六元瓜环与二氯化-1,8-二(2-苯并咪唑基)辛烷的自组装模式

采用¹H NMR、 荧光光谱和紫外吸收光谱法考察了主体六元瓜环与合成客体二氯化-1,8-二(2-苯并咪唑基)辛烷的自组装模式. 结果表明, 六元瓜环能与二氯化-1,8-二(2-苯并咪唑基)辛烷发生相互作用, 瓜环包结客体分子的苯并咪唑基团, 烷基链置于瓜环端口外侧. 自组装模式与主客体的摩尔比密切相关. 当主客体的摩尔比为1:1时, 1个瓜环包结客体分子的一端苯并咪唑基团形成棒槌形的包结配合物; 当主客体的摩尔比为2:1时, 2个瓜环分别包结客体分子的两端苯并咪唑基团形成哑铃型的主客体包结配合物.     

八元瓜环与1,7-二(2-苯并咪唑)-庚烷的超分子自组装

以氯化1,7-二（2-苯并咪唑）-庚烷（SBHt）为客体,八元瓜环（Q[8]）为主体,利用¹H NMR技术、动态光散射实验、荧光发射光谱、紫外吸收光谱详细探索了其在溶液中的相互作用、超分子自组装过程及作用模式. 首先考察了八元瓜环对客体pKa的影响,确定了研究主客体相互作用的条件,并详细探索了主客体的超分子自组装过程及作用模式. 主体Q[8]与客体SBHt相互作用的¹H NMR谱图表明,主客体相互作用自组装形成1：1超分子聚合物. 这一推断得到动态光散射实验、紫外吸收光谱、荧光发射光谱测定结果的证实,并通过紫外吸收光谱、荧光发射光谱确定其表观稳定常数分别为2.79×10⁵ L/mol及2.48×10⁵ L/mol. 而晶体结构测定表明主体Q[8]与客体SBHt自组装形成1：2的简单包结配合物. 导致Q[8]与SBHt在溶液中和固体状态下形成不同自组装结构可能源于瓜环的外壁作用与包结作用竞争所致.     

七、八元瓜环与二溴化1,n-亚烷基-二-2-甲基吡啶的超分子自组装

合成和表征了4个碳链长度不同二溴化1,n-亚烷基-二-2-甲基吡啶(客体,n=6,8,10,12),利用1H NMR技术、热重分析及紫外吸收光谱法考察了这些客体与七、八元瓜环(主体)的相互作用,以及形成的主客体包结物的结构特征.研究结果表明4个客体与七、八元瓜环形成不同的主客体包合物.七元瓜环可穿梭在线性客体分子上形成类轮烷型或哑铃型主客体包合物;而由于具有较大的空腔,八元瓜环可包容弯曲状的整个客体分子.     

瓜环与含羟基功能基二胺包结配合物的晶体结构及相互作用的研究

合成并表征了含羟基功能基的二胺1,3-二(2-氨基苯氧基)-2-丙醇(客体). 利用X射线衍射方法研究了客体与八元瓜环Q[8]所形成包结配合物的晶体结构. 结果表明主客体间形成了1∶2的包结配合物, 两个客体分子分别从瓜环的两个端口进入瓜环内腔, 在腔内两个客体分子中的苯环间存在着π-π相互作用. 利用1H NMR技术及紫外-可见吸收光谱对主客体间的相互作用进行考察, 所得结果与晶体结构吻合.     

六元瓜环与含双苯并咪唑功能基烷烃的自组装模式及晶体结构

以含有双苯并咪唑功能基的烷烃化合物二氯化-1,4-二(2,2’-苯并咪唑基)丁烷(SBB)为客体,普通六元瓜环(Q[6])为主体,利用1H NMR技术、荧光发射光谱和X-单晶衍射实验等考察了主客体的自组装模式.1 H NMR技术结果显示,当主客体的比例为1:1时,在水溶液中,1个Q[6]包结1个客体分子的一端苯并咪唑基团;在结晶固态条件下,X-单晶衍射实验测试结果是Q[6]包结客体分子的烷基链.荧光发射光谱表明,当主客体比例为2:1时,2个Q[6]分别包结1个客体分子的两端苯并咪唑基团形成哑铃型的实体配合物。     

八元瓜环对1,ω-二(2-氨基吡啶)烷烃光致环加成反应的超分子催化性能的研究

合成了三种不同链长的1,ω-二(2-氨基吡啶)烷烃,分别为二溴化1,4-二(2-氨基吡啶)丁烷(C4)、二溴化1,6-二(2-氨基吡啶)己烷(C6)、二溴化1,8-二(2-氨基吡啶)辛烷(C8).考察了八元瓜环(Q[8])与上述三种1,ω-二取代烷烃的主客体相互作用,运用1H NMR及UV-vis证明三种客体与Q[8]的作用模式均不相同.在此基础上,考察了八元瓜环对三种底物光致环加成反应的超分子催化性能.结果表明,由于三种底物与Q[8]的主客体作用模式不同,八元瓜环对它们光二聚反应的超分子催化性能也各有差异.     

七元瓜环与1,7-二(2-苯并咪唑)庚烷的相互作用及自组装

利用~1H NMR法、紫外吸收光谱法、荧光发射光谱法和单晶X射线衍射等方法考察了七元瓜环(Q[7])与氯化1,7-二(2-苯并咪唑)庚烷(SBHt)在酸性溶液中的相互作用过程及组装模式.首先考察了主客体相互作用对客体p Ka的影响,以确定研究主客体相互作用以及组装过程的实验条件.~1H NMR滴定实验结果表明,在水溶液中主客体可形成1∶1和2∶1的主客体包结配合物,当主客体物质的量之比为1∶1时,Q[7]包结SBHt的烷基链,两端苯并咪唑基团处于瓜环端口外侧;当主客体物质的量之比为2∶1时,两个Q[7]分别包结同一SBHt分子的两端苯并咪唑基团,这一实验结果得到荧光发射光谱的佐证.Q[7]与SBHt形成1∶1的主客体包结配合物的晶体结构表明,客体烷基链在瓜环空腔内发生折叠以使其通过离子偶极及氢键与Q[7]有效作用.     

两种部分甲基取代瓜环配合物的晶体结构(英文)

本文报道了2种新的部分甲基取代瓜环配合物的晶体结构,利用X-射线单晶衍射技术表征了2种配合物的结构,在CdCl2溶液中,1,2,4,5-八甲基六元瓜环选择性的包结客体分子1,2-(2,2′-bisbenzimidazolyl)ethanedichloride,形成2∶1的哑铃型主客体包结配合物;而1,2,4-六甲基五元瓜环(HMeQ[5])与钠离子配位形成包结一个水分子的"分子胶囊","分子胶囊"之间通过氢键自组装形成一维的超分子长链。     

瓜环与喹啉衍生物包结配合行为研究

利用¹H NMR以及荧光技术研究了六、七、八元瓜环与2-苯基喹啉、N-正丙基溴化异喹啉、3-氨基喹啉及7,8-苯并喹啉的相互作用.两种方法的考察结果均表明,2-苯基喹啉能与这3种瓜环发生相互作用,其中六、七元瓜环与2-苯基喹啉形成1∶1的稳定包结配合物,包结常数分别为1.6×10⁴和3.2×10³L/mol.八元瓜环能与2-苯基喹啉形成1∶2包结物.¹H NMR结果还表明,3种瓜环均能与N-正丙基溴化异喹啉相互作用,其化学计量比均为1∶2;七元瓜环与7,8-苯并喹啉相互作用,化学计量比约为1∶1.荧光法也表明八元瓜环能与N-正丙基溴化异喹啉、3-氨基喹啉及7,8-苯并喹啉发生相互作用,并且荧光强度随瓜环浓度增加而下降,其化学计量比为1∶2.同时,讨论了上述主客体包结配合物的作用模式.     

对称四甲基六元瓜环与1-丁基-4,4’-联吡啶的超分子自组装

设计合成了客体分子1-丁基-4,4’-联吡啶溴化物(BV+),利用核磁共振、紫外-可见吸收光谱、热重分析及X射线单晶衍射研究其与对称四甲基六元瓜环(TMeQ[6])的超分子自组装及形成的主客体包结配合物的结构特征.结果表明,在溶液中及固体状态下,TMeQ[6]均包结BV+的烷基链部分形成1∶1包结配合物.     

Host–guest complexes of various cucurbit[n]urils with the hydrochloride salt of 2,4-diaminoazobenzene

The interaction products of normal cucurbit[n]urils (n = 7, 8; Q[7] Q[8]) and a sym- tetramethyl-substituted cucurbit[6]uril derivative (TMeQ[6]) with the hydrochloride salts of 2,4-diaminoazobenzene (g·HCl) were investigated in aqueous solution using ¹H NMR spectroscopy, electronic absorption spectroscopy, as well as single crystal X-ray diffraction. The ¹H NMR spectra analysis established a basic interaction model in which inclusion complexes with a host:guest ratio of 1:1 form for the TMeQ[6] and Q[7] cases, while they form with a host:guest ratio of 1:2 for the Q[8] case. Commonly, the hosts selectively bound to the phenyl moieties of the guests. Absorption spectrophotometric analysis in aqueous solution defined the stability of the host–guest inclusion complexes at pH 3.2. Quantitatively, at this pH, complexes with a host:guest ratio of 1:1—those with smaller hosts TMeQ[6] and Q[7]—formed with logK values between 6 and 7. That with host Q[8] and a host:guest ratio of 1:2 formed with a logK value of 10.8. Single crystal X-ray structures of the inclusion complexes TMeQ[6]–g·HCl and Q[8]–g·HCl showed the phenyl moiety of the guest inserted into the host cavity. This result supports the solution-based ¹H NMR spectroscopic study.     

Host–guest complexes of some cucurbit[n]urils with the hydrochloride salts of some imidazole derivatives

Interaction between the normal cucurbit[n]urils (n = 6,7,8; Q[6], Q[7], Q[8]) and a sym-tetramethyl-substituted cucurbit[6]uril derivative (TMeQ[6]) with the hydrochloride salts of some imidazole derivatives N-(4-hydroxylphenyl)imidazole (g1), N-(4-aminophenyl)imidazole (g2), 2-phenylimidazole (g3) in aqueous solution was investigated by using ¹H NMR spectroscopy, electronic absorption spectroscopy and fluorescence spectroscopy, as well as by using a single crystal X-ray diffraction determination. The ¹H NMR spectra analysis established a basic interaction model in which inclusion complexes with a host:guest ratio of 1:1 forms for the Q[6]s and Q[7] cases, while with a host:guest ratio of 1:2 form for the Q[8] cases. It was common that the hosts selectively bound the phenyl moiety of the guests. Absorption spectrophotometric and fluorescence spectroscopic analysis in aqueous solution defined the stability of the host–guest inclusion complexes at pH 5.8 with a host:guest ratio of 1:1 form quantitatively as logK values between 4 and 5 for the smaller hosts Q[6 or 7]s, while with a host:guest ratio of 1:2 form quantitatively as logK values between 11 and 12 for the host Q[8]. Two single crystal X-ray structures of the inclusion complexes TMeQ[6]-g2 · HCl and TMeQ[6]-g3 · HCl showed the phenyl moiety of these two guests inserted into the host cavity, which supported particularly the ¹H NMR spectroscopic study in solution.     

水溶性六元瓜环衍生物与1,ω-亚烷基吡啶主客体配合物的^1HNMR及晶体结构

利用^1HNMR技术以及单晶X衍射技术考察对称四甲基取代六元瓜环（TMeQ[6]）与几种1,ω-亚烷基吡啶阳离子（ω=2,4,6,8,10）客体的相互作用．在这些包结配合物中,TMeQ[6]的端口效应以及空腔效应同时存在,其主客体作用模式随着客体亚烷基碳链长短不一而各不相同．对于客体1,2-二乙基吡啶（Edpy）,TMeQ[6]包结Edpy的带正电荷的吡啶环部分,形成一不对称的包结配合物;对于客体1,4-二丁基吡啶（Bdpy）,TMeQ[6]选择性包结Bdpy的吡啶环部分或烷基部分存在竞争作用和快速交换;而具有较长碳链的客体1,6-二己基吡啶（Hdpy）和1,8-二丁庚基吡啶（Odpy）与TMeQ[6]通过空腔的疏水作用以及外部的离子-偶极作用形成稳定的类轮烷包结配合物;客体1,10-二癸基吡啶（Ddpy）的两个吡啶环分别被两个TMeQ[6]包结形成哑铃型的包结配合物．     

七元瓜环与N,N’-二烷基-1,3-(4,4’-二吡啶基)丙烷衍生物的相互作用

以1,3-(4,4’-二吡啶基)丙烷为母体, 合成了N,N’-二乙基、二丁基、二己基以及二辛基1,3-(4,4’-二吡啶基)丙烷衍生物. 利用1H NMR技术和紫外吸收光谱法, 考察了Q[7]与上述链状吡啶衍生物的相互作用. 实验结果表明, Q[7]与客体PC0, PC2作用, 瓜环包结客体的二吡啶基丙烷部分形成1∶1的包结配合物; 对于取代烷基碳链数大于4的N,N’-二烷基-1,3-(4,4’-二吡啶基)丙烷衍生物, 随着主体与客体摩尔比值的增加, 体系中主-客体相互作用的主导模式是Q[7]逐渐包结了客体二吡啶基丙烷部分, 进而形成Q[7]包结客体两端取代烷基, 甚至形成一个客体分子上“挂满”3个主体瓜环的包结物.     

七元瓜环与N,N′-二烷基-1,3-(4,4′-二吡啶基)丙烷衍生物的相互作用

以1,3-(4,4′-二吡啶基)丙烷为母体,合成了N,N′-二乙基\,二丁基\,二己基以及二辛基1,3-(4,4′-二吡啶基)丙烷衍生物.利用 1H NMR技术和紫外吸收光谱法,考察了Q[7]与上述链状吡啶衍生物的相互作用.实验结果表明,Q[7]与客体PC0,PC2作用,瓜环包结客体的二吡啶基丙烷部分形成1∶1的包结配合物;对于取代烷基碳链数大于4的N,N′-二烷基-1,3-(4,4′-二吡啶基)丙烷衍生物,随着主体与客体摩尔比值的增加,体系中主-客体相互作用的主导模式是Q[7]逐渐包结了客体二吡啶基丙烷部分,进而形成Q[7]包结客体两端取代烷基,甚至形成一个客体分子上"挂满"3个主体瓜环的包结物.     

Host-guest complexes of a water soluble cucurbit[6]uril derivative with some dications of 1,ω-alkyldipyridines: <Superscript>1</Superscript>H NMR and X-ray structures

Interactions between a symmetrical tetramethyl-substituted cucurbit[6]uril (host: TMeQ[6]) and 1,ω-alkylenedipyridine (ω = 2, 4, 6, 8, 10) dicationic guests were investigated using ¹H NMR spectroscopy and single crystal X-ray crystallography. In these inclusion complexes, combined cavity and portal binding in TMeQ[6] were observed, and the length of the bridged alkylene was found to play an important role not only in balancing the overall hydrophilic/hydrophobic interaction between the host and the guest, but also in defining the structure of the resulting inclusion complexes. For the guest 1,2-ethylenedipyridine (Edpy), TMeQ[6] includes a positively charged pyridine ring of Edpy to form an unsymmetrical inclusion complex; for the guest 1,4-butylenedipyridine (Bdpy), TMeQ[6] includes a positively charged pyridine ring of Bdpy, but the different competitive interactions in and between the related inclusion complexes could lead to a fast exchange between the hosts and guests. For the guests with longer bridge chains, such as 1,6-hexamethylenedipyridine (Hdpy) or 1,8-octylenedipyridine (Odpy), a stable pseudorotaxane inclusion complex is formed by combining the hydrophobic cavity and the outer portal dipole-ion interactions. However, for 1,10-decatylenedipyridine (Ddpy), the two TMeQ[6] host molecules include the two end pyridine rings of Ddpy and form a dumbbell inclusion complex. Supported by the National Natural Science Foundation of China (Grant Nos. 20662003 & 20767001), the International Collaborative Project of Guizhou Province (Grant No. 2007400108), the Science Technology Fund of Guizhou Province (Grant No. J-2008-2012) and the Natural Science Youth Foundation of Guizhou University (Grant No. 2007-005)     

A three dimensional framework induced by �������� stacking of 2,2��-(Alkylene-1,6-diyl)diisoquinolinium from Q[6]-based Pseudorotaxane

A bromide salt of 2,2??-(hexane-1,6-diyl) diisoquinolinium (K6) was designed, synthesized and introduced to construct a novel framework induced by ??···?? stacking of 2,2??-(alkylene-1,??-diyl)diisoquinolinium from Q[6]-based pseudo-rotaxanes. The crystal structure of the compound revealed that the assembled framework based on the Q[6]-2,2??-(alkylene-1,6-diyl)diisoquinolinium pseudo-rotaxanes have stoichiometries of {(K6)@(Q[6])}²⁺·2Br^?·7(H₂O). The compound 1 has a novel three-dimensional framework constructed of two different channels?Done containing stacked isoquinolyl moieties from the K6@Q[6] pseudorotaxanes and the other containing the bromide anions. ¹H NMR spectra analysis was performed and confirmed the pseudorotaxane interaction model in which the 2,2??-(alkylene-1,6-diyl)diisoquinolinium guest threads into the cavity of Q[6] with the alkyl chain included inside the cavity and the two end isoquinolyl moieties protruding from the two opening portals. Absorption spectrophotometric and fluorescence spectroscopic analyses of the host?Cguest inclusion complex in aqueous solution found that the complexes were most stable at a host:guest mole ratio of 1:1. At this ratio, the complex has binding constants (K) ~10⁶.     

七、八元瓜环对萘二胺异构体相互作用的考察

利用紫外吸收光谱、荧光光谱以及¹H NMR方法考察了七、八元瓜环(Q[7], Q[8])与1,8-萘二胺(g1), 2,3-萘二胺(g2), 1,5-萘二胺(g3)的相互作用. 实验结果表明: Q[7]与客体g1发生端口作用, 作用比为1∶1; Q[7]与客体g2, g3相互作用也形成1∶1的包结配合物. Q[8]与三种客体相互作用情况各不相同, 除Q[8]与客体g2相互作用形成1∶2的包结配合物; Q[8]与客体g1或g3可发生相互作用, 形成溶解性较差的作用产物, 其表观相互作用的比例为1∶1. 考察溶液酸度对主客体相互作用的影响还表明: 当pH大于某一值之后, 如Q[7]主客体体系, pH大于6.0; Q[8]主客体体系, pH大于12.0, 用光谱方法观察不到瓜环与客体的相互作用. Q[7], Q[8]为主体的上述主客体作用产物分别与金刚烷胺盐酸盐、1,10-癸二胺盐酸盐的竞争反应结果表明, 已作用的萘二胺异构体容易被所选用的竞争客体所取代, 只有g2与Q[8]形成的包结配合物被1,10-癸二胺盐酸盐部分取代.