radicals, such as the 2-phenyl-1,3-dioxolanyl radical.
- Mosca, Raffaella,Fagnoni, Maurizio,Mella, Mariella,Albini, Angelo
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p. 10319 - 10328
(2007/10/03)
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- Silica gel-supported metallic sulfates catalyzed chemoselective acetalization of aldehydes under microwave irradiation
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Silica gel - supported metallic sulfates are found to be efficient catalysts for the protection of both aromatic and aliphatic aldehydes as 1,3- dioxolanes under microwaves in solvent-free conditions. Due to the neutral reaction conditions, this method is compatible with acid sensitive substrates.
- Yadav,Reddy, B. V. Subba,Srinivas,Ramalingam
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p. 701 - 703
(2007/10/03)
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- AN EFFICIENT SbCl3-METAL SYSTEM FOR ALLYLATION, REDUCTION AND ACETALIZATION OF ALDEHYDES
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SbCl3-Fe or SbCl3-Al could induce allylation of aldehydes with allylic halides at room temperature to give high yields of the corresponding homoallylic alcohols with high regio- and chemoselectivity.SbCl3-Al or SbCl3-Zn in DMF-H2O was found to be an efficient reduction system for conversion of aldehydes to alcohols at room temperature in excellent yields.While alcohol was used as solvent instead of DMF-H2O, the acetalization product was obtained in almost quantitative yield.Catalytic amount of SbCl3 was effective for this purpose.This acetalization method could also be applied to ketone.
- Wang, Wei-Bo,Shi, Li-Lan,Huang, Yao-Zeng
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p. 3315 - 3320
(2007/10/02)
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- Efficient Electrocatalytical Acetalization of Aliphatic Aldehydes
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Aliphatic aldehydes are conveniently acetalized by methanol or 1,2-ethanediol at a platinum or carbon anode.The process is electrocatalytic in character.
- Gora, J.,Smigielski, K.,Kula, J.
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p. 586 - 588
(2007/10/02)
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- SYNTHESIS OF DIMETHYL ACETALS, DIETHYL ACETALS, AND CYCLIC ACETALS CATALYZED BY AMINOPROPYLATED SILICA GEL HYDROCHLORIDE (APSG*HCl)
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The aminopropylated Silica-Gel hydrochloride (APSG*HCl) proved to be an efficient catalyst for the rapid conversion of carbonyl compounds in the corresponding acetals with high yields and in mild and selective conditions.In addition to the obvious advantages offered by heterogeneous catalysis, the present method results very useful when the presence of a weakly-acidic function chemically bonded on the catalyst surface (alkyl ammonium salt) is necessary (compounds which contains functions unstable in acidic media).
- Gasparrini, F.,Giovannoli, M.,Misiti, D.,Palmieri, G.
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p. 1491 - 1500
(2007/10/02)
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- RADICAL ADDION OF 1,3-DIOXOLANE TO UNSATURETED COMPOUNDS
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The radical addition of 1,3-dioxolane to 1-hexene and vinyl acetate leads to the formation of 2- and 4-substituted dioxolanes and alkyl formates.The products from the reaction of 1,3-dioxolane with acrylonitrile and dimethyl maleate are 2-alkyl-1,3-dioxolanes.
- Safiev, O. G.,Kruglov, D. E.,Popov, Yu. N.,Zlot-skii, S. S.,Rakhmankulov, D. L.
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p. 997 - 1000
(2007/10/02)
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- Acetals and Ethers. 11. Solubility of Alkyl-Substituted 1,3-Dioxolanes and 1,3-Dioxanes in Water
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2-Alkyl-1,3-dioxolanes, 2-alkyl-4-methyl-1,3-dioxolanes, and 2-alkyl-1,3-dioxanes (alkyl: n-C3H7, ...,n-C6H13) were synthesized and their solubilities in E10-4 M aqueous sodium bicarbonate solution at 293.2 K determined.The standard free energies for transfer from aqueous solution to pure liquid phase, ΔGto, were calculated from the solubility data and the contributions of given fragments of molecules to the free energy estimated.The fve-membered 1,3-dioxolane and six-membered 1,3-dioxane rings given fragments of molecules to the free energy contribution ΔGto, related to the cyclic fragments of the molecules, are +2.84 +/- 0.20 and +2.26 +/- 0.36 kJ mol-1, respectively.Their hydrophilicity is, however, much weaker than hat of the hydroxy group in normal alcohols.The 1,3-dioxolane ring bearing a methyl group at the C-4 atom has a markedly weaker hydrophilic character.
- Sokolowski, Adam,Burczyk, Bogdan,Oles, Jan
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p. 807 - 809
(2007/10/02)
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- ELECTROGENERATED ACID AS AN EFFICIENT CATALYST FOR ACETYLIZATION OF CARBONYL GROUP WITH 1,2-BISTRIMETHYLSILOXYETHANE
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Electrolysis of a mixture of carbonyl compounds and bistrimethylsiloxyethane in CH2Cl2-LiClO4-(Pt) readily gave the corresponding acetalized products in good yields.
- Torii, Sigeru,Inokuchi, Tsutomu
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p. 1349 - 1350
(2007/10/02)
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