双齿有机磷功能化离子液体的合成及萃取钕性能研究

设计合成了双齿有机膦功能化离子液体(PFIL):1,3-双-[3-(二苯基膦酰基)丙基]咪唑双(三氟甲基磺酰基)亚胺盐([BPh2P(O)C3Im][NTf2]),其结构经FT-IR,31P NMR,1H NMR,13C NMR和HRMS确认。研究了双齿离子液体和单齿离子液体1-丙基-3-(3-二苯基膦酰基)丙基咪唑双(三氟甲基磺酰基)亚胺盐([C3Ph2P(O)C3Im][NTf2])对钕的萃取行为。考察了萃取时间、初始水相p H值、离子液体浓度、盐析效应等因素对萃取过程的影响。结果表明:萃取过程很快达到平衡;在弱酸性下萃取效果最好;萃取效率随着离子液体的浓度增大而增大;双齿功能化离子液体的萃取效率明显优于单齿离子液体;PFIL离子液体萃取稀土可能是中性络合机制。     

氧桥联双核钛、镍配合物的合成及催化制备双峰聚乙烯

从2种氧原子桥联双膦化合物双(2-二苯基膦苯基)醚(1a)和4,5-双(二苯基膦)-9,9-二甲基氧杂蒽(1b)出发,合成氧原子桥联双膦亚胺钛、镍配合物.在甲苯中回流条件下首先将化合物1a和1b与叠氮三甲基硅烷发生Staudinger反应,分别生成单和双膦亚胺前驱体2a和2b.然后再与环戊二烯基三氯化钛反应,脱去三甲基氯硅烷后得到相应膦亚胺过渡金属钛配合物3a和3b.单钛中心配合物3b进一步与乙二醇二甲醚溴化镍反应生成钛-镍异核双中心配合物4b.通过1H NMR,13C NMR,31P NMR,FTIR及元素分析对产物进行了表征,并利用X射线单晶衍射分析确定了配合物3a和3b的分子结构.在助催化剂甲基铝氧烷(MAO)作用下,配合物3a和4b对乙烯聚合均表现出较高的催化活性,其中双钛中心配合物3a催化得到较宽分子量的聚乙烯产物,而异核双中心配合物4b催化得到呈双峰分布的聚乙烯产物.     

新型手性季鏻盐的合成

以(S)-联萘酚为原料,与三氟甲磺酸酐反应制得联萘酚三氟甲磺酸酯(2);2在Ni(dppp)Cl2催化下与碘甲烷格氏试剂反应得2,2’-二甲基联萘(3);3经溴代反应得2,2’-二溴甲基联萘4;4与1,3-双(二苯基膦)丙烷(dppp)在甲苯中回流合成了一个新型的联萘酚衍生的双中心手性季鏻盐,其结构经1H NMR,31P NMR和FT-IR表征。     

铜(Ⅰ，Ⅱ)配合物的合成、结构与性质

在室温、有关配体存在下,利用金属铜粉和过氧化苯甲酰的氧化加成配位反应合成了四种铜(Ⅱ)配合物(配体分别为联吡啶、双二苯基膦乙烷、2-氨基吡啶、苯并咪唑)。同时又利用双齿有机膦配体(dppm=双二苯基膦甲烷,dppe=双二苯基膦乙烷,dppp=双二苯基膦丙烷,dppb=双二苯基膦丁烷)和金属铜盐的还原取代反应合成了四种一价铜(Ⅱ)配合物。通过元素分析确定了配合物的组成,经X射线四圆单晶衍射确定了配合物的分子结构,配合物的晶体结构由直接法和Fourier合成方法解出。利用电子光谱等手段研究了氧化加成配位和还原取代配位反应的机理。初步建立了一套简单有效的合成铜(Ⅰ,Ⅱ)配合物的新方法。     

(S)-5,5'-二氨基-2,2'-双二苯基膦基-1,1'-联萘的绿色合成

以2,2'-双二苯基磷基-1,1'-联萘[(S)-1]为原料,与H2O2经氧化反应制得(S)-2,2'-双二苯基磷氧基-1,1'-联萘[(S)-2];(S)-2经酸性树脂催化硝化制得(S)-5,5'-二硝基-2,2'-双二苯基磷氧基-1,1'-联萘[(S)-3)];(S)-3经Pd/C催化硝基氢化还原制得(S)-5,5'-二氨基-2,2'-双二苯基磷氧基-1,1'-联萘[(S)-4];(S)-4经HSi Cl3/PPh3还原制得(S)-5,5'-二氨基-2,2'-双二苯基膦基-1,1'-联萘,总产率65.6%,其结构经1H NMR,31P NMR和IR确证。     

金属配合物[MBr{(Ph2PCH2CH2)2C6H3}],[M=Pd(Ⅱ)、Pt(Ⅱ)]的合成及晶体结构

合成了一个新的双膦配位体2,6-双(二苯基膦乙基)溴苯,通过Pd     

周期有序介孔Rh(Ⅰ)有机金属催化剂用于水介质Heck反应的研究

以1,4-双(三乙氧基硅基)苯和2-(二苯基膦)乙基三乙氧基硅烷为混合硅源, 在表面活性剂作用下共缩聚得到二苯基膦功能化的有序介孔有机硅材料[PPh₂-PMO(Ph)], 通过配位作用将Rh(Ⅰ)有机金属催化剂固载到PPh₂-PMO上得到Rh(Ⅰ)-PPh₂-PMO(Ph)非均相催化剂, 并采用FTIR, NMR, XRD, TEM和氮气吸附等手段对催化剂进行了表征. 考察了该催化剂在水介质Heck反应中的催化性能, 实验结果表明, 所制备的Rh(Ⅰ)-PPh₂-PMO(Ph)具有与均相催化剂Rh(PPh₃)₃Cl相当的催化活性, 这主要归因于催化剂的高比表面积、有序介孔结构有利于提高Rh(Ⅰ)活性位的分散度, 减少了传质阻力; 同时PMO构建形成的微环境增强了表面疏水性, 有利于反应底物的吸附和扩散. 此外, 催化剂重复使用多次后活性仍没有明显降低.     

含二齿膦配体的二羰基铁化合物的制备及光诱导释放一氧化碳性能

一氧化碳释放剂(CORM)为CO在人体的精准输送提供了便利。为提高CORM的稳定性,以[Fe(CO)₄I₂]为前驱体,通过与二齿膦配体dppe、dppp、PNP(dppe=1,2-双(二苯基膦酰)乙烷,dppp=1,3-双(二苯基膦酰)丙烷,PNP=N-环己基-N-(二苯基膦酰)-1,1-二苯基膦胺(Ph₂PN(cyclohexyl)PPh₂)的配位取代反应制得了二齿膦二羰基铁化合物1~3,并利用FT-IR、UV-Vis、NMR、元素分析、单晶X射线衍射(化合物2、3)进行表征。通过红外光谱法研究了化合物1~3的降解释放CO性能,以评估其作为CORM的潜能。在二甲亚砜溶剂中、黑暗条件下这些化合物表现出良好稳定性;但在可见光(红光、绿光、蓝光)照射下,均可降解释放CO,其降解速率与光源的能量和化合物的结构有关。此外,在蓝光和绿光照射下,发现化合物1和2可从顺式构型向反式构型发生转化,而红光下因能量不足未见构型转化。     

1,2-二（二苯基膦）乙烷氯化钯(II)的合成及催化活性

以卤化钯（X=Cl、 Br、 I）为原料,乙腈为溶剂,与1,2-二（二苯基膦）乙烷反应,合成了1,2-二（二苯基膦）乙烷卤化钯[Pd(dppe)X₂, dppe=1,2-二（二苯基膦）乙烷],产率均高于96％,其结构经¹H NMR, XRD和元素分析确证。以Suzuki反应和Stille C—C偶联反应为模板反应,研究了Pd(dppe)Cl₂的催化活性。结果表明：Pd(dppe)Cl₂对2-氯噻吩和对甲氧基苯硼酸的Suzuki偶联反应、4,7-二氯苯并噻二唑核或其他含苯并噻二唑核的卤代芳烃与其他芳香核的锡试剂的Stille C—C偶联反应的催化转化率分别为80%~85%和52%~60%,催化活性优于四（三苯基膦）钯(70%~85%和43%~50%)。     

新型含膦聚合前体4-溴-3-(二苯基膦酰基)-1-(1,2,2-三氟乙烯氧基)苯的合成

以间氨基苯甲醚为原料,经重氮化、溴化、Pd催化偶联、氧化、1,2-二溴四氟乙烷氟烷基化、Zn粉还原脱卤消除等反应制得合成全氟环丁基芳基醚聚合物的新型含膦聚合前体——4-溴-3-(二苯基膦酰基)-1-(1,2,2-三氟乙烯氧基)苯,其结构经NMR和MS表征。     

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.