[2+3]Cycloaddition reaction of a kinetically stabilized distibene with a nitrile oxide leading to the formation of a unique heterocyclic compound

The synthesis of a 1-oxa-5-aza-2,3-distibacyclopent-4-ene derivative by the [2+3]cycloaddition reaction of a kinetically stabilized distibene, BbtSb=SbBbt (Bbt = 2,6-bis[bis(trimethylsilyl)methyl]-4-[tris-(trimethylsilyl)methyl]phenyl), with MesCNO (Mes = mesityl) has been performed. Dedicated to Prof. Dr. E. Lukevics on the occasion of his 70th birthday __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1880–1887, December, 2006.     

甲基丙烯酸镁增强氢化丁腈橡胶的结构与形态和性能

用不同份量的甲基丙烯酸镁(MgMA)作增强剂,过氧化二异丙苯(DCP)作硫化剂,通过混炼和硫化过程的原位聚合制备了氢化丁腈橡胶/聚甲基丙烯酸镁(HNBR/PMgMA)纳米复合材料,用XRD、FTIR1、3C-NMR、SEM、TEM、DMA和交联密度分析等方法研究了其结构、形态和性能,并阐述了MgMA改性HNBR的相关机理.结果表明,MgMA在混炼过程中粒径明显变小,部分达到纳米级.硫化过程中发生原位自由基聚合,并部分接枝到HNBR分子链上,HNBR硫化胶和PMgMA有可能形成接枝互穿聚合物网络(接枝IPN).随着MgMA用量的增加,纳米复合材料硫化胶的定伸应力、拉伸强度、扯断伸长率、撕裂强度和热氧老化性能逐渐提高.当MgMA含量为30份时,体系的拉伸强度和扯断伸长率分别为38.5MPa和545%,并具有优异的热空气老化性能.MgMA能明显增加HNBR复合材料的储能模量,并降低其损耗因子.随着MgMA用量的增加,纳米复合材料硫化胶的总交联密度(Ve)和离子键交联密度(Ve2)增加,而共价键交联密度(Ve1)下降,表明离子键对HNBR/PMgMA纳米复合材料的力学性能起重要作用.     

Crystal structure of chloro(dicarbonyl) bis(acetonitrile) (π-2-methallyl) molybdenum(II)

The title compound crystallizes in the monoclinic spacegroup P2₁/m with a = 6.796(9), b = 12.145(14), c = 7.749(8)Å, = 101.86(1)°, and Z = 2. The crystal structure consists of molecules of [MoCl(CO)₂(NCMe)₂(³-C₃H₄Me-2)] with crystallographically imposed C_s symmetry and has a pseudo-octahedral geometry, with the -allyl group trans- to the chloro group and the two cis-carbonyl and acetonitrile groups occupying the equatorial plane.     

双二茂铁基(三甲硅烷氧基)乙腈的合成与晶体结构

双二茂铁甲酮与三甲基氰硅烷在CH2Cl2中ZnI2催化下加成,得到产率较高的双二茂铁基(三甲硅烷氧基)乙腈,用元素分析、IR和1HNMR进行了表征。经X-射线单晶衍射法测试表明,该化合物属单斜晶系,P21/c空间群,化学式为C25H27Fe2NOSi,独立衍射点10698个,可观察衍射点6552个(I>2s(I)),Mr=492.27,a=13.8197(13),b=20.0937(18),c=17.1269(16),b=105.114(2)埃琕=4591.4(7)?,Z=8,Dc=1.439g/cm3,(MoK?=1.332mm-1,F(000)=2064,最终偏离因子R=0.0410、wR,=0.0705。     

Cobalt(III)-catalyzed cycloaddition polymerization of diynes with nitriles: Synthesis of polymers containing pyridine moieties in the main chain

The synthesis of pyridine-containing polymers was carried out by the cycloaddition of diynes with nitriles in the presence of organocobalt complexes as catalysts. As a model experiment, the pyridine-formation reaction of monofunctional acetylenes with nitriles was reexamined in detail in the presence of organocobalt catalysts, from which the combination of terminal aliphatic acetylenes and aromatic nitriles was proved to be suitable for the specific pyridine-formation process. On the basis of this result, the polymerization of terminal aliphatic diynes with aromatic nitriles was carried out in the presence of the cobalt catalyst (10 mol %) to give polymers containing substituted pyridine moieties in the main chain in high yields. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1979–1986, 1999     

Hydrierung aromatischer Nitrile auf dem Fe3(CO)9-Cluster

Hydrogenation of Aromatic Nitriles on the Fe₃(CO)₉ Cluster The μ₃-nitrile bridged clusters Fe₃(CO)₉(μ₃-η²-N≡CR) ( 3 , R = phenyl, p-tolyl, p-anisyl) consume hydrogen upon heating in solution with formation of the acimidoyl- and the alkylideneimido-bridged clusters HFe₃(CO)₉(μ₃-η²-HN=CR) ( 1 ) and HFe₃(CO)₉(μ₃-η²-N=CHR) ( 2 ). These can be obtained in a better way by successive H⁺ and H^– addition with NaBH₄ and H₃PO₄. HFe₃(CO)₉(μ₃-η²-N=CHR) ( 2 ) adds P(OMe)₃ with concomitant hydrogen migration to form Fe₃(CO)₉P(OMe)₃(μ₃-η¹-N–CH₂R) ( 6 ). The phosphite-substituted cluster Fe₃(CO)₈P(OMe)₃(μ₃-η²-N≡CPh) ( 5 a ) on the other hand is converted by the H⁺/H^– addition to the products HFe₃(CO)₈P(OMe)₃(μ₃-η²-HN=CPh) ( 7 a ) and HFe₃(CO)₈P(OMe)₃(μ₃-η²-N=CHPh) ( 8 a ).