clipping process. Using threads 13a and 13b that contain two adipamide groups, more complicated systems have been investigated in which [2]rotaxane, [3]rotaxane, and free components are in equilibrium. Concentration- and temperature-dependent 1H NMR spectroscopic studies allowed the identification of all possible elements and the determination of their relative distributions in solution. For example
使用包含弱可逆OsVI-N配位键的双核大环化合物2,研究了[2]-和[3]轮烷的自组装和平衡动力学。当大环化合物2与线程4a-e混合在一起时,它们都包含一个己二酰胺位点,但端基的大小不同,[2]假轮烷和轮烷样复合物立即形成,其缔合常数> 7 x 103M(- 1)在298 K的CDCl3中。通过2D-EXSY实验研究的交换动力学表明,复合物的组装和拆卸是通过两个不同的途径(滑动或截短)发生的,这取决于端基的大小。滑动途径主要是产生假轮烷样复合物的较小端基,而剪切途径是产生轮状烷类复合物的较大端基。在相同条件下,交换势垒(deltaG ++)对于4a是14.3 kcalmol(-1),对于4d是16.7 kcalmol(-1),表明滑动过程比剪切过程至少快一个数量级。使用包含两个己二酰胺基团的线13a和13b,研究了更复杂的系统,其中[2]轮烷,[3]轮烷和游离组分处于平衡状态。浓度和温度相关的1H
Bis-diazeniumdiolates of Dialkyldiamines: Enhanced Nitric Oxide Loading of Parent Diamines
作者:Melissa M. Reynolds、Zhengrong Zhou、Bong K. Oh、Mark E. Meyerhoff
DOI:10.1021/ol050541z
日期:2005.7.1
[reaction: see text] The synthesis and characterization of a series of symmetric bis-dialkyldiamine-based diazeniumdiolates, RN[N(O)NO(-)Na(+)](CH(2))(x)()N[N(O)NO(-)Na(+)]R', are reported. Preparation of corresponding intramolecular diazeniumdiolates of the form RN[N(O)NO](-)(CH(2))(x)()NH(2)(+)R' with alkyl groups > (CH(2))(4)CH(3) have been shown previously to lack stability. In contrast, sodium-stabilized
tetralactam macrocyle based on two symmetric components: a Rh(III) bis-porphyrin and a bis-pyridyl ligand. We probe the binding properties of the tetralactam macrocycle with adipamide derivatives using 1H NMR spectroscopy. On the one hand, we show that the binding of the adipamide having linear alkyl chains that can thread through the intact macrocycle's cavity produces a weakly bound 1 : 1 complex stabilized
我们报道了基于两个对称组分的稳健双核四内酰胺大环的自组装:Rh( III )双卟啉和双吡啶基配体。我们使用1来探究四内酰胺大环化合物与己二酰胺衍生物的结合特性核磁共振氢谱。一方面,我们表明,具有可以穿过完整大环空腔的线性烷基链的己二酰胺的结合产生了由四个分子间氢键稳定的弱结合的1:1复合物,并且具有[2]拟轮烷的优选结合几何形状拓扑。另一方面,我们检测到在具有笨重塞子(哑铃轴)的类似己二酰胺的结合中形成了两种不同的复合物。哑铃客体的初始添加诱导形成 1:1 复合物,该复合物具有1 H 化学位移时间尺度上的快速交换动力学和exo-循环(非螺纹)结合几何形状。值得注意的是,在存在大量过量的哑铃客体和适当浓度的大环化合物(> 5 mM)的情况下,我们观察到第二种物种的出现,表现出缓慢的交换动力学。这一观察结果使得[2]轮烷拓扑无可争议地分配给第二个复合物。与之前描述的双核 Zn(II) 对应物相比,双核Rh
Polyphenylene ether compositions having improved processability
申请人:MITSUBISHI PETROCHEMICAL CO., LTD.
公开号:EP0115218A2
公开(公告)日:1984-08-08
A polyphenylene ether composition comprises polyphenylene ether, optionally styrene resin, and a diamide represented by the formula
wherein R' is a C1-10 linear or branched saturated or unsaturated aliphatic hydrocarbon residue, an alicyclic hydrocarbon residue, an aromatic hydrocarbon residue, or such a residue having one or more substituents; and R2 and R3, which may be the same of different, are each a C1-10 linear or branched saturated or unsaturated aliphatic hydrocarbon residue, an alicyclic hydrocarbon residue or an aromatic hydrocarbon residue, or such a residue having one or more substituents.
The composition has improved processability, due to high flowability, with a minimum decrease in heat resistance.