甲基苯基含氢硅油的合成及其热稳定性

以甲基含氢硅油为氢源,在浓硫酸催化下经水解共聚缩合合成了甲基苯基含氢硅油(1),其结构和热稳定性经1H NMR,FT-IR和TGA表征。结果表明,1失重5%的温度为337.42℃。     

在离子液体中合成多取代苯基异丙基醚

以1-甲基3-丁基咪唑四氟硼酸盐离子液体为反应介质,由多取代苯酚与2-溴丙烷反应合成了12个多取代苯基异丙基醚,其结构经1H NMR和IR确证.     

Enantiopure Trioxadecalin Derived Liquid Crystals: Influence of the Nature of the Phenyl Substituent on the Mesogenic Properties

Reaction of pseudo‐glucal 1 with Grignard reagents derived from 1‐bromo‐4‐(trimethylsilyloxy)benzene, 1‐bromo‐4‐methoxybenzene, 1‐bromo‐4‐methoxymethoxybenzene, 1‐bromo‐4‐dimethylaminobenzene, in the presence of a catalytic amount of NiCl₂(dppe), gives the corresponding unsaturated β‐C‐aryl glycosides 2. Desilylation and hydrogenation of 2 leads to β‐C‐aryl glycosides 4, which can be used as chiral precursor compounds in the synthesis of chiral liquid crystals. Combination of 4 with arylaldehydes leads to compounds 5–7, whereas reaction with p‐alkoxysubstituted phenylboronic acids gives the trioxaboradecalins 8–11. The mesogenic properties of these compounds are strongly influenced by the nature of the substituent on the phenyl ring in the molecule.     

Synthesis and Mesogenic Properties of Novel Terthiophene Derivatives

To develop novel oligothiophene‐based liquid crystals involving hydrogen bonding, new terthiophene derivatives containing a stearylamide group, N,N′‐distearyl‐5,5″‐dicyano‐2,2′∶5′,2″‐terthiophene‐4,4″‐dicarboxamide (DNC₁₈DCN 3T) and N,N′‐distearyl‐5,5′‐dipropyl‐2,2′∶5′,2′‐terthiophene‐4,4″‐dicarboxamide (DNC₁₈ DP3T), were designed and synthesized, and their thermal behavior examined. Although DNC₁₈DP3T did not exhibit liquid crystallinity, DNC₁₈DCN3T was found to form smectic A phase.     

The Synthesis and Some Physical Properties of New Laterally Substituted Phenyl Ethers Containing a trans-1,4-Disubstituted Cyclohexane Ring

The synthesis, liquid-crystal transition temperatures, and some physical properties of a variety of substituted phenyl ethers, most of which incorporate a lateral substituent, are reported. Many of the liquid crystals described exhibit nematic phases with negative dielectric anisotropy at elevated temperatures. The relationship between the nature of the lateral substituents and the observed liquid crystal phases and transition temperatures is discussed.     

荧光液晶分子α-氰基二苯乙烯衍生物的合成与光学性质

合成了液晶化合物α-氰基二苯乙烯衍生物(Z)-2-(4-十二烷基氨基苯基)-3-(4-十二烷氧基苯基)丙烯腈（T3）,化合物T3与其同系物(Z)-2-(4-氨基苯基)-3-(4-十二烷氧基苯基)丙烯腈（T2）的浓溶液和固体态在蓝绿光波段均有强的荧光发射。 热重分析数据表明,两个化合物均有好的热稳定性。 利用差式扫描量热分析和偏光显微镜研究了化合物T3的液晶性质,同时借助粉末XRD分析化合物T3的分子间排列方式,表明化合物T3形成近晶相液晶。     

Synthesis and Initial Thermal Characterization of Titanium Polyferrocene Ethers

Titanium polyferrocene ethers were synthesized by the inter-facial technique. Reaction is rapid and general. Synthesis can be effected by utilizing either NaOH or Et₃N but not without added base. Reactant molar ratio yield trends vary with the nature of the diol, indicative of the sensitivity of the system, at least to this variable. Decomposition to ca. 150°C occurs via a nonoxidative mode(s). Above 150°C, degradation occurs through an oxidative route(s) in air.     

Synthesis and Photochromic Properties of the Derivatives of Spiropyrans Containing a Mesogenic Group

The photochromic compounds continue to attract significant attention in view of their general applicability as optical information storage materials or switching devices1-2.In order to develop novel bifunctional and multifunctional materials,special attention has been paid to photochromic liquid crystalline compounds.Many studies have been carried out for all kinds of mixed systems,which are to dope small amounts photochromic compounds into liquid crystal3-4.However,the combination of the prop…     

Synthesis and Properties of New-type Troponoid Dithio-Crown Ethers

Troponoiddithio-crownethersareakindofnovelcomPounds.Takeshitaetall-'havereportedthesynthesisandmercurophilicpropertiesofthiskindofcompounds.lnthereportedcomPounds,thetWosulfuratomsareattached,partorall,tothetroponeringdirectly.Whetherthedithio-crownethersstillhaveselectiveandreversiblemercurysaltcaptUringabi1itywhenthetWosulfuratomslinktothebenZylic-mpepositionoftroponeringarousedourinterest.Herein,wewishtoreportthatfromthereactionof3,7-dichloromethyl-5-isopropyl-2-methoxytropone4withbis(mer…     

Synthesis and Complex-Forming Properties of N-Substituted Diazacrown Ethers

N-Substituted mono- and diazacrown ether with ethoxycarbonylmethyl, 7-phenyl-3,6-dioxaheptyl, p-methoxy, and p-nitrobenzyl groups in the side chain have been synthesized. Their reactions with alkali and alkaline-earth metals have been studied. Substituents affect the complex-forming ability of the base macrocycle by changing the basicity of the nitrogen atoms and coordinating with the complexing ion.     

A Facile One-pot Method for the Synthesis of Vinyl Ethers from 2-Hydroxyalkyl Phenyl Selenides

chloride instead of primary or secondary organic halide, only 21% isolated yield of 1-tert-butoxy-1-phenylethene was obtained. Obviously, t-butyl chloride would tend to mainly take place the elimination reaction rather than the substitution reaction under sodium alkylate. Scheme 1 R1OHPhSe R2R3CHX 2NaH/THFR1OPhSeCHR2R3R1 OCHR2R3H2O21 3 4 Table 1 Preparation of vinyl ethers from 2-hydroxyalkyl phenyl selenides Entry R1 R2R3X Product a Yield (%) b 1 C6H5 CH2=CHCH2Br 4a 83 …     

Synthesis, Mesogenic and Spectroscopic Properties of 2,5-Disubstituted Thiophene Derivatives

Two series of 2,5-disubstituted thiophene derivatives （series 1： 2,5-bis（p-alkoxyphenylethynyl）thiophene and series 2： 2,5-bis[p-（p-alkoxyphenylethynyl）（phenylethynyl）]thiophene） were synthesized and characterized by ^1H NMR, ^13C NMR, HRMS and elemental analysis. The relationship between the structure and the mesogenic and spectroscopic properties has been discussed. The results show that compounds 1a-1f all exhibited an enantiotropic nematic mesophase, which was confirmed by the polarized optical microscopy （POM）, differential scanning calorimeter （DSC） and variable temperature powder X-ray diffraction （PXRD）. In contrast, the extended conjugated analogues 2a-2b had no liquid crystal properties. As for the spectroscopic properties, incorporating more phenylethynyl units results in red-shifted absorption and emission spectra, greatly enhanced quantum efficiency.     

半芳香共聚酰胺的合成及热稳定性的研究

采用熔融缩聚法, 合成了长碳链聚酰胺(PA1212)与聚对苯二甲酰十二碳二胺(PA12T)的新型半芳香共聚酰胺, 用FTIR, 1H NMR和DSC对产物结构进行了表征. 通过热重分析研究了共聚酰胺在N2气氛中以不同升温速率β升温时的热降解过程与机理. 结果表明PA1212/12T的降解为一步过程, 随着β的增大, 平衡降解温度线性升高. 用Kissinger和Flynn-Wall-Ozawa两种方法求得PA1212/12T的热降解表观活化能分别为126.9和127.9 kJ/mol. 用Coats-Redfern法证明了PA1212/12T的热降解机理为Deceleration类型中的R1或F3降解机理.     

新型衍生化β-环糊精键合硅胶手性固定相的合成与性能研究

合成了苯基氨基甲酸酯全衍生化β-环糊精键合硅胶手性固定相.在正相色谱条件下,对系列2-(噻唑基)-α-氨基膦酸酯化合物进行了有效的手性拆分研究.结果表明,所有化合物都得到基线分离,对映异构体选择性α>1.2,为制备型液相色谱的手性拆分提供条件.     

Organic Synthesis Using Ptc-41: Synthesis of Cyclic Ethers Using Phase Transfer Catalysis

The reaction of (1) and (2) uith (3a)² 2nd (3b)³ under liquid-liquid (L-L) and solid-liquid (3-L) phase transfer (PT) conditions furnish the corresponding (4) and (6) respectively and the reaction of (2) with (5) gives dioxolane derivative (7)     

Synthesis and Enantiodifferentiating Properties of Chiral Aza Crown Ethers

Alkylation of 2-substituted (4S,5S)-4,5-bis(hydroxymethyl)-1,3-dioxolanes with 9-benzyl-1,17-diiodo-3,6,12,15-tetraoxa-9-azaheptadecane afforded new chiral aza and diaza crown ethers as a result of [1+1] and [2+2] additions. Their catalytic debenzylation gave the corresponding derivatives with a secondary amino group. The reaction of diethyl (+)-tartrate and diethyl (4S,5S)-1,3-dioxolane-4,5-diacetates with 1,8-diamino-3,6-dioxaoctane led to formation of chiral macrocyclic lactams which were reduced with lithium aluminum hydride. The resulting diaza crown ethers were tested for enantioselectivity in complex formation with L- and D-valine methyl ester by the potentiometric method. In most cases, the aza crown ethers showed better enantioselectivity than their oxygen analogs.     

Hyperbranched Poly(aryleneethynylene)s: Synthesis,Thermal Stability and Optical Properties

Summary: Alkyne copolycyclomerizations of aromatic diynes 2,7‐bis(4‐ethynylphenylethynyl)‐9,9‐dihexylfluorene ( I ) and 1,4‐bis(4‐ethynylphenylethynyl)benzene ( II ) with an aliphatic monoyne 1‐dodecyne ( A ) were effected by CpCo(CO)₂ hv in THF, producing hyperbranched poly(aryleneethynylene)s ( 1 and 2 ) of high molecular weights ( up to 4.4 × 10⁴ Da) in high isolation yields (up to 97%). The polymers possessed outstanding thermal stability and emitted strong deep blue light of ≈400 nm when their solutions were photoexcited. The polymers effectively limited the light of a 532 nm laser, with the performance of 2 being better than that of C₆₀, a well‐known optical limiter, under similar linear transmittance.

The structure of hyperbranched poly(aryleneethynylene).