新型大位阻取代茂钛,锆化合物的合成及其谱学性质

通过１－环庚烯基锂与６，６－二烷基富烯发生环外双键的加成反应形成的大取代茂锂试剂与ＭＣｌ４（Ｍ＝Ｔｉ，Ｚｒ）反应，合成了１２个含或不含手性碳的大位阻取代茂金属有机化合物，并研究了它们的１ＨＮＭＲ，ＥＩＭＳ和ＩＲ．     

6,6—二烷基富烯与苄基钠的反应研究：取代茂钛,锆化合物…

苄基钠与６，６－二烷基富烯及６，６－ｎ亚甲基富烯（ｎ＝４，５，６）皆发生富烯环外双键的加成反应。产生的取代环戊二烯基负离子与ＴｉＣｌ４、ＺｒＣｌｒ及（ＣｐＴｉＣｌ２）２Ｏ络合，合成出２２种新的含或不含手性碳取代茂铁、锆化合物。讨论了反应机理及＾１Ｈ ＮＭＲ谱。     

6，6－二烷基富烯与苄基钠的反应研究──取代茂钛、锆化合物的合成

苄基钠与６，６－二烷基富烯及６，６－ｎ亚甲基富烯（ｎ＝４，５，６）皆发生富烯环外双键的加成反应。产生的取代环戊二烯基负离子与ＴｉＣｌ_４、ＺｒＣｌ_４及（ＣｐＴｉＣｌ_２）_２Ｏ络合，合成出２２种新的含或不含手性碳取代茂钛、锆化合物。讨论了反应机理及~１ＨＮＭＲ谱。     

经分子内Mannich反应合成3,6—二取代—5,6—二氢—s—三唑并（3,4—b）—1, …

３－取代基－４－氨基－５－巯基－１，２，４－三唑在微量酸催化下与取代芳香醛经分子内Ｍａｎｎｉｃｈ反应合成了２９个新的３，６－二取代－５，６－二氢－ｓ－三唑并（３，４－ｂ）－１，３，４－噻二唑啉类化合物，其结构经元素分析，ＩＲ和＾１ＨＮＭＲ进行确证，并讨论了反应的立体选择性。     

Synthesis of 3,6-Disubstituted 5,6-Dihydro-s-triazolo [3,4-b]-1,3,4-thiadiazolidines through the Intramolecular Mannich Reaction

３－取代基－４－氨基－５－巯基－１，２，４－三唑在微量酸催化下与取代芳香醛经分子内Ｍａｎｎｉｃｈ反应合成了２９个新的３，６－二取代－５，６－二氢－ｓ－三唑并［３，４－ｂ］－１，３，４－噻二唑啉类化合物，其结构经元素分析、ＩＲ和１ＨＮＭＲ进行确证，并讨论了反应的立体选择性。     

有机环四硅氧烷液晶的合成及其相变行为

两种环四硅氧烷分别和６种液晶基元化合物（Ｍ１－６）反应，合成了６种仅含１个介晶侧基的环四硅氧烷（１－６）。它们的化学结构已由＾１ＨＮＭＲ、ＩＲ和元素分析证实，借助ＤＳＣ和偏光显微镜观察研究了１２个化合物的相变行为。     

2－羟基2＇烷氧基－1，1＇－联萘化合物的~1HMNR研究

研究了２－羟基－２＇－异丙氧基－１。１－联萘（３）等联萘化合物的~１ＨＮＭＲ谱或ＣＯＳＹ谱。此类化合物因２及２＇位取代基不同，两个萘环上同位质子不再等价，萘环质子峰增至１２组。化合物３~１ＨＮＭＲ谱峰的归属表明，萘环环电流各向异性对另一萘环质子的屏蔽作用与作者早期研究结果［１］一致。２（或２＇）位取代基上的质子的化学位移也与另一萘环平面相对位置有关。     

2—羟基2‘烷氧基—1,1’—联萘化合物的^1HMNR研究

研究了２－羟基－２＇－异丙氧基－１，１－联萘（３）等联萘化合物＾１Ｈ ＮＭＲ谱或ＣＯＳＹ谱，此类化合物因２及２＇位取代基不同，两个萘环上同位质子不再等价，萘环质子峰增至１２组。化合物３＾１ＨＮＭＲ谱峰的归属表明，萘环环电流各向异性对另一萘环质子的屏蔽作用与作者早期研究结果一致。２（或２＇）位取代基上的质子的化学位移也与另一萘环平面相对位置有关。     

3-吡唑基-6-取代均三唑并[3,4-b]-1,3,4-噻二唑的合成及生物活性

以１－甲基－３－乙基（－４－氯）－５－吡唑甲酰肼作原料，经两步得到４－氨基－３－（１－甲基－３－乙基（－４－氯）－５－吡唑基）－１，２，４－三唑－５－硫酮（３），３再与取代羧酸反应，得到一系列３－（１－甲基－３－乙基（－４－氯）－５－吡唑基）－６－取代均三唑并［３，４－ｂ］－１，３，４－噻二唑（４、５、６）．元素分析、１ＨＮＭＲ、ＩＲ和ＭＳ确定了它们的结构．初步生测结果表明：３具有植物生长调节活性，４ｂ、４ｄ、６具有杀菌活性．     

含吡啶环联苯型[33]环系和含中心功能基[22]环系冠醚化合物的合成

以２，６－二溴甲基吡啶、４－甲基－２，６－二溴甲基苯甲醚为前体分别与２，２′－二羟基联苯反应合成新型的含吡啶环联苯型［３３］环系和含中心功能基［２２］环系冠醚化合物。其结构经元素分析、ＩＲ、１ＨＮＭＲ、ＭＳ等确证     

大取代环戊二烯基铪的合成与结构分析

芳基锂与6, 6-二烷基富烯发生加成反应, 生成含或不含手性碳的大位阻取代环戊二烯基负离子。用四氯化铪配合物, 合成了19个大取代茂铪化合物。讨论了其^1H NMR。化合物[(CH3)2C(C6H4-p-CH3)-C5H4]HfCl2经X射线衍射分析。晶体为单斜晶系, 空间群为I2/a, 晶胞参数a=2.2263(7), b=0.6674(2), c=2.5379(9)nm,β=135.13(3)°, R=0.058, Rw=0.069。结构研究表明, 取代基的引入, 使得茂环发生变型, 最大扭曲角为8.45°。     

Asymmetric Epoxidation of Unfunctionalized Olefins Using Novel Chiral Dihydroisoquinolinium Salts as Organocatalysts

Russian Journal of Organic Chemistry - Two new non-racemic chiral dihydroisoquinolinium salts with N-substituents bulkier than a methyl group have been synthesized from (1S,2R)-norephedrine. These...     

大取代茂钛,锆,铪,铁化合物的合成与结构分析

通过芳基锂与6,6-二烷基富烯发生环外双键的加成反应,形成的取代环戊二烯基阴离子与FeCl_2、MCl_4(M=Ti,Zr,Hf)及(CpTiCl_2)_2络合,合成出16个含或不含手性碳取代茂金属化合物。对其~1H NMR光谱进行了研究。     

大取代茂钼化合物的合成与结构分析

利用芳基锂与6,6-二烷基富烯发生加成反应,制得大取代环戊二烯基负离子.用六羰基钼配位,合成出13个钼-钼双核及5个钼-卤素单核羰基化合物.研究了其IR、^1HNMR、^95MoNMR.测定了[(CH~3)~2C(m-CH~3C~6H~4]Mo(CO)~3Br(1)的晶体结构.该晶体属于单余晶系,晶胞参数为a=1.175(3),b=1.4196(2),c=1.1894(4)nm,β=118.03(2)°,Ⅴ=1.75134nm^3.Z=4,D~0=1.733g/cm^3,F(000)=904,μ=30.0cm^-1,R=0.039,R~W=0.050,空间群为P2~1/α.     

Copolymerization of 2-Hydroxyethyl Methacrylate with Alkyl Methacrylates. Part IV. Mechanical Properties and Biocompatibility

Mechanical properties of copolymers of 2-hydroxyethyl methacrylate with methyl methacrylate, ethyl methacrylate, and n-butyl methacrylate have been investigated using an Instron tensile tester. It was observed that the overall mechanical properties decrease as the ester alkyl group of alkyl methacrylate becomes bulkier. Biocompatibility of the copolymers was also investigated by implanting them subcutaneously in rats.     

Organotin polymers—II.Copolymerization parameters for tributyltin methacrylate with methyl acrylate,ethyl acrylate,butyl acrylate and acrylonitrile

Copolymerizations of tributyltin methacrylate (M₁) with methyl acrylate, ethyl acrylate, n-butyl acrylate and acrylonitrile were carried out in solution at 70° using azobisisobutyronitrile as initiator. Copolymer compositions were determined by tin analysis; monomer reactivity ratios were calculated by Fineman-Ross and Kelen-Tüdös methods. The reactivities of acrylic esters decrease as the alkyl group becomes bulkier. Azeotropic copolymers could be formed from tributyltin methacrylate with butyl acrylate and with acrylonitrile. The structures of M₁ and its azeotropic copolymers have been investigated by infrared spectroscopy.     

Synthesis and supramolecular assemblies of bipolar archaeal glycolipid analogues containing a cis-1,3-disubstituted cyclopentane ring

Unsymmetrical archaeal tetraether glycolipid analogues 1-2 incorporating a 1,3-disubstituted cyclopentane ring into the bridging chain have been synthesized. The cyclopentane has been introduced with a totally controlled cis configuration, either into the middle of the aliphatic chain or at three methylene groups from the glycerol unit linked to the bulkier disaccharide residue. Freeze-fracture and cryotransmission electron microscopy experiments clearly demonstrated unprecedented glycolipid supramolecular organizations involving two-by-two monolayer associations coupled with interconnection and fusion phenomena. Furthermore, a significant difference in the hydration properties and in the lyotropic liquid crystalline behavior of bipolar lipids 1-2 was found depending on the position of the cyclopentane residue.     

The first complexes and cyclodimerisations of methylphosphaalkyne (P[triple bond]CMe)

The first complexes and cyclodimerisations of methylphosphaalkyne, P[triple bond]CMe, are reported to arise from its reactions with a range of platinum(0) complexes and [W(CO)5(THF)]. A number of differences between the chemistry of this phosphaalkyne and that of its bulkier analogues have been highlighted and explained on steric grounds.     

Solution processable indoloquinoxaline derivatives containing bulky polyaromatic hydrocarbons: synthesis, optical spectra, and electroluminescence

New hybrid materials featuring the dipolar fragment 6H-indolo[2,3-b]quinoxaline attached to the bulkier polyaromatic hydrocarbons such as fluoranthene, triphenylene, or polyphenylated benzene have been synthesized by a two-step procedure involving Sonogashira and Diels-Alder reactions. They were characterized by absorption, emission, electrochemical, thermal, and theoretical investigations. The electronic properties of the compounds were dominated by the 6H-indolo[2,3-b]quinoxaline chromophore, and the incorporation of polyaromatic hydrocarbons reduces the chances of nonradiative deactivation processes associated with the excited state and improves the emission properties. The compounds displayed cyan emission with moderate quantum efficiency when excited at the absorption maximum. All of the compounds exhibited an irreversible reduction process corresponding to the addition of electron at the quinoxaline segment. They showed moderate thermal stability and glass transition temperature greater than 100 °C. The presence of rigid 6H-indolo[2,3-b]quinoxaline and bulkier polyaromatic hydrocarbon segments enhances the thermal stability and glass transition temperature significantly. Finally, the dyes were successfully applied as an electron-transporting and emitting layer in multilayered organic light-emitting diodes comprising a N,N'-bis(l-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4,4'-diamine hole-transporting layer. The cyan emitting devices were characterized by moderate device performance parameters.     

Sorption of phenols by single and mixed cyclodextrin polymers

Cyclodextrin (CD) hydrogels were synthesized by a crosslinking reaction with the same cyclodextrin/epichlorohydrin mole ratio (1/11) using αCD, βCD, γCD, and 50:50 mixtures of α/βCD and β/γCD. In order to investigate the sorption capacity of these hydrogels to different solutes, five model molecules have been selected: phenol, 3-nitrophenol, 4-nitrophenol, 1-naphthol, and the antiinflamatory drug diflunisal. The amounts sorbed have been related to the different affinities of the solutes. 1-naphthol shows the highest affinity for these polymers, especially in the case of sorbents containing βCD. The sorption is considerably poorer for phenol than for its nitro derivatives. The two structural isomers 3- and 4-nitrophenol show significant differences in their affinities towards αCD, βCD and α/βCD. Finally, in the case of diflunisal, a bulkier model molecule, remarkable differences were found on the sorption behaviour by polymers whose cyclodextrins have a similar affinity for this solute (βCD, γCD, and β/γCD).