N510与D2EHDTPA对钯的协同萃取

用 2 -羟基 -5 -仲辛基 -二苯甲酮肟 (N5 1 0 )与二 -(2 -乙基己基 )二硫代磷酸 (D2 EHDTPA)的氯仿溶液 ,从高氯酸介质中对钯的协同萃取进行了研究。采用斜率法确定了萃合物的组成为 :L· Pd· A,协萃反应平衡常数为 lg K1 2 =1 .67,协同萃取配合物生成常数为 β1 2 =3 .3 0。同时计算了协同萃取反应的热力学函数值。     

工程轮胎修补胶国产化研制

根据矿山井下工程轮眙的使用要求,结合引进TIP.TOP公司修补胶的物性炼点,经过反复试验研制出的自制修补胶片物性接近与进口胶片,且成本低廉,完全满足了工程轮胎修补需要。     

地方病高发区成井用胶质水泥浆的试验研究

通过地方病高发区成井用胶质水泥浆的试验研究，以普通水泥和膨润土为基本材料，同时添加改善材料性能的外加剂，研制了一种用于高砷、高氟、高矿化度地区水井成井的止水材料，具有流动性好、抗渗性高、不收缩、完全无毒、价格低廉等特点，特别是其高抗渗性和不收缩性非常适合地方病区成井时隔离劣质含水层，保证优质含水层与劣质含水层互不串通、不渗漏、不污染。     

Catalysis of semihydrogenation of acetylene to ethylene: current trends,challenges, and outlook

Ethylene is an important feedstock for various industrial processes, particularly in the polymer industry. Unfortunately, during naphtha cracking to produce ethylene, there are instances of acetylene presence in the product stream, which poisons the Ziegler–Natta polymerization catalysts. Thus, appropriate process modification, optimization, and in particular, catalyst design are essential to ensure the production of highly pure ethylene that is suitable as a feedstock in polymerization reactions. Accordingly, carefully selected process parameters and the application of various catalyst systems have been optimized for this purpose. This review provides a holistic view of the recent reports on the selective hydrogenation of acetylene. Previously published reviews were limited to Pd catalysts. However, effective new metal and non-metal catalysts have been explored for selective acetylene hydrogenation. Updates on this recent progress and more comprehensive computational studies that are now available for the reaction are described herein. In addition to the favored Pd catalysts, other catalyst systems including mono, bimetallic, trimetallic, and ionic catalysts are presented. The specific role(s) that each process parameter plays to achieve high acetylene conversion and ethylene selectivity is discussed. Attempts have been made to elucidate the possible catalyst deactivation mechanisms involved in the reaction. Extensive reports suggest that acetylene adsorption occurs through an active single-site mechanism rather than via dual active sites. An increase in the reaction temperature affords high acetylene conversion and ethylene selectivity to obtain reactant streams free of ethylene. Conflicting findings to this trend have reported the presence of ethylene in the feed stream. This review will serve as a useful resource of condensed information for researchers in the field of acetylene-selective hydrogenation.     

Mathematical modeling of the partial hydrogenation of vegetable oil in a monolithic stirrer reactor

Experimental and theoretical studies on the partial hydrogenation of vegetable oil in a monolithic stirrer reactor are reported. A complete mathematical model of the reactor was developed, including hydrogenation and isomerization kinetics, catalyst deactivation, external gas–liquid and liquid–solid as well as internal mass transfer. The experimental studies were carried out in a Pd/Al₂O₃/Al monolithic stirrer reactor, at a wide range of temperatures (353–373 K), pressures (414–552 kPa), and catalyst loadings (0.00084–0.00527 kg_Pd,exp m^?3). Based on this model, simulated data can be used to evaluate the catalyst (Pd/Al₂O₃/Al) and the hydrogenation process in consecutive catalytic tests under different operating conditions. © 2014 American Institute of Chemical Engineers AIChE J, 60: 3524–3533, 2014     

钯催化Suzuki偶联反应的研究进展

金属Pd催化的Suzuki偶联反应是碳-碳偶联反应中重要的反应之一。综述了近年来Pd催化Suzuki偶联反应的研究进展,其中包括Suzuki反应机理、配体种类及其在有机合成中的应用。介绍了含N、P配体的钯催化剂和碳纳米管、磁性材料、多孔材料、水滑石、金属氧化物、高分子材料等负载的无配体钯催化剂的研究进展。     

Phosphaannulation of Aryl‐ and Benzylphosphonic Acids with Unactivated Alkenes via Palladium‐Catalyzed C?H Activation/Oxidative Cyclization Reaction

An efficient phosphaannulation via palladium(II)‐catalyzed C H activation/oxidative cyclization by the 6‐endo mode is reported for the synthesis of 3‐substituted phosphaisocoumarins from the reaction of arylphosphonic acids with unactivated alkenes under aerobic conditions. Also, α,α‐disubstituted benzylphosphonic acids were phosphaannulated with unactivated alkenes, producing phosphaisochromanones having (Z)‐alkylidenyl groups via anti‐phosphoryloxypalladation by the 6‐exo mode.

     

Palladium‐Catalyzed Construction of Spirooxindoles by Arylative Cyclization of 3‐(γ,δ‐Disubstituted)allylidene‐2‐Oxindoles

The palladium‐catalyzed, one‐pot arylative cyclization of 3‐(γ,δ‐disubstituted)allylidene‐2‐oxindoles afforded spirodihydronaphthalene‐2‐oxindole frameworks via an oxidative Heck arylation (Fujiwara–Moritani reaction), an allylic palladium migration, and an aryl C H bond functionalization/arylation cascade of reactions. This is a first example of the palladium‐catalyzed oxidative arylation and an aryl C H bond functionalization/arylation cascade reaction which involves an electrophilic arylative quenching of a π‐allylpalladium intermediate and a regio‐controlled aryl C H bond activation assisted by a weak palladium‐arene interaction.

     

From Isonitriles to Unsaturated NHC Complexes of Gold,Palladium and Platinum

In a modular template synthesis, unsaturated NHC complexes of gold, palladium and platinum were synthesized from simple metal salts, isonitriles and amines with acetal or ketal groups. Upon the addition of amines with tethered acetal or ketal moieties to the metal‐activated isonitrile, first nitrogen acyclic carbene (NAC) complexes are formed. These undergo ring closure and elimination to the unsaturated NHC complexes upon addition of acid. This simple strategy opens an attractive and fast approach to NHC complexes of gold, palladium and platinum. The modular approach allows a fast modification and is well‐suited for the synthesis of unsymetrically and symmetrically substituted unsaturated NHC complexes.

     

Easy,Green and Safe Carbonylation Reactions through Zeolite‐Catalyzed Carbon Monoxide Production from Formic Acid

Zeolites with the right shape and acid site density and strength, such as certain ZSM‐5 forms, were able to cleanly decompose formic acid to carbon monoxide (CO), and the latter could be directly used in palladium‐catalyzed carbonylation reactions. A simple two‐reactor system was designed to produce CO conveniently and then further react this gas in a safe way. The two‐reactor system is particularly cheap, easy to set up and use. In addition, the carbonylation conditions without pressure allowed for very efficient CO incorporation, with only 1% of palladium(II) chloride (PdCl₂) and Xantphos.