非MAO的茂钛均相催化体系催化苯乙烯间规聚合——[Cp~*TiMe_3]/[Ph_3C]~+[B(C_6F_5)_4]~-催化体系

非ＭＡＯ的茂钛均相催化体系催化苯乙烯间规聚合———［ＣｐＴｉＭｅ３］／［Ｐｈ３Ｃ］＋［Ｂ（Ｃ６Ｆ５）４］－催化体系许光学林尚安（中山大学高分子研究所广州５１０２７５）关键词茂钛络合物，茂金属催化剂，苯乙烯，间规聚苯乙烯间规聚苯乙烯（ｓＰＳ）由于具...     

聚苯乙烯固载聚乙二醇和邻苯二甲酰亚胺的N—烃基化反应中的…

本文报道了聚苯乙烯固载聚乙二醇作为相转移催化剂催化合成Ｎ－烃基邻苯二甲酰亚胺。在无水碳酸钾、无水氟化钾、乙腈和聚苯乙烯固载聚乙二醇４００或聚苯乙烯固载吡啶翁盐－聚乙二醇４００等作用下，合成了三种Ｎ－烃基邻苯二甲酰亚胺。     

新法浸铈氨合成催化剂

新法浸铈氨合成催化剂秦春玲关新新王茹胡平聂聪王文祥＊（郑州大学催化研究室郑州４５００５２）关键词熔铁催化剂，浸铈，氨合成，活性，强度１９９７－０３－１９收稿，１９９７－０８－１２修回国家自然科学基金资助课题铈作为氨合成催化剂的一种添加剂能提高催化活性...     

聚苯乙烯固载聚乙二醇在邻苯二甲酰亚胺的N-烃基化反应中的相转移催化作用

本文报道了聚苯乙烯固载聚乙二醇作为相转移催化剂催化合成Ｎ－烃基邻苯二甲酰亚胺。在无水碳酸钾、无水氟化钾、乙腈和聚苯乙烯固载聚乙二醇４００或聚苯乙烯固载吡啶盐一聚乙二醇４００等作用下，合成了三种Ｎ－烃基邻苯二甲酰亚胺。     

铽苯二甲酸同多核和异多核配合物的发光性能

铽苯二甲酸同多核和异多核配合物的发光性能阎冰张洪杰＊王淑彬倪嘉缵（中国科学院长春应用化学研究所稀土化学与物理开放实验室长春１３００２２）关键词铕，铽，镧，钆，钇，苯二甲酸，配合物，合成，发光性能１９９７－０６－２６收稿，１９９７－０８－２５修回国家自...     

Cu－Cr_2O_3催化合成丙烯酰胺中铬的助催化作用

Ｃｕ－Ｃｒ_２Ｏ_３催化合成丙烯酰胺中铬的助催化作用李晶明，杨博，周贵林，谢筱帆，李圭甲（中国科学院长春应用化学研究所长春１３００２２）关键词Ｃｕ－Ｃｒ＿２Ｏ＿３催化剂，丙烯腈，丙烯酰胺，催化水合，反应机理在还原铜催化剂中加铬可提高丙烯腈（ＡＮ）催化水...     

单茚钛与β-二酮钛催化苯乙烯间规聚合反应的性能

1986年Ishihara等[1]首次报道间规聚苯乙烯以来,人们对苯乙烯间规聚合的各种单茂钛类(包括单茚钛)催化剂进行了大量研究[2～5].这些单茂钛类催化剂聚合活性高,但合成复杂,催化剂总收率低.近年来,合成方法更为简便、聚合活性较高的新型非茂钛的研究开始引起人们的关注[6～8].至此苯乙烯间规聚合的催化剂大致分为两类,即单茂钛催化剂和非茂钛催化剂.这两大类催化剂的催化性能各有特点.对它们催化性能进行对比的研究报道尚不多见.我们自行设计并合成了单茚钛和β-二酮钛催化剂,对它们的催化性能进行了比较.     

[（t—BuCp）2YCH3]2的合成及其对甲基丙烯酸甲酯的催化聚合活性

［（ｔ┐ＢｕＣｐ）２ＹＣＨ３］２的合成及其对甲基丙烯酸甲酯的催化聚合活性扈晶余＊任劲松沈琪（中国科学院长春应用化学研究所稀土化学与物理开放实验室长春１３００２２）（苏州大学化学系苏州）关键词钇配合物，合成，聚合活性，甲基丙烯酸甲酯１９９６－０４－１８...     

两个β-二酮Co(Ⅱ)配合物[Co(β-diketonate)2(py)2]的合成和晶体结构

钴是生物学上重要的微量元素，它能在一些酶中代替锌，而不改变原来酶的活性犤１犦，钴的光谱和磁性是酶活性部位的有效探针犤２犦。钴催化剂是单活性中心催化剂犤３犦，同时又是很好的乙烯齐聚催化剂犤４，５犦。β－二酮是重要的催化剂原料，徐德民等犤６犦报道了含有β－二酮金属配合物催化剂制备间规聚苯乙烯与聚丙烯共混复合物。宓霞等犤７犦报道了含β－二酮钛非茂催化剂催化降冰片烯聚合。近年来，已报道了一些β－二酮的Co?配合物犤８～１０犦的晶体结构，本文报道两个β－二酮的Co?配合物的合成和晶体结构。１实验部分１．１配合…     

茂钛化合物／改性MAO催化剂制备聚丙烯—b—间规聚苯乙烯嵌 …

以五甲基环戊二烯基三苄氧基钛化合物「Ｃｐ＊Ｔｉ（ＯＢｚ）３」为主催化剂，改性甲基铝氧烷作助催化剂，采用单体顺序投入法，合成了聚丙烯－ｂ－间规聚苯乙烯嵌段共聚物。外加三异丁基铝可以使活性中心的氧化态由Ｔｉ（Ⅳ）还原为Ｔｉ（Ⅲ），从而提高苯乙烯共聚单体的转化率。实验表明此催化体系对共聚物的合成具有较高活性，适宜的茂钛化合物浓度可阻止活性中心被丙烯预聚物包埋。抽除残余丙烯气也可促进苯乙烯的共聚合。对聚合     

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.     

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.     

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.     

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.     

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.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.