Facile one-step synthesis of a thia-bridged bis-1,10-phenanthroline macrocycle

An efficient one-pot synthesis of a macrocyclic ligand, consisting of two 1,10-phenanthroline nuclei bridged by sulfur, is described. A spectrophotometric investigation reveals the isolated compound to be the mono-trifluoroacetate salt. Symmetrical NH- and S-bridged tetradentate ligands were also synthesized by the new method.     

Synthesis and simple separation of β-pyrrole sulfonated porphycenes

New water-soluble porphycenes having sulfonic acid groups at the β-pyrrolic positions were synthesized and characterized by UV-vis, NMR, IR, and mass spectroscopy as well as elemental analyses. The series of mono- to tri-sulfonato derivatives were simply separated by the extraction method.     

Synthesis of a new and versatile macrocyclic NADH model

A new macrocyclic NADH model 1 has been designed and synthesised. The new model consists of the same subunits as previously reported models. However, the present model is designed as such that the pyridine nitrogen of the nicotinamide units are not incorporated in the macrocyclic framework. Thus, properties such as solubility can easily be varied by alkylation with an appropriate agent. The macrocyclic framework was prepared in 7 steps. Methylation of the pyridine nitrogens followed by reduction gave the desired model. This model compound was found to reduce methyl benzoylformate stereoselectively in good yield with 48% enantiomeric excess.     

Preliminary study on dual fluorescence behavior of porphyrin

It is well known that porphyrin derivatives play a key role in the primary process of photo-synthesis[1], in which porphyrins directly absorb the sunlight or indirectly acquire excitation en-ergy from light-harvesting antenna system to reach their excited state, and then donate electrons to quinone acceptors to yield a series of charge-separated species. In general, only first singlet ex-cited state of porphyrins is involved in energy transfer process[2]. However, highly excited state (S2 stat…     

Synthesis of novel rigid triazine-based calix[6]arenes

In this report, the stepwise synthesis of a novel rigid and functionalised macrocycle 2 based on triazine and phenylenediamine linkers, is presented. Poor recognition of the macrocycle 2 for its substrates is observed, which shows experimentally that for the meltriazine based-calix[6]arene system, the binding ability of the melamine moiety gets more benefit from the ring flexibility derived from a xylenediamine linker 1 than from a phenylenediamine linker 2.     

Macrocycle opening in crown ethers

Macrocycle opening in derivatives of benzocrown ethers under the action of amines is affected by the nature of the heteroatoms in the macrocycle, the nature of the functional group in the benzene ring of the crown ether, and the length, branching, and number of hydrocarbon radicals at the amine nitrogen atom. A distinguishing feature of this reaction is the template effect of MeNH₃ ⁺, Me₂NH₂ ⁺, Na⁺, and K⁺ ions.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 687–692, March, 1996.For Part I see Ref. 1.     

Macrocycle opening in formyl derivatives of benzocrown ethers under the action of methylamine

A new method for synthesizing nitrogen-containing podands by nucleophilic regioselective cleavage of the macrocycle in formyl derivatives of benzocrown ethers by heating with methylamine and methylammonium chloride has been developed. This reaction is the first example of crown ether opening by a nitrogen-containing nucleophile.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 950–953, May, 1995.     

碱金属沸石上乙醇双分子缩合反应及其机理

首次发现在碱金属Ｘ沸石上乙醇能够发生以正丁醇为主产物的双分子缩合反应，在所研究的催化剂中，含Ｒｂ的ＬｉＸ沸石表现出较高的反应活性和选择性。反应机理的研究表明，反应不经过ａｌｄｏｌ缩合步骤。在此基础上，对反应机理提出了新建议：在碱性沸石作用下，乙醇的β－位Ｃ－Ｈ键被活化，双分子脱水导致缩合。碳链的增长按此模式进行。     

西佛碱大环双核钴（Ⅱ）配合物的合成,光谱及磁性

本文以２．６─二乙酰吡啶和１，３一二氨基一２一丙醇通过模板合成西佛碱大环配体Ｈ＿２Ｌ（图１），并合成了它的Ｃｏ（Ⅱ）、Ｎｉ（Ⅱ）及Ｆｅ（Ⅱ）的双核配合物，重点讨论了Ｃｏ＿２（ＨＬ）（ＣｌＯ＿４）＿２（ＮＯ＿３）·４Ｈ＿２Ｏ配合物的光谱与磁性。变温磁化率数据（４─３００Ｋ）通过用最小二乘法与理论方程拟合，得到磁参数为Ｊ＝－１．２４ｃｍ￣（－１），θ＝－０．２４Ｋ，表明配合物中ｃｏ（Ⅱ）－Ｃｏ（Ⅱ）间存在弱的反铁磁相互作用，分子间也存在反铁磁相互作用。     

Solid state photoreactions occurring at the interface between crystallites of two different organic compounds

This paper deals with the solid state bimolecular photoreactions occurring at the interface between crystallites of two different organic compounds prepared as a polycrystalline mixture by melting-resolidification. The photoreactions include the photoaddition of NH compounds to aromatic and olefinic double bonds, hydrogen abstraction, condensation reaction via photoelectron transfer and [2+2] photoaddition. Particular attention is focused on the characterization of the polycrystalline mixture, the selectivity of the photoreactions in the solid state compared with those in the solution phase and the factors controlling the photoreactions.