Novel Bis(bibenzyl) and (Propylphenyl)bibenzyl Derivatives from Dendrobium nobile

Two novel compounds possessing a bis(bibenzyl) (see 1 ) and a (propylphenyl)bibenzyl skeleton (see 2 ) and eight known compounds were isolated from the stems of Dendrobium nobile Lindl . (Orchidaceae). Their structures were identified by spectroscopic analyses.     

双(取代苯酰氧基)二茂钛衍生物的质谱分析

二茂钛类衍生物具有催化抗肿瘤活性,因而引起人们的研究兴趣。我们曾探讨了一系列双(取代苯酰氧基)二茂钛衍生物、含茂钛聚合物的合成、光谱、质谱及其反应性。本文报道有关衍生物的质谱分析,并讨论其规律性。     

Bis(trimethylsilyl)diimine: Preparation,Structure, and Reactivity

The highly reactive compound bis(trimethylsilyl)diimine (BSD), which was first prepared by oxidation of lithium tris(trimethylsilyl)hydrazide, is light blue, sensitive to thermolysis and hydrolysis, and ignites spontaneously in air. On the basis of electron transfer, acid-base, or free-radical reactions, it acts in particular as a (preparatively useful) redox system and as an agent for the introduction of azo groups. Redox reactions lead by oxidation or reduction of the other reactant through two oxidation stages to hydrazine derivatives or molecular nitrogen, and in the case of electrochemical reduction, to BSD radical-anions. Azo-group transfers, on the other hand, yield new inorganic azo compounds with no change in the oxidation state of the diimine group.     

双苯并咪唑衍生物对N80钢的缓蚀效果

选用1,3-双(2-苯并咪唑基)丙烷(BBP),1,3-双(2-苯并咪唑基)-2-氧杂丙烷(DMDB),N,N-双(2-苯并咪唑亚甲基)胺(IDB),1,3-双(2-苯并咪唑基)-2-硫代丙烷(BBMS)4种结构相似的双苯并咪唑衍生物作为N80油管钢缓蚀剂。采用失重法和电化学极化测试分别考察了不同缓蚀剂的缓蚀性能及其与KI复配后在pH=4.5的饱和CO2溶液中对N80钢的缓蚀效果。结果表明,此系列双苯并咪唑衍生物在投加量较小的情况下即对N80钢均具有较好的缓蚀效果,且此系列缓蚀剂既抑制了阳极过程,又抑制了阴极过程,为混合型缓蚀剂。当1,3-双(2-苯并咪唑基)-2-硫代丙烷(BBMS)与KI复配后,缓蚀机理没有发生改变,且缓蚀率明显提高,其浓度均为2mmol/L时,缓蚀率高达95.09%。     

Spirophosphoranes and Polycyclic Hexacoordinated Phosphorus Derivatives in the Phosphorylation Reactions of Bis(O-Hydroxyaryl)Diimines

Abstract

A new approach to the synthesis of spirophosphoranes was developed. It is based on the reaction of hexamethyltriamidophosphite with bis(o-hydroxyaryl)diimines.     

Bis(dicarbollide) Complexes of Transition Metals as a Platform for Molecular Switches. Study of Complexation of 8,8′-Bis(methylsulfanyl) Derivatives of Cobalt and Iron Bis(dicarbollides)

Complexation of the 8,8′-bis(methylsulfanyl) derivatives of cobalt and iron bis(dicarbollides) [8,8′-(MeS)₂-3,3′-M(1,2-C₂B₉H₁₀)₂]⁻ (M = Co, Fe) with copper, silver, palladium and rhodium leads to the formation of the corresponding chelate complexes, which is accompanied by a transition from the transoid to the cisoid conformation of the bis(dicarbollide) complex. This transition is reversible and can be used in design of coordination-driven molecular switches based on transition metal bis(dicarbollide) complexes. The solid-state structures of {(Ph₃P)ClPd[8,8′- (MeS)₂-3,3′-Co(1,2-C₂B₉H₁₀)₂-κ²-S,S′]} and {(COD)Rh[8,8′-(MeS)₂-3,3′-Co(1,2-C₂B₉H₁₀)₂-κ²-S,S′]} were determined by single crystal X-ray diffraction.