合成双分子膜的研究 Ⅰ.单链1,5取代萘刚性生色基的双亲化合物的合成及其在稀溶液中的自组织规律

本文首次报道了系列单链、1,5取代萘刚性生色基团的两亲化合物C_nNaph(1,5)C_6N~+(n=16,12,10,8,6和4)的合成.用电镜、~1H NMR和DSC分别观察了该系列化合物在稀溶液中的聚集形态、聚集体内分子运动和物相变化.结果表明:当n≥8时,该系列双亲化合物在稀溶液中自组织成双层结构的囊泡,泡壁为双分子膜.n=6时,囊泡形状不完整.n=4时,聚集体无确定形态.     

合成双分子膜的研究I. 单链1, 5取代萘刚性生色基的双亲化合物的合成及其在稀溶液中的自组织规律

本文首次报道了系列单链、1, 5取代萘刚性生色基团的两亲化合物C~nNaph(1,5)C~6N^+(n=16, 12, 10, 8, 6和4)的合成。用电镜、1^H NMR和DSC分别观察了该系列化合物在稀溶液中的聚集形态、聚集体内分子运动和物相变化。结果表明: 当n≥8时, 该系列双亲化合物在稀溶液中自组织成双层结构的囊泡, 泡壁为双分子膜。n=6时, 囊泡形状不完整。n=4时, 聚集体无确定形态。     

合成双分子膜的研究I. 单链1, 5取代萘刚性生色基的双亲化合物的合成及其在稀溶液中的自组织规律

本文首次报道了系列单链、1, 5取代萘刚性生色基团的两亲化合物C~nNaph(1,5)C~6N^+(n=16, 12, 10, 8, 6和4)的合成。用电镜、1^H NMR和DSC分别观察了该系列化合物在稀溶液中的聚集形态、聚集体内分子运动和物相变化。结果表明: 当n≥8时, 该系列双亲化合物在稀溶液中自组织成双层结构的囊泡, 泡壁为双分子膜。n=6时, 囊泡形状不完整。n=4时, 聚集体无确定形态。     

疏水-亲脂作用对反应性的影响 Ⅲ.环糊精对碳氟表面活性剂的熵驱动包结以及亲脂作用对形成糖淀粉型包结物的贡献

用表面张力-浓度曲线法系统地研究了环糊精(CD)和羧甲基糖淀粉钠(Na-CMA)与H(CF_2)_(12)CO_2K(1),Cl(CF_2)_nCH_2CH_2N~+(CH_3)_3I~-[n=8(3),10(5)]和相应的碳氢表面活性剂(24和6)的相互作用。由于几何尺寸的限制,碳氟表面活性剂不能与α-CD形成包结络合物,但3与β-CD形成的包结络合物的稳定性远大于相应的碳氢受物4、3与β-CD的相互作用是熵驱动过程,而C_(12)H_(25)N~+(CH_3)_3I~-(6)则是焓有利的。与具有“预组织化”内穴的CD不同,糖淀粉的包结是与大分子从线团到螺旋构象变化的协同过程,由于缺乏宿主-受物间的亲脂相互作用,Na-CMA不能与所有的碳氟受物形成包结络合物。     

[2,4—CH3）2C5H5]2TiCO的合成及结构

合成了开环夹心羰基化合物[2,4-(CH_3)_2C_5H_5]_2GCO,得到了该分子的单晶结构,[2,4-(CH_3)_2C_5H_5]_2TiCO晶体属于正交晶系,P2_12_12_1空间群,晶胞参数a=1.0078(5)nm,b=1.1909(8)nm,c=1.1946(5)nm,b=1.4337(13)nm~3,Z=4,R=0.054。单晶结构表明该分子为平行覆盖型开环夹心化合物,用EHMO方法计算了[2,4-(CH_3)_2C_5H_6]_2TICO的电子结构。     

1-丁基-3-甲基咪唑甲基磺酸盐水溶液中酚型木质素单体溶解的二维相关红外光谱分析北大核心CSCD

当离子液体(IL)水溶液—1-丁基-3-甲基咪唑甲基磺酸盐([C_(4)C_(1)im]CH_(3)SO_(3))的摩尔分数x_(IL)=0.20时,酚型木质素单体模型化合物2,6-二甲氧基苯酚(2,6-DMP)的溶解度最高。这一现象与木质素溶解规律相似。利用二维相关红外光谱(2D-IR)研究2,6-DMP在[C_(4)C_(1)im]CH_(3)SO_(3)水溶液中溶解过程,以帮助深入理解木质素在IL水溶液中溶解机制。以x_(IL)变量的2D-IR分析结果表明,x_(IL)=0.02~0.20条件下IL加入破坏水的弱氢键结构,IL阴阳离子以水合离子对形式存在,疏水性2,6-DMP与[C_(4)C_(1)im]+和CH_(3)SO_(3)−同时发生相互作用,促进2,6-DMP溶解;x_(IL)=0.20~1.0条件下,IL形成致密离子簇结构,不利于2,6-DMP与IL阴阳离子相互作用。以2,6-DMP摩尔分数(x_(DMP))为变量的分析结果表明,加入2,6-DMP对IL结构影响小,而对水的微观结构影响大。对于具有离子对结构的IL水溶液(x_(IL)=0.10),水优先与CH_(3)SO_(3)−作用;对于具有离子簇结构的IL水溶液(x_(IL)=0.60),水优先形成自缔合小水簇结构。IL水溶液微观结构影响IL-水与2,6-DMP之间相互作用和2,6-DMP溶解特性,同时2,6-DMP溶解也导致IL水溶液的微观结构变化。     

单链2,7-取代萘刚性生色基双亲化合物的合成及其在稀溶液中的自组织

合成了系列单链含2,7-取代萘刚性生色基的双亲化合物C_nNaph(2,7)C₆N⁺(n=4,7,10,12,16),分别用透射电镜、¹HNMR和DSC观测了该系列双亲物在稀溶液中的聚集形态,研究了聚集体内的分子运动和凝胶态到液晶态的相变.结果表明,当尾链n≥7时,该系列化合物在稀溶液中自组织成双分子层排列的囊泡,当n=4时聚集体无确定形态.     

POLYMERIZATION OF ISOBUTYL VINYL ETHER CATALYSED BY DINUCLEAR HALF-TITANOCENES

Polymerization of isobutyl vinyl ether(IBVE)has been studied with mononuclear half-titanocene,CpTiCl_3[1]and dinuclear half-titanocenes,[(C_5H_4)_2(CH_2)_n][(TiCl_3)_2][2(n=3),3(n=6)],and[(C_5H_4)_2(CH_2)_n[(TiCl_2OR_2](R=2,6- diisopropylphenoxyl)[4(n=3),5(n=6)],in the presence of methyl aluminoxanes(MAO)as cocatalyst in methylene chloride.The influences of the length of polymethylene brigde and the substitution of aryloxy group at the metal center have been investigated at three polymerization temperatu...     

钼铁硫原子簇化合物的合成与结构化学研究 Ⅱ.以Fe(SR)_6为桥的双类立方烷化合物的合成及(Et_4N)_4[Mo_2Fe_7S_8(SC_6H_4CH_3-m)_(12)]·2THF的晶体结构

在乙腈溶液中(Et_4N)_2[Fe_4(SR)_(10)]与(Et_4N)_2[MoS_4]反应半小时生成对氧极为敏感的系列黑色晶状化合物(Et_4N)_4[Mo_2Fe_7S_8(SR)_(12)(R=C_6H_5,1;R=C_6H_4CH_3-m,2;R=C_6H_4CH_3-o,3;R=C_6H_4CH_3-p,4).2·2THF晶体的分子量为2982.8,属单斜晶系;空间群为P2_1/n;α=18.022(2),b=18.375(2),c=22.254(3)A;β=71.04(1)°;V=6969(2)A~3;D_(?)=1.424g·cm~(-3);Z=2;F(000)=3108.晶体结构用直接法解出,修正至R=0.064.2.2THF中Mo…Mo′距离为7.234A.     

新的双金属簇原子大分子已合成

伊利诺大学B.K.Teo教授的研究小组最近合成了一种原子数仅次于1986年米兰大学G.Longoni的金属簇化合物,并确定了其结构。该化合物的化学式为[CH_3(C_6H_4_3P]_(12)Au_(1?)Ag_(20)Cl_(14),Longoni合成的分子化学式为[Pt_6Ni_(38)(CO)_(43)H_(6-n)]~(n-)(n=4,5)。在Teo     

Micelle to vesicle transitions of N-dodecyl-1, ω-diaminoalkanes: effects of pH, temperature and salt

The self-assembly behavior of pH-sensitive amphiphiles N-dodecyl-1, 2-diaminoethane (C12N2N), N-dodecyl-1, 3-diaminopropane (C12N3N) and N-dodecyl-1, 4-diaminobutane (C12N4N) has been studied in aqueous solutions. Light scattering, viscosity and cryo-transmission electronic microscopy (cryo-TEM) results revealed that the aggregates transferred from spherical micelles to vesicles (MVT) via wormlike micelles as the pH was gradually varied from acidic to basic conditions. pH-dependent zeta potential and (1)H NMR studies confirmed these transitions. Interestingly, the formed wormlike micelles could transform into vesicles upon heating, which was studied by cryo-TEM, light scattering and viscosity techniques in detail. It is concluded that the pH and thermal MVT are a general phenomenon in all three amphiphiles investigated. Furthermore, NaCl induced a wormlike micelle to vesicle transition was also observed in C12N2N solution.     

1H NMR study on pre-micellization of quaternary ammonium gemini surfactants

Two quaternary ammonium Gemini surfactant series, 12-s-12, ([C(12)H(25)N+ (CH(3))(2)](2)(CH(2))(s).(2)Br(-)) and 14-s-14 ([C(14)H(29)N(+)(CH(3))(2)](2)(CH(2))(s).(2)Br(-)), where s = 2, 3, and 4, have been studied by the use of (1)H NMR in aqueous solution at concentrations below their critical micelle concentrations (CMC) at 25 degrees C. The appearance of a second set of peaks for the 14-s-14 series and the changes in chemical shifts, line widths, and line shapes of the 12-s-12 series with increasing concentration below the CMC are interpreted as evidence for the formation of premicelle aggregates (oligomers) that appear at approximately one-half their CMC values. Self-diffusion coefficients (D) and transverse relaxation times (T(2)) have also been detected and support the results obtained by (1)H NMR.     

Effect of the spacer length on the association and adsorption behavior of dissymmetric gemini surfactants

A series of dissymmetric gemini surfactants with the general formula [C12H25(CH3)2N(CH2)sN(CH3)2C14H29]Br2 designed as 12-s-14, where s=2, 6, and 10, were synthesized and their physicochemical properties investigated. The effect of spacer length on Krafft temperature, adsorption at the air/solution interface, and association in aqueous solution was studied by tensiometry, conductometry, and cryo-transmission electron microscopy. The Krafft temperature was found to increase linearly with spacer length. In the submicellar concentration range the dissymmetric 12-s-14 surfactants display ion pairing and premicellar association. Adsorption at air/solution interfaces and micellization in aqueous solution are similar to the behavior of their symmetric counterparts and depend strongly on spacer length.     

碳氟醇对阳离子表面活性剂表面活性及胶团反离子结合度的影响

用表面张力及电动势法研究了C₁₀H₂₁N(CH₃)3Br、C₁₂H₂₅N(CH₃)3Br与C₃F₇CH₂OH混合水溶液的表面与胶团性质。结果表明,对于阳离子表面活性剂,C₃F₇CH₂OH的加入一方面增加表面活性,另一方面降低胶团反离子结合度。后者不同于阴离子表面活性剂/C₃F₇CH₂OH混合体系,可归因于C₃F₇CH₂OH略有酸性,因而具备一些类似阴离子表面活性剂的性质。     

Dinitrogen activation, partial reduction, and formation of coordinated imide promoted by a chromium diiminepyridine complex

Reduction of {2,6-[2,6-(i-Pr)2PhN=C(CH3)]2(C5H3N)}CrCl (3) with NaH afforded the dinuclear dinitrogen complex {[{2,6-[2,6-(i-Pr)2PhN=C(CH3)]2(C5H3N)}Cr(THF)]2(mu-N2)}.THF (5). Reaction carried in exclusion of dinitrogen afforded instead deprotonation of the ligand with the formation of {2-[2,6-(i-Pr)2PhN=C(CH3)]-6-[2,6-(i-Pr)2PhNC=CH2](C5H3N)}Cr(THF) (4). Further reduction of 5 with NaH yielded a curious dinuclear compound formulated as [{2,6-[2,6-(i-Pr)2PhN=C(CH3)]2(C5H3N)}Cr(THF)][{2-[2,6-(i-Pr)2PhN=C(CH3)]-6-[2,6-(i-Pr)2PhNC=CH2](C5H3N)}Cr(THF)](mu-N2 H)(mu-Na)2 (6) containing two sodium atoms only bound to the dinitrogen unit and the pi systems of the two diiminepyridine ligands. Subsequent reduction with NaH triggered a complex series of events, leading to the formation of a species formulated as {2-[2,6-(i-Pr)2PhN=C(CH3)]-6-[2,6-(i-Pr)2PhNC=CH2](C5H3N)}Cr(mu-NH)][Na(THF)] (7) on the basis of crystallographic, spectroscopic, isotopic labeling, and chemical degradation experiments.     

二(β-羟亚胺)二氯化钛配合物的合成及催化乙烯聚合

报道了3个β-羟亚胺配体(2,6-^emPr₂C₆H₃)N＝C(Ph)CH₂CH(Ph)OH(1a), (2,6-^emPr₂C₆H₃)N＝C·(Ph)CH₂C(Ph)₂OH(1b)和(2,6-^emPr₂C₆H₃)N＝C(Ph)CH₂C(C₁₂H₈)OH(1c)及其二(β-羟亚胺)二氯化钛配合物[(2,6-^emPr₂C₆H₃)N＝C(Ph)CH₂CH(Ph)O]₂TiCl₂(2a), [(2,6-^emPr₂C₆H₃)N＝C(Ph)CH₂C(Ph)₂O]₂·TiCl₂(2b)和[(2,6-^emPr₂C₆H₃)N＝C(Ph)CH₂C(C₁₂H₈)O]₂TiCl₂(2c)的合成, 并对其结构进行了表征. 在助催化剂甲基铝氧烷(MAO)作用下, 以化合物2b为主催化剂, 研究了Al/Ti摩尔比、 反应时间、 温度和聚合压力等对乙烯聚合的影响, 发现该催化体系在较宽的反应条件下均可得到很高分子量的聚乙烯, 熔点均在140℃左右. 以化合物2a~2c为主催化剂对乙烯进行催化聚合, 发现在β碳位上取代基的立体位阻对催化剂活性有很大影响. 当化合物2b上引入2个苯基取代基时, 催化剂显示出最佳催化活性.     

Multiple pathways for dinitrogen activation during the reduction of an Fe Bis(iminepyridine) complex

Reduction of the bis(iminopyridine) FeCl(2) complex {2,6-[2,6-(iPr)(2)PhN=C(CH(3))](2)(C(5)H(3)N)}FeCl(2) using NaH has led to the formation of a surprising variety of structures depending on the amount of reductant. Some of the species reported in this work were isolated from the same reaction mixture, and their structures suggest the presence of multiple pathways for dinitrogen activation. The reaction with 3 equiv of NaH afforded {2-[2,6-(iPr)(2)PhN=C(CH(3))]-6-[2,6-(iPr)(20PhN-C=CH(2)](C(5)H(3)N)}Fe(micro,eta(2)-N(2))Na (THF) (1) containing one N(2) unit terminally bound to Fe and side-on attached to the Na atom. In the process, one of the two imine methyl groups has been deprotonated, transforming the neutral ligand into the corresponding monoanionic version. When 4 equiv were employed, two other dinitrogen complexes {2-[2,6-(iPr)(2)PhN=C(CH(3))]-6-[2,6-(iPr)(2)PhN-C=CH(2)](C(5)H(3)N)}Fe(micro-N2)Na(Et(2)O)(3) (2) and {2,6-[2,6-(iPr)(2)PhN=C(CH(3))](2)(C(5)H(3)N)}Fe(micro-N(2))Na[Na(THF)(2)] (3) were obtained from the same reaction mixture. Complex 2 is chemically equivalent to 1, the different degree of solvation of the alkali cation being the factor apparently responsible for the sigma-bonding mode of ligation of the N(2) unit to Na, versus the pi-bonding mode featured in 1. In complex 3, the ligand remains neutral but a larger extent of reduction has been obtained, as indicated by the presence of two Na atoms in the structure. A further increase in the amount of reductant (12 equiv) afforded a mixture of {2-[2,6-(iPr)(2)PhN=C(CH(3))]-6-[2,6-(iPr)(2)PhN-C=CH(2)](C(5)H(3)N)}Fe-N(2) (4) and [{2,6-[2,6-(iPr)(2)PhN=C(CH(3))](2)(C(5)H(3)N)}Fe-N(2)](2)(micro-Na) [Na(THF)(2)](2) (5) which were isolated by fractional crystallization. Complex 4, also containing a terminally bonded N(2) unit and a deprotonated anionic ligand bearing no Na cations, appears to be the precursor of 1. The apparent contradiction that excess NaH is required for its successful isolation (4 is the least reduced complex of this series) is most likely explained by the formation of the partner product 5, which may tentatively be regarded as the result of aggregation between 1 and 3 (with the ligand system in its neutral form). Finally, reduction carried out in the presence of additional free ligand afforded {2,6-[2,6-(iPr)(2)PhN=C(CH(3))](2)(C(5)H(3)N)}Fe(eta(1)-N(2)){2,6-[2,6-(iPr)(2)PhN=C(CH(3))](20(NC(5)H(2))}[Na(THF)(2)] (6) and {2,6-[2,6-(iPr)(2)PhN=C(CH(3))](2)(C(5)H(3)N)}Fe{2,6-[2,6-(iPr)(2)PhN=C(CH(3))](2)(NC(5)H(2))}Na(THF)(2)) (7). In both species, the Fe metal is bonded to the pyridine ring para position of an additional (L)Na unit. Complex 6 chemically differs from 7 (the major component) only for the presence of an end-on coordinated N(2).     

Imido Complexes Derived from the Reactions of Niobium and Tantalum Pentachlorides with Primary Amines: Relevance to the Chemical Vapor Deposition of Metal Nitride Films

Reactions of niobium and tantalum pentachlorides with tert-butylamine (>/=6 equiv) in benzene afford the dimeric imido complexes [NbCl(2)(N(t)Bu)(NH(t)Bu)(NH(2)(t)Bu)](2) (90%) and [TaCl(2)(N(t)Bu)(NH(t)Bu)(NH(2)(t)Bu)](2) (79%). The niobium complex exists as two isomers in solution, while the tantalum complex is composed of three major isomers and at least two minor isomers. Analogous treatments with isopropylamine (>/=7 equiv) give the monomeric complexes NbCl(2)(N(i)Pr)(NH(i)Pr)(NH(2)(i)Pr)(2) (84%) and TaCl(2)(N(i)Pr)(NH(i)Pr)(NH(2)(i)Pr)(2) (84%). The monomeric complexes are unaffected by treatment with excess isopropylamine, while the dimeric complexes are cleaved to the monomers MCl(2)(N(t)Bu)(NH(t)Bu)(NH(2)(t)Bu)(2) upon addition of excess tert-butylamine in chloroform solution. Treatment of niobium and tantalum pentachlorides with 2,6-diisopropylaniline affords insoluble precipitates of [NH(3)(2,6-(CH(CH(3))(2))(2)C(6)H(3))](2)[NbCl(5)(N(2,6-(CH(CH(3))(2))(2)C(6)H(3)))] (100%) and [NH(3)(2,6-(CH(CH(3))(2))(2)C(6)H(3))](2)[TaCl(5)(N(2,6-(CH(CH(3))(2))(2)C(6)H(3)))] (100%), which react with 4-tert-butylpyridine to afford the soluble complexes [4-t-C(4)H(9)C(5)H(4)NH](2)[NbCl(5)(N(2,6-(CH(CH(3))(2))(2)C(6)H(3)))] (45%) and [4-t-C(4)H(9)C(5)H(4)NH](2)[TaCl(5)(N(2,6-(CH(CH(3))(2))(2)C(6)H(3)))] (44%). Sublimation of [NbCl(2)(N(t)Bu)(NH(t)Bu)(NH(2)(t)Bu)](2), MCl(2)(N(i)Pr)(NH(i)Pr)(NH(2)(i)Pr)(2), and [NH(3)(2,6-(CH(CH(3))(2))(2)C(6)H(3))](2)[MCl(5)(N(2,6-(CH(CH(3))(2))(2)C(6)H(3)))] leads to decomposition to give [MCl(3)(NR)(NH(2)R)](2) as sublimates (32-49%), leaving complexes of the proposed formulation MCl(NR)(2) as nonvolatile residues. By contrast, [TaCl(2)(N(t)Bu)(NH(t)Bu)(NH(2)(t)Bu)](2) sublimes without chemical reaction. Analysis of the organic products obtained from thermal decomposition of [NbCl(2)(N(t)Bu)(NH(t)Bu)(NH(2)(t)Bu)](2) showed isobutylene and tert-butylamine in a 2.2:1 ratio. Mass spectra of [NbCl(2)(N(t)Bu)(NH(t)Bu)(NH(2)(t)Bu)](2), [TaCl(2)(N(t)Bu)(NH(t)Bu)(NH(2)(t)Bu)](2), and [NbCl(3)(N(i)Pr)(NH(2)(i)Pr)](2) showed the presence of dimeric imido complexes, monomeric imido complexes, and nitrido complexes, implying that such species are important gas phase species in CVD processes utilizing these molecular precursors. The crystal structures of [4-t-C(4)H(9)C(5)H(4)NH](2)[NbCl(5)(N(2,6-(CH(CH(3))(2))(2)C(6)H(3)))], [NbCl(3)(N(i)Pr)(NH(2)(i)Pr)](2), [NbCl(3)(N(2,6-(CH(CH(3))(2))(2)C(6)H(3)))(NH(2)(2,6-(CH(CH(3))(2))(2)C(6)H(3)))](2), and [TaCl(3)(N(2,6-(CH(CH(3))(2))(2)C(6)H(3)))(NH(2)(2,6-(CH(CH(3))(2))(2)C(6)H(3)))](2) were determined. [4-t-C(4)H(9)C(5)H(4)NH](2)[NbCl(5)(N(2,6-(CH(CH(3))(2))(2)C(6)H(3)))] crystallizes in the space group P2(1)/c with a = 12.448(3) ?, b = 10.363(3) ?, c = 28.228(3) ?, beta = 94.92(1) degrees, V = 3628(5) ?(3), and Z = 4. [NbCl(3)(N(i)Pr)(NH(2)(i)Pr)](2) crystallizes in the space group P2(1)/c with a = 9.586(4) ?, b = 12.385(4) ?, c = 11.695(4) ?, beta = 112.89(2) degrees, V = 1279.0(6) ?(3), and Z = 2. [NbCl(3)(N(2,6-(CH(CH(3))(2))(2)C(6)H(3)))(NH(2)(2,6-(CH(CH(3))(2))(2)C(6)H(3)))](2) crystallizes in the space group P2(1)/n with a = 10.285(3) ?, b = 11.208(3) ?, c = 23.867(6) ?, beta = 97.53 degrees, V = 2727(1) ?(3), and Z = 2. [TaCl(3)(N(2,6-(CH(CH(3))(2))(2)C(6)H(3)))(NH(2)(2,6-(CH(CH(3))(2))(2)C(6)H(3)))](2) crystallizes in the space group P2(1)/n with a = 10.273(1) ?, b = 11.241(2) ?, c = 23.929(7) ?, beta = 97.69(2) degrees, V = 2695(2) ?(3), and Z = 2. These findings are discussed in the context of niobium and tantalum nitride film depositions from molecular precursors.