苯基或联苯基桥连双环戊二烯基铼羰基化合物的合成、结构及催化性能

两个单桥连的双环戊二烯（C₅Me₄H）E（C₅Me₄H）（E=C₆H₄,（C₆H₄）₂）分别与Re₂（CO）₁₀在均三甲苯中加热回流,得到了2个双核配合物（E）[（η⁵-C₅Me₄）Re（CO）₃]₂（E=C₆H₄（1）,（C₆H₄）₂（2））。通过元素分析、红外光谱、核磁共振氢谱和碳谱对配合物1和2的结构进行了表征,用X射线单晶衍射分析测定了配合物的结构。同时对2个配合物在芳香族化合物Friedel-Crafts酰基化反应中的催化活性进行了研究。     

基于两个取代四甲基环戊二烯基配体的金属羰基化合物的合成及晶体结构

配体[C₅Me₄HR][R=4-BrPh(1),(MeC₅H₃N)CH₂(2)]分别与Mo(CO)₆,Ru₃(CO)₁₂和Fe(CO)₅在二甲苯中加热回流,得到了6个双核配合物trans-[η⁵-C₅Me₄R]₂Mo₂(CO)₆(3,4),trans-[(η⁵-C₅Me₄R)Ru(CO)(μ-CO)]₂(5,6)和trans-[η⁵-(C₅Me₄R)Fe(CO)(μ-CO)]₂(7,8,).通过元素分析、红外光谱、核磁共振氢谱对配合物的结构进行了表征,并用X-射线单晶衍射法测定了配合物3,5,6和8的结构.     

2-苯亚胺官能化吲哚基铕-胺基配合物与芳基取代甲脒的反应性

2-（苯亚胺基次甲基）吲哚铕-胺基配合物[η¹：η¹-2-（C₆H₅NH=CH）C₈H₅N]₂Eu[N（SiMe₂）₂]（1）与二芳基取代甲脒（2,6-R₂C₆H₃N=CHNH（C₆H₃R₂-2,6）（R=ⁱPr（2）,Me（3））经过配体交换反应,分别得到了含吲哚基脒基铕配合物[η¹：η¹-2-（C₆H₅NH=CH）C₈H₅N]Eu[（η³-2,6-ⁱPr₂C₆H₃）N=CHN（C₆H₃ⁱPr₂-2,6）][N（SiMe₂）₂]（4）和含脒基的稀土铕配合物[（η³-2,6-Me₂C₆H₃）N=CHN（C₆H₃Me₂-2,6）]₂Eu[N（SiMe₂）₂]（5）。结果表明,脒基的位阻显著影响了吲哚基稀土金属胺基配合物与二芳基取代甲脒的配体交换反应。配合物4和5通过IR、元素分析和X射线单晶衍射分析进行了表征。     

2-苯亚胺官能化吲哚基铕胺基配合物与芳基取代甲脒的反应性

2-（苯亚胺基次甲基）吲哚铕胺基配合物[η¹：η¹-2-（C₆H₅NH=CH）C₈H₅N]₂Eu[N（SiMe₃）₂]（1）与二芳基取代甲脒（2,6-R₂C₆H₃N=CHNH（C₆H₃R₂-2,6）（R=ⁱPr（2）,Me（3））经过配体交换反应,分别得到了含吲哚基脒基铕配合物[η¹：η¹-2-（C₆H₅NH=CH）C₈H₅N]Eu[（η³-2,6-ⁱPr₂C₆H₃）N=CHN（C₆H₃ⁱPr₂-2,6）][N（SiMe₃）₂]（4）和含脒基的稀土铕配合物[（η³-2,6-Me₂C₆H₃）N=CHN（C₆H₃Me₂-2,6）]₂Eu[N（SiMe₃）₂]（5）。结果表明,脒基的位阻显著影响了吲哚基稀土金属胺基配合物与二芳基取代甲脒的配体交换反应。配合物4和5通过IR、元素分析和X射线单晶衍射分析进行了表征。     

受限几何型金属化合物的合成和催化性能

通过筛选合成路线和方法制备了3种桥联芴基-芳胺基化合物Me₂Si[（Flu）H]NH-2,6-ⁱPr₂C₆H₃（L¹）、Me₂Si[2,7-^tBu₂Flu（H）]NH-2,6-ⁱPr₂C₆H₃（L²）和Me₂Si[2,7-^tBu₂Flu（H）]NH-2,4,6-Me₃C₆H₂）（L³）,分别与第四族金属氯化物MCl₄反应制备了4种受限几何结构的茂金属化合物[Me₂Si（Flu）（N-2,6-ⁱPr₂C₆H₃）]ZrCl₂（THF）₂（1）、[Me₂Si（2,7-^tBu₂Flu）（N-2,6-ⁱPr₂C₆H₃）]TiMe₂（2）、[Me₂Si（2,7-^tBu₂Flu）（N-2,4,6-Me₃C₆H₂）]TiMe₂（3）和[Me₂Si（2,7-^tBu₂Flu）（N-2,6-ⁱPr₂C₆H₃）]HfMe₂（4）。化合物L¹~L³和1~4都经过谱学和元素分析表征,其中1~3还经过X射线衍射单晶结构确认。在AlⁱBu₃和（Ph₃C）⁺[B（C₆F₅）₄]-双助剂作用下研究了1~4分别催化乙烯/1-辛烯聚合性能,结果显示茂金属单活性中心作用特点以及1-辛烯的共聚效果。考察和比较了其它3种受限几何钛化合物[Me₂Si（C₅Me₄）（N^tBu）]TiCl₂、[Me₂Si（Ind）（N^tBu）]TiCl₂和[Me₂Si（Flu）（N^tBu）]TiMe₂的催化性能;讨论了1~4的结构和催化作用的关联性。     

芳基取代四甲基环戊二烯基铼羰基化合物的合成、晶体结构及催化性能

芳基取代的四甲基环戊二烯 C₅HMe₄Ar（Ar=Ph,4-CH₃Ph,4-OCH₃Ph,4-ClPh,4-BrPh） 分别与Re₂（CO）₁₀在二甲苯中加热回流,得到了5个单核配合物[（η⁵-C₅Me₄Ar）Re（CO）₃]（Ar=Ph （1）,4-CH₃Ph （2）,4-OCH₃Ph （3）,4-ClPh （4）,4-BrPh （5））。通过元素分析、红外光谱、核磁共振氢谱对配合物1~5的结构进行了表征,用X射线单晶衍射法测定了配合物的结构。同时,研究了这五种配合物在芳香族化合物Friedel-Crafts烷基化反应中的催化活性。     

芳基取代四甲基环戊二烯基铼羰基化合物的合成、晶体结构及催化性能

芳基取代的四甲基环戊二烯 C₅HMe₄Ar（Ar=Ph,4-CH₃Ph,4-OCH₃Ph,4-ClPh,4-BrPh） 分别与Re₂（CO）₁₀在二甲苯中加热回流,得到了5个单核配合物[（η⁵-C₅Me₄Ar）Re（CO）₃]（Ar=Ph （1）,4-CH₃Ph （2）,4-OCH₃Ph （3）,4-ClPh （4）,4-BrPh （5）]。通过元素分析、红外光谱、核磁共振氢谱对配合物1~5的结构进行了表征,用X射线单晶衍射法测定了配合物的结构。同时,研究了这五种配合物在芳香族化合物Friedel-Crafts烷基化反应中的催化活性。     

邻异丙硫基苯甲酰基和苯硫甲基铁衍生物的合成与反应

利用异丙基苯硫醚与丁基锂反应后,再依次与羰基铁和碘反应制得了碘桥双核邻异丙硫基苯甲酰基铁配合物[（o-ⁱPrS）C₆H₄COFe（CO）₂I]2,而苯甲硫醚类似的反应却仅得到单核苯硫甲基铁配合物C₆H₅SCH₂Fe（CO）₃I。当与亲核试剂作用时,这2个化合物表现出显著不同的反应活性。如双核配合物[（o-ⁱPrS）C₆H₄COFe（CO）₂I]2与2-吡啶硫醇钠（PySNa）反应得到单核配合物（o-ⁱPrS）C₆H₄COFe（CO）₂（SPy）,但单核配合物C₆H₅SCH₂Fe（CO）₃I与PySNa反应导致其分解。另一方面,单核配合物C₆H₅SCH₂Fe（CO）₃I与三苯基膦（PPh₃）反应得到羰基取代配合物C₆H₅SCH₂Fe（CO）₂（PPh₃）I,但是双核配合物[（o-ⁱPrS）C₆H₄COFe（CO）₂I]2类似的反应却导致其分解,没有获得可表征的化合物。所有新合成的化合物都通过了核磁与红外光谱的表征,它们的结构也获得了X射线单晶衍射的确证。     

邻异丙硫基苯甲酰基和苯硫甲基铁衍生物的合成与反应

利用异丙基苯硫醚与丁基锂反应后,再依次与羰基铁和碘反应制得了碘桥双核邻异丙硫基苯甲酰基铁配合物[（o-ⁱPrS） C₆H₄COFe（CO）₂I]₂,而苯甲硫醚类似的反应却仅得到单核苯硫甲基铁配合物C₆H₅SCH₂Fe（CO）₃I。当与亲核试剂作用时,这2个化合物表现出显著不同的反应活性。如双核配合物[（o-ⁱPrS） C₆H₄COFe（CO）₂I]₂与2-吡啶硫醇钠（PySNa）反应得到单核配合物（o-ⁱPrS） C₆H₄COFe（CO）₂（SPy）,但单核配合物C₆H₅SCH₂Fe（CO）₃I与PySNa反应导致其分解。另一方面,单核配合物C₆H₅SCH₂Fe（CO）₃I与三苯基膦（PPh₃）反应得到羰基取代配合物C₆H₅SCH₂Fe（CO）₂（PPh₃） I,但是双核配合物[（o-ⁱPrS） C₆H₄COFe（CO）₂I]₂类似的反应却导致其分解,没有获得可表征的化合物。所有新合成的化合物都通过了核磁与红外光谱的表征,它们的结构也获得了X射线单晶衍射的确证。     

烃基取代茚基钌羰基化合物的合成及晶体结构

配体C₉H₇R(R=CH₂CH₂CH₃ (1),CH₂(CH₃)₂ (2),C₅H₉ (3),CH₂C₆H₅ (4),CH₂CH=CH₂ (5))分别与Ru₃(CO)12在二甲苯或庚烷中加热回流,得到了6个双核配合物[(η⁵-C₉H₆R)Ru(CO)(μ-CO)]₂(R=CH₂CH₂CH₃ (6),CH₂(CH₃)₂ (7),C₅H₈ (8),CH₂C₆H₅ (9),CH₂CH=CH₂ (10))和[(η⁵-C₉H₆)(H₃CH₂C)CHCH(CH₂CH₃)(η⁵-C₉H₆)] [Ru(CO)(μ-CO)]₂ (11).通过元素分析、红外光谱、核磁共振氢谱对配合物的结构进行了表征,并用X-射线单晶衍射法测定了配合物6,9,10和11的结构.     

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%.     

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.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

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.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.     

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.     

Microwave-assisted copper-catalyzed stereoselective ring expansion of three-membered heterocycles with α-diazo-β-dicarbonyl compounds

Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular S_N2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively.