- Synthesis and application of a spirocompound as clean viscosity-reducer for crude oil
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Heavy oil transportation has become a highly technical operation facing complex difficulties. One of the major difficulties in the pipeline transportation is the high viscosity that requires efficient and economical ways to deal with. The typical polymer viscosity reducers are a negative problem during oil refinement process for their chemical properties. The objective of this study is to seek small molecular compound, different from the traditional polymers, to reduce the viscosity of the crude oil. In this work, a spirocompound, 3,9-diphenyl-2,4,8,10-tetraoxa-spiro[ 5.5 ]undecane, was synthesized catalyzed by zeolite and modified zeolite, and the product was fully characterized by NMR, MS, and TG. Then, it was used as viscosity reducer for crude oil. The factors such as dosage and temperature on the viscosity behavior have been studied. The results showed a significant viscosity reduction at different temperature, and the most economical dosage is 500 ppm. The multiphenyl groups can interact with asphaltene by π - π stacking, and the spirostructure can fix the stacking in different direction, which can prevent the agglomeration of wax crystals.
- Chen, Shijun,Zhao, Kang,Chen, Gang,Bai, Li,Feng, Lajun
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Read Online
- Novel synthesis method of ester free trimethylene carbonate derivatives
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Ester free poly(trimethylene carbonate) (PTMC) derivatives show biocompatibility and biodegradability and do not generate any acidic compounds after decomposition. Their syntheses methods are limited however, hampering their material application. Herein, we established a novel synthesis route of ester free trimethylene carbonate (TMC) derivatives. The novel synthesis route was described using six aldehydes and one ketone as starting compounds. The key reaction is the selective deprotection from two protected hydroxyl groups in the cyclic acetal structure by diisobutylaluminium hydride. This novel synthesis route means that it is possible to convert aldehyde group to ether groups in the side chain of TMC. Conventionally, only a substituent derived from a primary alcohol was introduced into the side chain. We therefore succeeded in decreasing the number of reaction steps from five to three, compared with the conventional route. Furthermore, the development of a novel synthesis route enabled the introduction of substituents derived from secondary alcohols, anticipating the creation of further types of ester free TMC derivatives.
- Nobuoka, Hiroaki,Ajiro, Hiroharu
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p. 164 - 170
(2019/01/04)
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- Hierarchical MFI Zeolites with a Single-Crystalline Sponge-Like Mesostructure
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Single-crystalline sponge-like MFI mesoporous zeolites (SSMZs) have been synthesized by using bolaform surfactants with an axial chiral binaphthyl core in the hydrophobic tail and triquaternary ammonium head groups, as bifunctional organic structure-directing agents (OSDAs). By changing the length of alkyl chain between a triquaternary ammonium head group and a binaphthyl group from 4 to 10 carbons, SSMZs with high specific surface area (382–434 m2 g?1), abundant micropore-mesopore connectivity, and uniform mesopore diameter (4–10 nm) were obtained. OSDAs with an alkyl chain length of 11 and 12 carbons led to the formation of nanorod-constructed mesoporous MFI zeolites. A geometrical matching between the cylindrical arrangement of the binaphthyl groups and the zeolitic framework is speculated to be the key factor for the formation of mesoporous zeolites. The SSMZ zeolites, with abundant mesopores beneficial for the diffusion of reactants, exhibited significantly higher catalytic efficiencies than those of the conventional ZSM-5 with a microcrystal morphology (≈1.5 μm).
- Zhang, Yunjuan,Luo, Peng,Xu, Hao,Han, Lu,Wu, Peng,Sun, Huai,Che, Shunai
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supporting information
p. 19300 - 19308
(2018/11/27)
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- From organocatalysed desilylations to high-yielding benzylidenations of electron-deficient benzaldehydes
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A new type of organoprecatalyst (MeSCH2Cl/KI) for desilylation and benzylidenation reactions has been designed. Both reactions are user friendly and high yielding (71->99%) and have fast reaction rates. The desilylation of iodo silyl ethers was achieved with no sequential etherification side reactions like those seen for reactions when using TBAF. In the application of the catalytic system to a 6-TBDMS ether of a glucoside, glucoside benzylidenations using electron-deficient benzaldehydes were achieved in 87% yield compared with the previously reported yields of 69-77%. Altogether, 14 benzylidenation reactions were realised using silyloxy alcohols and electrondeficient benzaldehydes instead of their activated acetal forms. In terms of reaction rates and yields, the order of the benzylidenations is p-fluorobenzaldehyde > benzaldehyde > p-anisaldehyde, and a possible mechanism is discussed. These experiments have preliminarily differentiated this cost-effective catalytic system from the classic Lewis acids.
- Niu, Qun,Xing, Linlin,Li, Chunbao
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p. 358 - 364
(2017/06/19)
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- Acetalization of carbonyl compounds as pentaerythritol diacetals and diketals in the presence of cellulose sulfuric acid as an efficient, biodegradable and reusable catalyst
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This paper reports a practical and green method for the acetalization of carbonyl compounds as pentaerythritol diacetals and diketals derivatives using cellulose sulfuric acid as a biodegradable and reusable solid acid catalyst under thermal solvent-free conditions.
- Shaterian, Hamid Reza,Rigi, Fatemeh
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experimental part
p. 695 - 698
(2012/05/05)
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- A green recyclable poly(4-vinylpyridine)-supported copper iodide nanoparticle catalyst for the chemoselective synthesis of pentaerythritol diacetals from aromatic aldehydes
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Poly(4-vinylpyridine)-supported copper(I) iodide nanoparticles have been used as an efficient, green recyclable catalyst for the chemoselective synthesis of pentaerythritol diacetals from aromatic aldehydes and pentaerythritol under solvent-free conditions. This catalyst was reused six times without any loss of its activity.
- Albadi, Jalal,Iravani, Nasir,Dehghan, Farzaneh,Shirinic, Farhad
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p. 610 - 611,2
(2020/09/16)
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- ZSM-5 zeolite single crystals with b-axis-aligned mesoporous channels as an efficient catalyst for conversion of bulky organic molecules
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The relatively small and sole micropores in zeolite catalysts strongly influence the mass transfer and catalytic conversion of bulky molecules. We report here aluminosilicate zeolite ZSM-5 single crystals with b-axis-aligned mesopores, synthesized using a designed cationicamphiphilic copolymer as a mesoscale template. This sample exhibits excellent hydrothermal stability. The orientation of the mesopores was confirmed by scanning and transmission electron microscopy. More importantly, the b-axis-aligned mesoporous ZSM-5 shows much higher catalytic activities for bulky substrate conversion than conventional ZSM-5 and ZSM-5 with randomly oriented mesopores. The combination of good hydrothermal stability with high activities is important for design of novel zeolite catalysts. The b-axis-aligned mesoporous ZSM-5 reported here shows great potential for industrial applications.
- Liu, Fujian,Willhammar, Tom,Wang, Liang,Zhu, Longfeng,Sun, Qi,Meng, Xiangju,Carrillo-Cabrera, Wilder,Zou, Xiaodong,Xiao, Feng-Shou
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supporting information; experimental part
p. 4557 - 4560
(2012/04/23)
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- Acetalation of pentaerithritol catalyzed by an Al-pillared saponite
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Acetalation of pentaerithritol has been carried out in the presence of an Al-pillared saponite. Several carbonyl compounds were used, including aldehydes and ketones. Yields between 72 and 93% were obtained in all cases, except in the case of veratraldehyde where the carbonyl group was blocked. The high conversion could be explained by diffusion effects of intermediates and electronic effects between the reactants in the transition state. The catalyst was found to be active after three cycles.
- Kannan,Sreekumar,Gil,Vicente
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experimental part
p. 1118 - 1122
(2012/06/18)
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- SO3H-functionalized ionic liquids as efficient and recyclable catalysts for the synthesis of pentaerythritol diacetals and diketals
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The efficient, simple and environmentally friendly synthesis of pentaerythritol diacetals and diketals using SO3H-functionalized ionic liquids (ILs) as catalysts was reported. The ILs showed high catalytic activities and reusabilities with good to excellent yields of the desired products. H0 (Hammett function) values and the minimum-energy geometries of SO3H-functionalized ILs were determined and the results revealed that the acidities and catalytic activities of ILs in acetalization were related to their structures. The IL [PSPy][OTf] with the shortest H-O bond distance had the strongest acidity and the highest catalytic activity in the synthesis of pentaerythritol diacetals and diketals.
- Wang, Yuanyuan,Gong, Xinxin,Wang, Zhizhong,Dai, Liyi
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experimental part
p. 7 - 16
(2010/07/09)
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- A new approach to the synthesis of diacetals (diketals) pentaerythritol catalyzed by SO3H-functionalized ionic liquids
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In this article, an efficient, simple and environmentally friendly approach to the synthesis of diacetals (diketals) pentaerythritol using SO3H-functionalized ionic liquids (ILs) as catalysts was reported. The ILs show high catalytic activity and reusability with good to excellent yields of the desired products. Hammett method has been used to determine the acidity order of these ionic liquids and the results are consistent with the catalytic activities observed in acetalization reaction. Maximum product yield of 93% was observed on using [PSPy][OTf] as catalyst and it can be reused at least 8 times without obvious activity loss.
- Wang, Yuan Yuan,Xu, Yan Nan,Wang, Zhi Zhong,Dai, Li Yi
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experimental part
p. 524 - 528
(2011/02/21)
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- N-bromosuccinimide (NBS) catalyzed highly chemoselective acetalization of carbonyl compounds using silylated diols and pentaerythritol under neutral aprotic conditions
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Various types of carbonyl compounds are efficiently converted to their 1,3-dioxanes and pentaerythritol diacetals by the use of either 1,3-bistrimethylsiloxy propane (A) or 1,3-bistrimethylsilanyloxy-2,2- bistrimethylsilanyloxymethyl propane (D) and a catalytic amount of N-bromosuccinimide (3-10 mol%) under essentially neutral aprotic condition, respectively. A variety of functionalities such as both aliphatic and phenolic -OTBDMS, -OMe, -OBz, furan ring, double bonds and more significantly phenolic -OTHP survived under the present reaction condition. The efficient conversion of two α-tertiary ketones to their cyclic acetals was also achieved using the present protocol.
- Karimi, Babak,Hazarkhani, Hassan,Maleki, Jafar
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p. 279 - 285
(2007/10/03)
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- Stripping off water at ambient temperature: Direct atom-efficient acetal formation between aldehydes and diols catalyzed by water-tolerant and recoverable vanadyl triflate
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(Chemical Equation Presented) Aromatic aldehydes can be readily protected as acetals with 1,2- and 1,3-diols by using vanadyl triflate as a catalyst in CH3CN at ambient temperature. Carbohydrate-based 1,2- and 1,3-diols can similarly be protected in good to excellent yields. The catalyst can be readily recovered from the aqueous layer. In combination with vanadyl triflate-catalyzed sequential regioselective, reductive acetal opening and chemoselective acylations, the title method allows for differential functionalization of all four hydroxyl units in a given glucopyranoside.
- Chen, Chien-Tien,Weng, Shiue-Shien,Kao, Jun-Qi,Lin, Chun-Cheng,Jan, Mi-Dan
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p. 3343 - 3346
(2007/10/03)
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- Synthesis of diacetals from aldehydes and ketones with pentaerythritol catalysed by the ZrO2/S2O82- solid superacid
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A manipulatively simple and rapid procedure for the synthesis of diacetals from 2,2-bis(hydroxymethyl)-1, 3-propanediol with aldehydes and ketones in refluxing benzene or toluene using the ZRO2/S2O 82- solid superacid as catalyst in 80-98% yields has been described.
- Jin, Tongshou,Yang, Mina,Wang, Xin,Feng, Guoliang,Li, Tongshuang
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p. 203 - 205
(2007/10/03)
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- Synthesis of diacetals from aldehydes and ketones with pentaerythritol catalyzed by silica sulfate under microwave irradiation
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The synthesis of diacetals from pentaerythritol with aldehydes and ketones is carried out under microwave irradiation in 80-98% yields with silica sulfate as catalyst.
- Jin, Tong-Shou,Wang, Huan-Xin,Wang, Kai-Fang,Li, Tong-Shuang
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p. 2993 - 2999
(2007/10/03)
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- Synthesis of functionalised derivatives of pentaerythritol
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Ring opening of the dibenzylidene derivative of pentaerythritol 12 with N-bromosuccinimide gave di-O-benzoyldibromodideoxypentaerythritol (29). Reaction of 20 and 21 with hydrogen bromide in acetic acid afforded di-O-acetyl-di-O-p-toluenesulfonyl pentaerythritol (26). Nucleophilic displacement of the tosyloxy groups in 20 by 1,2,4 triazole afforded 2-phenyl-5-(p-toluenesulfonyloxymethyl)-5-(1,2,4-triazolylmethyl)-1,3-dioxan (31) and 2-phenyl-5,5-bis(1,2,4-triazolylmethyl)-1,3-dioxan (32), and with benzotriazole gave 2-phenyl-5,5-bis(benzotriazolylmethyl)-1,3-dioxan (30). The activity of various derivatives against hepatitis B virus has been studied.
- Ashry, E. S. H. El,Kilany, Y. El,Hamid, H. Abdel,El-Zemity, S. R.,Boghdady, S.
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p. 111 - 128
(2007/10/03)
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- An efficient procedure for the synthesis of diacetals from the InCl3·4H2O catalysed reaction of 2,2-bis (hydroxymethyl)-1,3-propanediol with aldehydes or ketones
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Diacetals of carbonyl compounds are synthesised in good yields by the InCl3·4H2O catalysed condensation reactions.
- Deng, Guisheng,Ren, Tiegan
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- New applications of solid silica chloride (SiO2-Cl) in organic synthesis. Efficient preparation of diacetals of 2,2-bis(hydroxymethyl)-1,3-propanediol from different substrates and their transthioacetalization reactions. Efficient regeneration of carbonyl compounds from acetals and acylals
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A new application of solid silica chloride, an easily available and efficient catalyst for the preparation of diacetal of 2,2-bis-(hydroxymethyl)-1,3-propanediol from aldehydes, acetals, acylals, and oximes, is described. Transthioacetalization of diacetals of 2,2-bis-(hydroxymethyl)-1,3-propanediol into their corresponding 1,3-dithianes and 1,3-dithiolanes in the presence of silica chloride is presented. Efficient regeneration of carbonyl compounds from their corresponding acetals, ketals, diacetals, and acylals in the presence of this catalyst also is described.
- Firouzabadi, Habib,Iranpoor, Nasser,Hazarkhani, Hassan
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p. 2847 - 2858
(2007/10/03)
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- Synthesis and structure of 2-aryl-5,5-disubstituted-1,3-dioxanes and conversion into chiral (1,1,1-trishydroxymethyl) methane derivatives
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Pentaerythritol, (1,1,1-trishydroxymethyl)methyl methane and (1,1,1-trishydroxymethyl)nitromethane are converted into 2-aryl-5,5-bis(hydroxymethyl), 2-aryl-5-hydroxymethyl-5-methyl- or 2-aryl-5-hydroxymethyl-5-nitro-1,3-dioxanes and a range of derivatives. X-Ray and NMR analysis establishes that the latter is obtained as a single diastereomer whose structure is unambiguously determined. These materials can be elaborated to chiral derivatives of the starting (1,1,1-trishydroxymethyl) methanes.
- Gardiner, John M,Mather, Paul,Morjan, Ramy,Pritchard, Robin G,Warren, John E,Cooper, Malcolm L,Ferwanah, Abd El-Rahman S,Abu-Tiem, Omar S
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p. 2091 - 2094
(2007/10/03)
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- 2,4,4,6-Tetrabromo-2,5-cyclohexadienone (TABCO) as a versatile, efficient, and chemoselective catalyst for the acetalization and transacetalization of carbonyl compounds, the preparation of acetonides from epoxides and acylals (1,1-diacetates) from aldehydes
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The efficient and chemoselective preparation of acetals and ketals from carbonyl compounds, transacetalization reactions, the conversion of epoxides to acetonides, and the preparation of acylals from aldehydes in the presence of catalytic amounts of 2,4,4,6-tetrabromo-2,5-cyclohexadienone (TABCO) are described.
- Firouzabadi, Habib,Iranpoor, Nasser,Shaterian, Hamid Reza
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p. 2195 - 2205
(2007/10/03)
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- Microwave-assisted acetalization of pentaerythritol catalyzed by 12-tungstophosphoric acid
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Efficient conversion of carbonyl compounds and pentaerythritol to corresponding diacetals in the presence of 12-tungstophosphoric acid under microwave irradiation is described.
- Peng,Song,Qian
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p. 3735 - 3738
(2007/10/03)
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- A practical and efficient procedure for preparation of diacetals from 2,2-bis (hydroxymethyl) propane-1,3-diol with aldehydes and ketones catalysed by anhydrous ferrous sulfate
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Synthesis of diacetals in excellent yields from aldehydes and ketones with 2,2-bis(hydroxymethyl)propane-1,3-diol is carried out in refluxing benzene or toluene with anhydrous ferrous sulfate as catalyst.
- Jin, Tong-Shou,Ma, Yan-Ran,Li, Tong-Shuang,Wang, Jian-Xin
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p. 268 - 269
(2007/10/03)
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- Synthesis of diacetals by condensation of carbonyl compounds with bis(hydroxymethyl)-1,3-propanediol catalysed by expansive graphite
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Synthesis of diacetals from 2,2-bis(hydroxymethyl)-1,3-propanediol with aldehydes and ketones under catalysis of expansive graphite in refluxing benzene or toluene in good to excellent yield has been described.
- Jin, Tong-Shou,Li, Tong-Shuang,Zhang, Zhan-Hui,Yuan, Yan-Jun
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p. 1601 - 1606
(2007/10/03)
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- Montmorillonite Clays Catalysis. Part 12.1 An Efficient and Practical Procedure for Synthesis of Diacetals from 2,2-Bis(hydroxymethyl)propane-1,3-diol with Carbonyl Compounds
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Preparation of diacetals from 2,2-bis(hydroxymethyl)propane-1,3-diol with aldehydes and ketones is catalysed by montmorillonite clays in refluxing benzene or toluene in good to excellent yield.
- Zhang, Zhan-Hui,Li, Tong-Shuang,Jin, Tong-Shou,Li, Ji-Tai
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p. 640 - 641
(2007/10/03)
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- Synthesis of diacetals of 2,2-bis(hydroxymethyl)1,3-propanediol under microwave irradiation
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Nine diacetals (3a-i) of 2,2-bis(hydroxymethyl)-1,3-propanediol (2) were prepared by condensation of aldehydes with 2 under microwave irradiation in the presence of TsOH without solvent.
- Wang, Cun-De,Shi, Xin-Zhong,Xie, Ren-Jian
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p. 2517 - 2520
(2007/10/03)
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