Substituted 2-methyl- and 2-methyleneindolines. 2. Nitro- and amino-substituted 2-methyl- and 2-methylene-indolines

From 5- and 6-aminotetramethylindolines, 2-methyleneindolines have been synthesized; these compounds can be condensed with other heterocyclic systems. The nitration of 1,2,3,3-tetramethylindoline under different conditions was studied.For communication 1, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 919–923, July, 1989.     

Sc2MgGa2 and Y2MgGa2

Scandium magnesium gallide, Sc₂MgGa₂, and yttrium magnesium gallide, Y₂MgGa₂, were synthesized from the corresponding elements by heating under an argon atmosphere in an induction furnace. These intermetallic compounds crystallize in the tetragonal Mo₂FeB₂‐type structure. All three crystallographically unique atoms occupy special positions and the site symmetries of (Sc/Y, Ga) and Mg are m2m and 4/m, respectively. The coordinations around Sc/Y, Mg and Ga are pentagonal (Sc/Y), tetragonal (Mg) and triangular (Ga) prisms, with four (Mg) or three (Ga) additional capping atoms leading to the coordination numbers [10], [8+4] and [6+3], respectively. The crystal structure of Sc₂MgGa₂ was determined from single‐crystal diffraction intensities and the isostructural Y₂MgGa₂ was identified from powder diffraction data.     

2-stannaindenes and 2-stannaindanes

Condensation of o-xylylene bis(triphenylphosphorane) 4 with [(Me₃Si)₂N]₂Sn yields the 1,3-bis(triphen-ylphosphoranediyl)-2σ²-stannaindene 2 , which is orange as a solid and red in solution and which demonstrates stannylene reactivity. Alkyl bromides andiodides add to 2 to give the corresponding 2σ⁴-stannaindanes. In the reaction with PCl₃, the tin atom in 2 is replaced by a phosphenium ring member. A secondary product in the preparation of 2 is the spirocyclic 2σ⁴-stannaindane 12. Its structure has been determined by X-ray analysis. © 1998 John Wiley & Sons, Inc. Heteroatom Chem 9:103–108, 1998     

Structure and properties of single crystalline CaMg2Bi2, EuMg2Bi2, and YbMg2Bi2

Single crystals of CaMg(2)Bi(2), EuMg(2)Bi(2), and YbMg(2)Bi(2) were obtained from a Mg-Bi flux cooled to 650 °C. These materials crystallize in the CaAl(2)Si(2) structure-type (P ?3m1, No. 164), and crystal structures are reported from refinements of single crystal and powder X-ray diffraction data. EuMg(2)Bi(2) displays an antiferromagnetic transition near 7 K, which is observed via electrical resistivity, magnetization, and specific heat capacity measurements. Magnetization measurements on YbMg(2)Bi(2) reveal a weak diamagnetic moment consistent with divalent Yb. Despite charge-balanced empirical formulas, all three compounds are p-type conductors with Hall carrier concentrations of 2.0(3) × 10(19) cm(-3) for CaMg(2)Bi(2), 1.7(1) × 10(19) cm(-3) for EuMg(2)Bi(2), and 4.6(7) × 10(19) cm(-3) for YbMg(2)Bi(2), which are independent of temperature to 5 K. The electrical resistivity decreases with decreasing temperature and the resistivity ratios ρ(300 K)/ρ(10 K) ≤ 1.6 in all cases, indicating significant defect scattering.     

The alkali hypophosphites KH2PO2, RbH2PO2 and CsH2PO2

The structures of the hypophosphites KH₂PO₂ (potassium hypophosphite), RbH₂PO₂ (rubidium hypophosphite) and CsH₂PO₂ (caesium hypophosphite) have been determined by single‐crystal X‐ray diffraction. The structures consist of layers of alkali cations and hypophosphite anions, with the latter bridging four cations within the same layer. The Rb and Cs hypophosphites are isomorphous.     

Synthesis and reactions of 2-chloro- and 2-tosyloxy-2'-deoxyinosine derivatives

Convenient syntheses of 2-chloro- and 2-tosyloxy-2'-deoxyinosine as their tert-butyldimethylsilyl ethers are described. Both compounds can be synthesized via a common route and rely on commercially available 2'-deoxyguanosine. The present method leading to the chloro nucleoside is operationally simpler compared to previously reported glycosylation techniques where isomeric products were obtained. Both electrophilic nucleosides can be used for the preparation of N-substituted 2'-deoxyguanosine analogues via displacement of the leaving groups, and a comparison of their reactivities shows the chloro analogue to be superior. Interestingly, a Pd catalyst-mediated, two-step, one-pot conversion of an allyl-protected chloro nucleoside intermediate to the final modified 2'-deoxyguanosine derivatives is also feasible. On the basis of these observations, initial assessments of Pd-catalyzed aryl amination as well as a C-C cross-coupling have also been performed with the chloro and tosyloxy nucleoside substrates. Results indicate a potentially high synthetic utility of 2-chloro-2'-deoxyinosine and in many instances this derivative can supplant the bromo and fluoro analogues that are more cumbersome to prepare or are not readily available.     

Homopolymerization of 2-alkyl- and 2-aryl-2-oxazolines

2-Aryl- and 2-alkyl-2-oxazolines have been polymerized to poly-(N-aroyl)aziridines and poly(N-acyl)aziridines, respectively, in the presence of boron trifluoride. The polymers obtained were glassy, light yellow resins with molecular weights ranging from 3500 to 7500 (35–50 oxazoline units per chain). The polymerization rates have been determined for several of these monomers. A polymerization mechanism is proposed.     

Electronic structure and spectrum of UO2 2+ and UO2Cl4 2-

A theoretical study is presented of the electronic spectra of the UO(2) (2+) and UO(2)Cl(4) (2-) ions, based on multiconfigurational perturbation theory (CASSCF/CASPT2), combined with a recently developed method to treat spin-orbit coupling [P.-A. Malmqvist et al., Chem. Phys. Lett. 357, 230 (2002); B. O. Roos and P.-A. Malmqvist, Phys. Chem. Chem. Phys. 6, 2919 (2004)]. The results are compared to the experimental spectroscopic data obtained for uranyl ions in Cs(2)UO(2)Cl(4) crystals from Denning [Struct. Bonding (Berlin) 79, 215 (1992)] and to previous theoretical calculations performed using a combined configuration-interaction spin-orbit treatment [Z. Zhang and R. M. Pitzer, J. Phys. Chem. A 103, 6880 (1999); S. Matsika and R. M. Pitzer, J. Phys. Chem. A. 105, 637 (2001)]. As opposed to the latter results, the calculations performed in this work point to a significant effect of the weakly bound equatorial chlorine ligands on the excitation energies.     

Substituted 2-methyl- and 2-methylenindolines

Methods were developed to convert 1,2,3,3-tetramethyl-6-hydroxyindoline into coumarin dyes, in which the amino group is in the indoline system. The structure of the products was indicated by ¹H and ¹³C NMR spectroscopy.Communication 4, see ref. [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1614–1616, December 1992.     

O2 和 CO 在 Co2B2/TiO2 和 Co2B2Pt/TiO2 表面吸附的密度泛函研究

 采用密度泛函理论探讨了 TiO2 表面负载 Co2B2 和 Co2B2Pt 合金簇可能的负载构型. 结果表明, Co2B2 和 Co2B2Pt 合金簇倾向于以两个 Co 的形式负载在两个氧上. 态密度分析发现, 负载后, Co2B2 合金簇中部分 Co 原子和 B 原子成键加强, Co2B2Pt 合金簇中 Pt 原子和 B 原子成键也加强, 形成新的轨道. CO 和 O2 在 Co2B2/TiO2 和 Co2B2Pt/TiO2 表面吸附的结果表明, Co2B2Pt/TiO2 催化氧化 CO 性能的提高是由于 Pt 原子提高了 Co2B2 合金簇吸附 CO 和 O2 的能力.     

Stereoselective synthesis of 2-deoxy-beta-galactosides via 2-deoxy-2-bromo- and 2-deoxy-2-iodo-galactopyranosyl donors

[reaction: see text] A series of 2-bromo- and 2-iodo-galactopyranosyl acetates and trichloroacetimidates were evaluated as glycosyl donors for the synthesis of 2-deoxygalactopyranosides. The best selectivity for the beta-glycosidic linkage was achieved by using 6-deoxy-3,4-carbonate-protected galactosyl donors.     

Volatile ZnPhen(S2CNEt2)2 and MnPhen(S2CNEt2)2 complexes and the MnZn2Phen3(S2CNEt2)6 phase: Thermal behavior and crystal and molecular structures of two modifications of ZnPhen(S2CNEt2)2

Two crystal modifications, I and II, of the ZnPhen(S₂CNEt₂)₂ complex have been isolated. According to XRD data, the single crystals of I are triclinic with a=9.745(2), b=10.252(2), c=14.331(3) Å, α=99.18(2), β=91.01(2), γ=113.28(2)°, V=1293.2(4) ų, space group P1, Z=2, d_calc=1.401 g/cm³. The crystals of II are monoclinic with a=7.220(6), b=18.095(2), c=19.050(4) Å, β=95.85(2)°, V=2475.8(7) ų, space group C2/c, Z=4, d_calc=1.461 g/cm³. In both modifications, the structure is formed by monomer molecules with a distorted octahedral environment of the zinc atom. All atoms in I are in the general position; in II, the atoms are linked by the twofold rotation axis. It is shown by X-ray phase analysis (XRPA) that the MnPhen(S₂CNEt₂)₂ complexes (III) are isostructural to modification I of the ZnPhen(S₂CNEt₂)₂ complex, which underlies the synthesis of a solid solution of these complexes, MnZn₂Phen₃(S₂CNEt₂)₆ (phase IV). It is found that MPhen(S₂CNEt₂)₂ (M=Zn²⁺, Mn²⁺) and phase IV quantitatively sublime when heated in vacuum. Thermolysis of III in argon yields manganese(II) sulfide of cubic modification; the main product of thermolysis of phase IV is a solid solution of Zn_xMn_1?xS of hexagonal modification.     

Gaseous HgH2, CdH2, and ZnH2

Gaseous HgH2, CdH2, and ZnH2 molecules were synthesized by the direct gas-phase reaction of excited mercury, cadmium, and zinc atoms with molecular hydrogen. The molecules were identified by their high-resolution infrared emission spectra, and the metal-hydrogen bond lengths were determined from the rotational analysis of the antisymmetric stretching fundamental bands.     

Reactions of 2-amino- and 2-hydrazinobenzimidazoles with 2-acyldimedones

The reaction of 2 formyldimedone with 2-amino- and 2-hydrazinobenzimidazoles at 20°C in ethanol gave 2-(2-benzimidazolyl)aminomethylene- and 2-[2-(2-benzimidazolyl)hydrazinomethylene]-5,5-dimethylcylohex-anediones, while this reaction carried out in ethanol at reflux in the presence of acid gave 2,2-dimethyl-4-oxo 1, 2, 3, 4-tetrahydroquinazolino(1, 2-a]benzimidazole and 1-(2-benzimidazolyl)-6, 6-dimethyl-4-oxo-4, S, 6, 7-tetrahydroindazole, respectively.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 247–252, February, 1996.