生物柴油及1,3-丙二醇联产工艺产业化进展

生物柴油作为可再生的清洁能源,已在美国、欧盟等多个国家和地区推行使用.在生物柴油的生产过程中,最高可得到约10%的副产物甘油,副产物甘油的去向将成为生物柴油大规模产业化发展所面临的严峻问题.1,3-丙二醇是一种重要的化工原料,作为合成新型聚酯PTT的原料,1,3-丙二醇已引起人们的广泛关注.以生物柴油副产物甘油为原料耦合生产1,3-丙二醇,不仅解决了生物柴油副产物甘油的出路问题,同时降低了1,3-丙二醇的生产成本.本文详细介绍了生物柴油及1,3-丙二醇生产技术及联产工艺的研究进展,并对其应用前景进行了展望.     

生物柴油及1,3-丙二醇联产工艺产业化进展

生物柴油作为可再生的清洁能源,已在美国、欧盟等多个国家和地区推行使用。在生物柴油的生产过程中,最高可得到约10%的副产物甘油,副产物甘油的去向将成为生物柴油大规模产业化发展所面临的严峻问题。1,3-丙二醇是一种重要的化工原料,作为合成新型聚酯PTT的原料,1,3-丙二醇已引起人们的广泛关注。以生物柴油副产物甘油为原料耦合生产1,3-丙二醇,不仅解决了生物柴油副产物甘油的出路问题,同时降低了1,3-丙二醇的生产成本。本文详细介绍了生物柴油及1,3-丙二醇生产技术及联产工艺的研究进展,并对其应用前景进行了展望。     

甘油催化氢解制备精细化学品的研究进展

随着生物柴油产业的快速发展,作为副产物的甘油大量过剩,因而有效利用甘油既能促进生物柴油产业的良性发展,又能节约大量石油资源。通过甘油催化氢解的方式来制备高附加值化学品丙二醇、乙二醇和丙醇等是甘油转化研究中最有潜在应用价值的路径之一,甘油氢解反应易于实现连续化生产,且目标产物附加值高、选择性高,因而具有良好的经济效益。本文首先简要介绍了甘油化学,深入探讨了甘油的氢解机理,然后重点综述了甘油氢解制备1, 2-丙二醇、1, 3-丙二醇、乙二醇和丙醇高效催化剂的研究进展,并对甘油氢解未来的研究方向和发展趋势作了进一步展望。     

甘油催化氢解的研究与应用

近年来由于生物柴油产业的快速发展,甘油作为其生产过程中的副产品大量生成,合理利用这些过剩的甘油将有助于增加整个生物柴油产业的经济效益。本文对近年来利用甘油为原料催化氢解合成二元醇（1,2-丙二醇、1,3-丙二醇和乙二醇）的研究进展进行了综述,介绍了甘油催化氢解的研究背景,着重讨论了甘油催化氢解生成二元醇的反应机理（包括脱水-加氢机理、脱氢-加氢机理和螯合机理）和甘油催化氢解在生产二元醇上的应用,并对甘油催化氢解的发展前景做了展望。     

甘油催化氢解制备1,2-丙二醇催化剂研究进展

综述了近年来通过生物柴油生产过程中的副产物甘油催化氢解制备高附加值1,2-丙二醇的催化剂研究新进展.对各类催化剂的研究工作做了简要的总结,并对研究热点做出展望.     

生物基甘油氢解合成1,3-丙二醇催化剂的研究进展

1,3-丙二醇（1,3-PDO）作为聚酯单体原料有广阔的市场空间,在化妆品和医药等领域也被广泛应用.由生物基甘油选择氢解一步法合成1,3-PDO工艺被认为是一条绿色环保和高经济性的技术路线.我们在这里主要介绍了甘油氢解制备1,3-PDO催化剂的研究进展,对催化剂类型、催化剂的合成方法和工艺条件进行了归类总结;分析了多种催化剂体系的甘油氢解反应机理,指出了该反应工业化过程中存在的一些问题,并展望了今后的研究发展方向.     

甘油在微生物代谢合成及生物催化中的应用

生物柴油是一种可再生能源,因其可替代石油来源的柴油而日益受到重视。随着生物柴油工业的蓬勃发展,其制备过程中的主要副产物甘油出现明显的产能过剩。作为一种廉价的清洁资源,甘油的深度开发和利用既是发展生物柴油工业的关键,也符合绿色化学的发展要求。近年来,甘油不仅作为重要的起始原料用于一些高附加值化学品的制备,而且因其独特的理化性质和易降解、生物相容性好等特性,在生物催化和绿色溶剂领域的应用研究日趋活跃。本文主要综述了甘油在工业微生物发酵、生物合成和绿色溶剂领域的研究进展,并就其应用中存在的一些问题,如甘油原料品质和微生物利用效率等进行分析,同时展望了甘油在生物催化领域的应用前景。     

生物法PTT纤维及原料研究进展

生物质材料在许多领域显现出广阔的应用前景。PTT纤维作为生物质纤维新品种,以其优良的性能、环保和可持续发展成为业内研究的新热点。系统介绍了国内外生物法1,3-丙二醇研究进展及生产概况,指出微生物法的能耗优势和技术瓶颈;详细综述了生物法PTT纤维制备、结构及性能等方面的研究进展,阐明了发展生物法纤维及其制品的有利形势。随着生物法1,3-丙二醇制备技术的日臻完善,长期制约PTT纤维发展的原料成本进一步降低,生物法PTT纤维的高速发展值得期待。     

丙烯醇反马氏水合制备1,3-丙二醇

1,3-丙二醇具有很高的经济价值，是合成纤维聚对苯二甲酸丙二酯的重要原料。基于甘油甲酸介入法获得的丙烯醇作为平台分子，通过丙烯醇与TiCl4-NaBH4反应，首次实现常温常压下1,3-丙二醇的制备, 为1,3-丙二醇的合成提供了一条新的路径。在最优条件下，1,3-丙二醇的产率68.73%，推测反应机理为：TiCl4和NaBH4发生反应，生成中间体 “BH3”，进而实现了丙烯醇反马氏水合制备1,3-丙二醇。     

双金属催化剂选择氢解甘油定向制备1,3-丙二醇：活性位、构效关系及机理

1,3-丙二醇是聚酯工业中最重要的单体之一。以甘油为原料,通过催化转化制备得到1,3-丙二醇具有重要的应用价值。本文对近年来甘油氢解制1,3-丙二醇的关键双金属催化剂研究进展进行综述,着重介绍了高效且颇具工业应用前景的Pt-W催化体系。通过综述Pt-W体系中具有不同微观结构和化学环境的W物种与Pt之间的相互作用及Pt-W双位点催化甘油氢解的构效关系,总结了原位生成的B酸活性物种对催化活性、选择性和稳定性的影响,讨论了原位B酸的来源及催化机制,最后对甘油选择氢解制1,3-丙二醇的催化剂发展进行了展望。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.