薁磺酸钠结构确证的波谱学研究

用红外光谱、紫外吸收光谱、一维(1 H、13 C)和二维(1 H-1 H COSY、HMQC、HMBC)核磁共振光谱及质谱对薁磺酸钠进行结构确证。对所有的1 H-NMR和13 C-NMR谱进行了归属;讨论了红外吸收光谱峰所对应的官能团的振动形式,并详细分析了薁磺酸钠质谱图中主要碎片离子的裂解途径,还对样品进行了差热和热重分析。以上研究结果确证了薁磺酸钠的分子结构,并确证其经验分子式为C15H17NaO3S·1/2H2O。     

苯并咪唑萘酰亚胺类化合物的合成与结构确证

本文合成并分离提纯了1位和4位单取代的苯并咪唑萘酰亚胺(NBI)类化合物1~4,对化合物1的紫外-可见光谱、红外光谱、质谱、核磁共振谱(包括1H NMR、13C NMR、DEPT、1H-13C HSQC、1H-13C HMBC、1H-1HCOSY多种NMR技术)进行了详细解析,对其所有的1H和13C NMR信号进行了归属,并使用了GIAO和CSGT两种方法量化计算核磁位移,通过多种波谱学技术确证了化合物的结构。     

一种新的六氢嘧啶并嘧啶二酮衍生物的核磁共振分析

采用氢谱(1H NMR)、碳谱(13C NMR)、梯度场氢氢化学位移相关谱(1H-1H COSY)、梯度场质子检测异核单量子化学位移相关谱(HSQC)、梯度场质子检测异核多重键化学位移相关谱(HMBC)等多种NMR分析方法,确证了8a-对甲氧苯基-4,5-双(对氯苯基)六氢嘧啶[4,5-d]并嘧啶-2,7(1H,3H)-二酮的结构,对它的1H和13C NMR谱信号进行了归属,为其结构鉴定提供了重要依据。     

固体酸Amberlyst 15催化合成3-吲哚取代的苯酞类化合物

室温下, 以吲哚和邻甲酰苯甲酸为原料, 通过Amberlyst 15 (15 wt%)催化的傅-克反应, 高产率合成得到一系列3-吲哚取代的苯酞类化合物. 并通过1H NMR, 13C NMR, 红外光谱, 高分辨质谱确证了产物的结构.     

维库溴铵的核磁共振法分析

采用1H NMR,13C NMR,DEPT,H-HCOSY,HSQC,HMBC等多种核磁共振分析方法,确证了维库溴铵的结构,对它的1H和13C NMR谱信号进行了归属,并利用ROESY确定了其相对构型,为其结构鉴定提供了重要依据.     

含二氮杂萘酮单元双官能团化合物结构的波谱表征

在成功地合成了11个用于制备聚芳酰胺类聚合物的含二氮杂萘酮单元的双官能团化合物基础上,本实验用核磁共振波谱确定了各化合物的结构。用二维同核位移相关谱(gCOSY)、异核^13C-^1H-键相关谱(gHSQC)和异核^13C-^1H远程相关谱(gHMBC)完成了全部^1H和^13C NMR谱带的归属;首次报道了该系列衍生物的氢和碳原子的化学位移值。对其系列化合物的核磁共振波谱及红外光谱的特征进行了讨论。     

新药甲磺酸帕珠沙星的有机波谱分析

应用核磁共振波谱(NMR)、电子轰击质谱(EIMS)、紫外(UV)、红外(IR)吸收光谱等技术确证新药甲磺酸帕珠沙星的分子结构；解释了该结构在NMR、EIMS、IR、UV等谱图中的特征吸收峰、共振峰及特征离子的一一对应归属。     

微波促进5-芳亚甲基罗丹宁化合物的合成及晶体结构

以芳香醛和罗丹宁为原料,在乙酸钠/乙酸体系中经微波辐射反应得到一系列5-芳亚甲基罗丹宁,化合物结构经1H NMR和红外光谱确证。并对5-(4-硝基苯亚甲基)罗丹宁/四氢呋喃单晶进行了解析。     

氢化可的松氨基糖衍生物的合成

描述了一条简单有效的合成氢化可的松氨基糖衍生物的合成路线．实验中首先 将氢化可的松转化为琥珀酸酯衍生物2，葡萄糖、2—乙酰氨基葡萄糖、半乳糖、乳 糖及氨基葡萄糖盐酸盐转化成为相应的氨基糖7a-7d和12，然后2与7a-7d和12在 DCC的作用下通过酰胺键进行偶联，得到一系列氢化可的松糖氨基糖衍生物13a- 13e．上述目标化合物均为新化合物，其结构分别通过红外光谱(IR)、核磁共振波 谱(^1H NMR,^13C NMR)及HMRS进行了确证。     

咪喹莫特的波谱学数据与结构表征

对咪喹莫特的红外(IR)、紫外(UV)、质谱(MS)、氢-氢相关谱(^1H--^1H COSY)、碳氢相关谱(HMQC)、碳氢远程相关谱(HMBC)予以解析并进行了报道。对所有的^1H NMR、^13C NMR谱的信号进行了归属；讨论了质谱的主要碎片离子的可能的裂解方式和红外特征吸收峰所对应的官能团的振动形式。     

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.     

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.     

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.     

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.     

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%).