Sm°/Cat. I2 and SmI2 induced reductive coupling of nitriles with azides

The intermolecular reductive coupling of nitriles with azides induced by Sm°/Cat. I₂ or SmI₂ was studied. Aromatic and aliphatic amidines were prepared in moderate to good yields under neutral and mild conditions respectively.     

The Structure of Gaseous Carbon Tetraiodide from Electron Diffraction and All Carbon Iodides,CIn (n = 1–4), and Their Dimers,C2I2n (n = 1–3) from High-Level Computation. Any Other Carbon-Iodide Species in the Vapor?

The geometry of a series of carbon iodides have been determined, CI₄ by gas-phase electron diffraction and CI _n (n = 1–4) and C₂I_2n (n = 1–3) by high-level quantum chemical calulations. The bond length of the tetrahedral CI₄ molecule from electron diffraction is (r _g):2.157(10) Å. The indication of about 20% I₂ in the vapor suggests partial decomposition and it has been thoroughly investigated what other carbon iodide species might be present beside CI₄. There is no appreciable amount of either of the dimeric species in the vapor phase, in spite of the suggestion from thermodynamics. On the other hand, the electron diffraction data are compatible with the presence of about 18% of either of the monomeric free radicals, CI₃ or CI₂, beside CI₄ and I₂. Possible reasons for these observations are discussed. Our correlated level computations, in agreement with other high level computations, found the singlet ¹A₁ state to be the ground state for CI₂. This is in contrast with a recent photoelectron spectroscopic study according to which the triplet state is the ground state though with a large margin of error (1 ± 3 kcal/mol energy difference). The computed singlet-triplet separation strongly depends on the level of the computation, but it is at least 9 kcal/mol. Geometrical parameters, singlet-triplet separations, and dipole moments have been calculated for the CX₂ series (X = F, Cl, Br, I, H) and their variations are discussed. The thermodynamic stability of different carbon iodide species has also been investigated.     

邻-二氨基烯的合成新方法

以芳香醛,硫和胺为起始原料,经Willgerodt—Kindler反应合成硫代酰胺,硫代酰胺在钐／二碘化钐试剂促进下发生脱硫偶联反应,得到邻-二氨基烯类化合物。其结构经1^H NMR,IR,MS和元素分析表征。     

An Unusual Heterobimetallic Disiloxanediolate Cluster of Samarium(III)

The reaction of samarium(II) diiodide with in situ prepared disodium‐1,1,3,3‐tetraphenyl‐1,3‐disiloxanediolate, [(Ph₂SiONa)₂O], afforded the unusual heterobimetallic samarium(III) disiloxanediolate cluster [Me₃SiO{μ‐Na(THF)}₃Sm{μ‐(Ph₂SiO)₂O}₃Na(THF)] ( 1 ) in low yield. A single‐crystal X‐ray structure determination of 1 revealed the presence of a polycylic inorganic ring system in which the samarium atom is not only chelated by three [(Ph₂SiO)₂O]^2? ligands but is also part of a SmNa₃O₄ heterocubane cage.     

Electrochemical activation of the alkylation of GeI2 byn-butyl bromide and methylcobalt(iii) bisdimethylglyoximate

The mechanism of the alkylation of GeI₂ byn-butyl bromide and methylcobalt(iii) bisdimethylglyoximate in acetonitrile was studied using cyclic voltammetry. The reaction with the methylcobalt complex occursvia anodic activation (oxidation of the methylcobalt complex), while the reaction withn-butyl bromide is initiated by cathodic activation (reduction of GeI₂). Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2157–2160, December, 1997.     

Development of novel and efficient synthesis of group 14 element (Ge and Sn) catenates by use of samarium (II) diiodide

Group 14 element catenates such as di-, tri-, poly-germanes, and polystannanes are efficiently synthesized by use of the one-electron reducing agent SmI₂ under mild homogeneous conditions in good yields.     

Diastereoselective Hydroxyethylation of β‐Hydroxyketones: A Reformatsky Cyclization‐Lactone Reduction Cascade Mediated by SmI2−H2O

The hydroxyethylation of β‐hydroxyketones allows diastereoselective access to important 1,3,5‐triols. The approach exploits a SmI₂?H₂O‐mediated Reformatsky cyclization‐lactone reduction cascade.     

二碘化钐有效催化芳胺成胍反应的研究

二碘化钐作为易得的路易斯酸型预催化剂,可有效催化芳胺和碳二亚胺的反应,在温和条件下以高收率得到一系列胍。