Reaction of barbituric/thiobarbituric acid with phosphines or phosphites and dialkyl acetylenedicarboxylates for synthesis of phosphorus zwitterions or phosphonate derivatives

Abstract

A three-component reaction between barbituric/thiobarbituric acid, phosphines, and dialkyl acetylenedicarboxylates in dry acetonitrile led to the formation of barbiturate/thiobarbiturate-functionalized stable zwitterionic salts in a one-pot process. When trialkyl phosphites were used instead of phosphines, barbiturate/thiobarbiturate-functionalized phosphonates were obtained in good yields.     

新型sPS/PET/SsPS-Zn工程塑料合金的研究

熔融共混法制备了新型综合性能较好的间规聚苯乙烯 (sPS) 聚对苯二甲酸乙二醇酯 (PET) 磺化间规聚苯乙烯锌盐 (SsPS Zn)工程塑料合金 ,研究了合金结构与性能之间的关系 .加入SsPS Zn后 ,合金的力学性能先提高而后下降 ,当sPS PET SsPS Zn为 85 15 2 (质量比 )时 ,合金的综合力学性能较好 ,冲击强度达到 10 6kJ m2 ,为纯sPS的 2 5倍 ;加入SsPS Zn后 ,合金的耐热性提高 ;合金中sPS的熔点与纯sPS相同 ,而初始结晶温度和达到最大结晶速度时的温度均高于纯sPS ,且基本不受SsPS Zn用量的影响 .PET的熔点、初始结晶温度、达到最大结晶速率时的温度和结晶度均随SsPS Zn用量的增加而逐渐降低 ;DMA结果中所有合金均只呈现一个Tg,并且加入SsPS Zn后 ,Tg 和半峰宽都逐渐提高 ,常温下的储能模量在其用量为 2份时达到最大值 ;SEM观察到加入 2份SsPS Zn后 ,PET分散相的尺寸明显减小 ,继续增加其用量 ,PET分散相的尺寸反而有所增大和不均匀 ,并且合金的冲击断面由显著的层状结构转为相对平整     

La和Nd在其氯化物熔体中的电化学腐蚀

稀土金属在其氯化物熔盐中的自腐蚀是导致电解制备稀土金属时电流效率降低的一个重要原因。但由于实验技术上的困难,有关这方面的研究报道不多。本文将在水溶液体系中常用的电化学弱极化测量腐蚀速度及电化学参数的方法用之于La、Nd在其氯化物熔盐体系中的腐蚀,表明同样适用。     

探析镁与碱性盐溶液反应的复杂性与可行性——以镁与碳酸钠溶液反应为例

一次验证镁与NaHCO3溶液反应得到H2的实验中，发现镁能与饱和Na2CO3溶液作用持续释出H2，为此通过分析Mg/H2O体系的热力学数据和研究其动力学机理认为实现镁与水溶液作用能持续释出H2的有效方法：在溶液中加入能破坏氢氧化镁保护层的某些离子。并设计有关实验证明：在碱性溶液中，若加入能与Mg2+形成稳定配合物的其他阴离子（如甘氨酸根离子、草酸根离子、EDTA等），则镁就能与碱性的盐溶液持续反应。     

4-甲氧基-N-(2-N′, N′-二甲基氨基乙基)萘二甲酰亚胺烯丙基氯化铵的合成与光学性质

4-甲氧基-N-(2-N′; N′-二甲基氨基乙基)萘二甲酰亚胺烯丙基氯化铵的合成与光学性质;荧光单体;季铵盐;合成;萘酐     

Synthesis and Crystal Structure of an Infinite 1D Zigzag Chain Compound (dimbH~+)(ClO_4~-) and Its Comparison with (dimb)2H_2O (dimb = 1,3-Di(imidazol-1-ylmethyl)-5-methylbenzene)

1 INTRODUCTION Recently the rational design and preparation of novel functional materials are one of the highlights in supramolecular chemistry and crystal engi- neering[1]. How to control the molecular structures and topology in the process of self-assembly has attracted extensively attention[2]. To date, a lot of complexes containing well-designed bidentate[3～6], tripodal[7, 8] and hexadentate[9] imidazole moiety ligands have been synthesized by chemists. Some of them have interestin…     

Preparation and antibacterial activity of hybrid materials containing quaternary ammonium salts via sol-gel process

Organic-inorganic hybrid coatings containing quaternary ammonium salts (QAS) bonded to the organic-inorganic network were prepared from tetraethoxysilane and triethoxysilane terminated poly(ethylene glycol)-block-poly(ethylene) using a sol-gel process. They were applied as a thin layer (0.6-1 μm) to PE films and the antibacterial activity of the coated films was tested against both Gram-negative (Escherichia coli ATCC 25922) and Gram-positive (Staphylococcus aureus ATCC 6538) bacteria. Measurements at different contact times showed a rapid decrease of the viable count for both the tested strains. In particular, after 48 h of contact, a decrease of 96.4% and 99.1% of E. coli and S. aureus, respectively, was observed. The permanence of the antibacterial activity of the coated films was demonstrated through repeated washings and prolonged immersion in physiological saline solutions at 37 °C. Indeed, due to the removal of QAS moieties by the nucleophilic attack of water, the antibacterial activity after 24 h was strongly reduced when measured on samples submitted to several washings. However, a quite good antibacterial activity was observed even on the same samples after 96 h, probably due to a spontaneous partial restoring of the QAS on the surface. Very good transparency, quite good adhesion and high wettability are further features of these hybrid coatings.     

New reaction of the sodium salt of 2-nitroethanol. X-ray analysis of the sodium salt of 2-oxo-3-hydroxypropionic acid oxime, 2-bromo-2-nitropropane-1,3-diol,and the model 2,2-dinitropropane-1,3-diol

A novel reaction of the sodium salt of 2-nitroethanol in aqueous ammonia resulted in the sodium salt of 2-oxo-3-hydroxypropionic acid oxime (1) has been found. Bromination of1 affords 2-bromo-2-nitropropane-1,3-diol (2) with a previously unknown molecular conformation. The formation mechanisms of compounds1 and2 were suggested. X-ray analysis of products1,2 and that of the model compound, 2,2-dinitropropane-1,3-diol, was performed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1217–1221, May, 1996.     

Binary and ternary complexes of copper(II) with some dihydroxycoumarins

The complexation behaviour of copper(II) with a series of selected dihydroxycoumarins has been studied. Copper(II) binary complexes with esculetin, daphnetin and their 4-methyl and 4-phenyl derivatives and ternary complexes having a secondary ligand, ammonia or pyridine have bean synthesized. The general composition of binary complexes has bean found to be [Cu (H₂O)₂ (HL)₂] and that of ternary complexes as [Cu (L) (X)₄] (where X = NH₃ or C₅H₅N). The magnetic studies indicate all the complexes to be monomeric in nature. IR studies show that one of the two phenolic hydroxyl groups present in the ligand is lost during complexation. It is concluded that of the four ligands attached to the copper atom dihydroxycoumarin is bound most firmly.     

盐湖卤水提锂分离材料的研究进展

采用吸附或离子交换技术直接从中低锂含量盐湖卤水中提取锂是最经济、最理想的提锂技术路线,寻找、研究性能优异的锂的吸附分离材料,是实现这一技术路径的关键。重点阐述了离子交换与吸附法提锂的各种分离材料,并指出了盐湖卤水提锂今后的研究方向。