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PdCl_2-Mn(OAc)_2催化苯酚氧化羰基化合成碳酸二苯酯 总被引:2,自引:0,他引:2
碳酸二苯酯 ( DPC)是重要的有机碳酸酯 ,它可用于合成许多有机化合物、医药、农药、高分子材料等 [1] .最近日本 Ashia公司与意大利Enichem公司联合开发了双酚 A与 DPC经熔融聚合法制备聚碳酸酯的非光气法新工艺 [2 ] ,使得聚碳酸酯生产工艺朝“绿色化清洁生产”方向取得突破性进展 ,也使得 DPC的合成成为研究的热点 .合成 DPC的方法有光气法、酯交换法及氧化羰基化法 ,其中 ,氧化羰基化法更是引人注目 [1,3 ] ,它是用苯酚与 CO、O2 反应一步合成 DPC的方法 ,具有工艺简单 ,原料易得等优点 ,且避免了使用剧毒的光气 ,是一条“绿色… 相似文献
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氨基甲酸酯是合成农药、医药及异氰酸酯的重要中间体^[1,2].传统的氨基甲酸酯的制备是以光气及其衍生物和胺为原料^[3],该工艺使用剧毒的光气,同时副产腐蚀性的HCl.因此,对环境友好的非光气法合成氨基甲酸酯成为当今发展的主流^[4,5].由胺与碳酸二甲酯反应合成氨基甲酸酯是近年发展起来的非光气法,用碳酸二甲酯代替光气合成氨基甲酸酯可以实现环保要求,反应过程中的唯一副产物甲醇可以循环利用.该反应通常在硝酸铅^[6]、γ—Al2O3^[7]、Zn(OAc)2和三氟化镱^[8,9]等催化条件下进行.但上述催化剂存在催化活性低, 相似文献
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二苯甲酮是一种重要的精细化工中间体和添加剂[1,2],主要应用于光敏剂、化学合成药物、香料香精、涂料、日用化工及电子化学品等领域。目前,二苯甲酮在工业上有多种合成工艺路线[3-6],其中包括光气法、苯甲酰氯法、三氯甲苯法、苯甲酸法、格式试剂法等。然而这些方法在不同程度 相似文献
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Hans-Dieter Scharf 《Angewandte Chemie (International ed. in English)》1974,13(8):520-533
Monohalo- and dihalovinylene carbonates constitute a new class of cyclophiles which permit simultaneous introduction of masked α-hydroxyketo and α-diketo functions, respectively, into the cycloadducts. Demasking can be performed by simple hydrolysis. Solvolytic opening of the carbonate ring leads to glycolic acid derivatives in the case of the monohalo compounds and to glyoxylic acid derivatives with the dihalo compounds. Preparation of the title compounds, their potential as synthetic reagents, and the chemistry of their simple reaction products are surveyed from a preparative viewpoint. 相似文献
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环状碳酸酯低聚物的合成及其开环聚合的研究 总被引:4,自引:0,他引:4
环状碳酸酯低聚物的合成及其开环聚合的研究陈雨萍魏玮李革(中国科学院化学研究所工程塑料国家重点实验室北京100080)关键词环状碳酸酯低聚物,聚碳酸酯,开环聚合环状单体的开环聚合在合成高聚物方面具有突出的优点,即在聚合过程中没有副产物、热效应低、聚合... 相似文献
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An efficient and convenient synthesis of ethylene carbonates was achieved by the reaction of carbon dioxide with 1,2-diols in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), followed by treatment with 1-bromobutane. This DBU-promoted transformation proceeded at an atmospheric pressure of carbon dioxide at 25 °C and gave ethylene carbonates in good yields. 相似文献
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Various allylic aryl sulphides are readily prepared in high yields by the palladium(0)-catalyzed S-alkylation of allylic carbonates by various aromatic thiols. 相似文献
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Silver(I)‐Catalyzed Three‐Component Reaction of Propargylic Alcohols,Carbon Dioxide and Monohydric Alcohols: Thermodynamically Feasible Access to β‐Oxopropyl Carbonates 下载免费PDF全文
Zhi‐Hua Zhou Dr. Qing‐Wen Song Jia‐Ning Xie Ran Ma Prof. Dr. Liang‐Nian He 《化学:亚洲杂志》2016,11(14):2065-2071
A silver(I)‐catalyzed three‐component reaction of propargylic alcohols, CO2, and monohydric alcohols was successfully developed for the synthesis of β‐oxopropyl carbonates. As such, a series of β‐oxopropyl carbonates were exclusively produced in excellent yields (up to 98 %), even under atmospheric pressure of CO2. The silver catalyst works efficiently for both the carboxylative cyclization of propargylic alcohols with CO2 and subsequent transesterification of α‐alkylidene cyclic carbonates with monohydric alcohols; thus this tandem process performs smoothly under mild conditions. This work provides a versatile and thermodynamically favorable approach to dissymmetric dialkyl carbonates. 相似文献
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M. L. Franquelo M. D. Robador V. Ramírez-Valle A. Durán M. C. Jiménez de Haro J. L. Pérez-Rodríguez 《Journal of Thermal Analysis and Calorimetry》2008,92(1):331-335
Roman ceramics of two hydraulic mortars used to build the pond and water channel of Mithraeum house from Mérida (Spain) have
been studied. The sizes of the ceramic fragments found were different in both of the samples studied, showing different behaviour
in the reactions with the lime. The X-ray diffraction of the ceramic shows the presence of quartz, mica (biotite), anorthite
and hematite accompanied by amorphous phase, being observed scarce vitrification. The presence of mica confirms a firing temperature
for manufacturing the ceramic below 900°C. In one of the ceramics studied, X-ray diffraction did not show calcite. However,
in the FTIR appear bands that could be assigned to carbonates absorptions and likewise, carbonates were identified in the
DTA-TG curves. Ca and small quantities of Si and Al were also identified by SEM-EDX on the surface of the pores that could
be due to an amorphous phase formed in the reaction of lime with the Si and Al of the ceramic. On the other hand, in other
ceramic samples carbonates (about 10%) were detected. The carbonates have been found filling the pores, sometimes accompanied
by a new calcium-aluminium-silicate phase produced by the reaction between the lime and the amorphous phase of the ceramic.
The carbonates and the new phases formed inside the pores are responsible for the decrease of the porosity and for the formation
of new phases during the heating of the ceramics. 相似文献
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Dr. Cristian Vicent Dr. Kathrin Junge Prof. Dr. Matthias Beller 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(47):16759-16763
Methylation of amines is a fundamental and commonly used reaction in organic synthesis. Many methods are known including various reductive methylations using formaldehyde, formic acid, or carbon dioxide in the presence of reductants. However, several of these methods suffer from limited substrate scope and chemoselectivity because of the different nucleophilicities of substrates. In this respect, the combination of carbonates and hydrosilanes is a valuable methylation source in the presence of Pt‐based catalysts. This highly tunable method allows for methylation of both aromatic and aliphatic amines, and chemoselective methylation of aminoalcohols and diamines. Notably, the in situ‐formed catalyst can also be used for the reduction of carbonates to methanol at room temperature. Mechanistic insights on intermediates formed during the reaction pathway were obtained by using ESI mass spectrometry. 相似文献
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Zhong-Xiang Jiang 《Journal of fluorine chemistry》2003,123(1):57-60
Trifluoromethylated cyclic carbonates were prepared through the palladium-promoted reaction of tertiary trifluoromethylated propargylic alcohols and sodium carbonate. 相似文献
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Stereospecific Pd‐Catalyzed Intermolecular C(sp3)–C(sp) Cross‐Coupling of Diarylmethyl Carbonates and Terminal Alkynes Under Base‐Free Conditions 下载免费PDF全文
Sho Tabuchi Prof. Dr. Koji Hirano Prof. Dr. Masahiro Miura 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(47):16823-16827
A palladium‐catalyzed intermolecular decarboxylative C(sp3)–C(sp) coupling of diarylmethyl carbonates and terminal alkynes has been developed. The reaction proceeds smoothly under external base‐free conditions to deliver the corresponding alkynylated diarylmethanes with the liberation of CO2 and MeOH as the sole byproducts. Moreover, enantioenriched diarylmethyl carbonates are stereospecifically converted to optically active cross‐coupling products with inversion of configuration. Thus, the stereospecific palladium catalysis can provide new and unique access to the alkynylated chiral tertiary stereocenters, which are relatively difficult to construct by conventional methods. 相似文献