The distonic ion ˙CH2CH2CO+ and its formation from ionized cyclopentanone

Collisional activation decomposition (CAD) spectra are interpreted as indicating that formation of ˙CH₂CH₂CO⁺ (1) from ionized cyclopentanone, succinic anhydride arid butyrolactone is important at 70 eV electron energy. However, photoionization appearance energy measurements and CAD spectra demonstrate that CH₃CH?C?O^+· (3) is formed from ionized cyclopentanone near threshold. Ab initio molecular orbital calculations place ΔH _f (1) about 36 kJ mol^?1 above ΔH _f (3).     

Unimolecular reactions of the isolated immonium ions CH3CH = NH+C4H9, CH3CH2Ch = NH+C4H9 and (CH3)2C = NH+C4H9

The reactions of ten metastable immonium ions of general structure R¹R²C?NH⁺C₄H₉ (R¹ = H, R² = CH₃, C₂H₅; R¹ = R² = CH₃) are reported and discussed. Elimination of C₄H₈ is usually the dominant fragmentation pathway. This process gives rise to a Gaussian metastable peak; it is interpreted in terms of a mechanism involving ion-neutral complexes containing incipient butyl) cations. Metastable immonium ions ontaining an isobutyl group are unique in undergoing a minor amount of imine (R¹R²C?NH) loss. This decomposition route, which also produces a Gaussian metastable peak, decreases in importance as the basicity of the imine increases. The correlation between imine loss and the presence of an isobutyl group is rationalized by the rearrangement of the appropriate ion-neutral complexes in which there are isobutyl cations to the isomeric complexes containing the thermodynamically more stable tert-butyl cations. A sizeable amount of a third reaction, expulsion of C₃H₆, is observed for metastable n-C₄H₉ ⁺NH?CR¹R² ions; in contrast to C₄H₈ and R¹R²C?NH loss, C₃H₆ elimination occurs with a large kinetic energy release (40–48 kJ mol^?1) and is evidenced by a dish-topped metastable peak. This process is explained using a two-step mechanism involving a 1,5-hydride shift, followed by cleavage of the resultant secondary open-chain cations, CH₃CH⁺ CH₂CH₂NHCHR¹R².     

(CH2)2N和(CH3)2NH+的密度泛函理论计算

用密度泛函理论UB3LYP／6-31G（d,p）方法研究了二甲胺自由基（CH3）2N及其质子化离子（CH3）2NH 的构象和超精细结构．在由构象研究得到的两种自由基的最稳定结构上,用密度泛函的UB3LYP和UB3PW91方法及从头计算的UHF、UMP2（FULL）方法计算了α-质子、β-质子和N核上的超精细偶合常数A（Hα）、A（Hβ）和A（N）结果表明：两种自由基中甲基内旋转的位垒均很低,分别为0．46kJ·mol-1（（CH3）2NH ）和2．6kJ·mol-1（（CH3）2N）．UB3LYP／6-31G（d,p）和UB3PW91／6-31G（d,p）计算的A（Hα）、A（Hβ）和A（N）与ESR实验结果符合得很好,UMP2／6-31G（d,p）方法的计算值与实验值符合得也较好．     

Synthesis and Characterization of [NH3（CH2）2NH2（CH2）2NH3]BiCl6

1 INTRODUCTION During the past decade, a series of organic-inor- ganic hybrid compounds based on metal halide units have been prepared and studied[1]. The combination of organic and inorganic components at the mole- cular level affords us the opportunity to design new hybrid materials and modulate the properties of components[2]. As a result, some interesting proper- ties, such as non-linear optical[3], interesting magne- tic[4], efficient luminescence[2], ideal thermal and mechanical sta…     

Synthesis,characterization and some reactions of trans-[Co(NH3)4(CH3NH2)Br]2+ and trans-[Co(NH3)4(CH3NH2)(NO3)]2+ complexes

The preparation of trans-[Co(NH₃)₄(CH₃NH₂)Br]²⁺ and trans-[Co(NH₃)₄(CH₃NH₂)-(NO₃)]²⁺ complexes is described. The UV-VIS spectra of the complexes indicate a decrease of the ligand field compared to the parent pentaammines. Infrared spectra match with the pattern of the corresponding pentaammines. The catalyzed (by Hg²⁺) aquation of the trans-bromomethylamine complex go under retention of the stereochemical configuration. The base hydrolysis (studied at 25°C) products show trans to cis rearrangement for both complexes. ¹H NMR spectroscopy is used for identification of the stereochemical configuration of the compounds.     

Self-assembly of the octanuclear cluster [Cu8(OH)10(NH2(CH2)2CH3)12]6+ and the one-dimensional N-propylcarbamate-linked coordination polymer {[Cu(O2CNH(CH2)2CH3)(NH2(CH2)2CH3)3](ClO4)}n

The reaction of Cu(ClO4)2.6-H2O and n-propylamine in methanol gives two high-nuclearity products of well-defined compositions. At amine concentrations greater than seven equivalents compared to copper ion concentration, the system fixes carbon dioxide from air to form the one-dimensional carbamate-bridged coordination polymer, {[Cu(mu2-O,O'-O2CNH(CH2)2CH3)(NH2(CH2)2CH3)3](ClO4)}n ({1-ClO4}n). Lower relative amine concentrations lead to the self-assembly of an octanuclear copper-amine-hydroxide cluster [Cu8(OH)10(NH2(CH2)2CH3)12]6+ (2). Both compounds exhibit unique structures: {1-ClO4}n is the first mu2-O,O'-mono-N-alkylcarbamate-linked coordination polymer and 2 is the largest copper-hydroxide-monodentate amine cluster identified to date. The crystal structures indicate that the size of the n-propyl group is probably crucial for directing the formation of these compounds. Magnetic susceptibility studies indicate very weak antiferromagnetic coupling for 1. The octanuclear cluster 2 displays slightly stronger net antiferromagnetic coupling, despite the presence of a number of Cu-O(H)-Cu angles below the value of about 97 degrees that would normally be expected to yield ferromagnetic coupling.     

Synthesis and Characterization of （CH3CH2CH2CH2NH3）2SnBr6

1 INTRODUCTION Recently, the researches on inorganic-organic hy-brid compounds represent an advanced field in mate-rial science[1]. At the molecular level, the combina-tion of two extremely different components providesan avenue to design new hybrid materials as well asthe ability to modulate properties of one or more ofthe components[2～6]. Some attractive properties, suchas efficient luminescence[2～4], ideal thermal and me-chanical stability, interesting magnetic[5], non-linearoptical[…     

High-pressure- and low-temperature-induced changes in [(CH3)2NH(CH2)2NH3][SbCl5

The structure of N,N-dimethylethylenediammonium pentachloroantimonate(III), [(CH3)2NH(CH2)2NH3][SbCl5], NNDP, was investigated at 100 and 15 K at ambient pressure, as well as at pressures up to 4.00 GPa at room temperature in the diamond-anvil cell. The stable structure at low temperatures and low pressures consists of isolated [SbCl5]2- anions and [(CH3)2NH(CH2)2NH3]2+ cations. The inorganic anions have a distorted square pyramidal geometry. They are arranged in linear chains parallel to the c axis. In contrast to the low-temperature studies, where no phase transition was detected, pressure induces a P2(1)/c --> P2(1)/n phase transition between 0.55 and 1.00 GPa, accompanied by a doubling of the a unit-cell parameter. This solid-solid transition results from changes in the electron configuration of the Sb(III) atom and formation of the Sb-Cl bridging bonds between inorganic polyhedra to form, at approximately 1.0 GPa, isolated [Sb2Cl10]4- units consisting of [SbCl6]3- octahedra and [SbCl5]2- square pyramids connected by a common corner. The intermolecular distances continuously decrease with further increase in pressure, and at approximately 3.1 GPa, zigzag [{SbCl5}n]2n- chains containing corner-sharing [SbCl6]3- octahedra are formed. The unit-cell volume of NNDP decreases by 18.15% between room pressure and 4.00 GPa. The linear distortions of the [SbCl5]2- and [SbCl6]3- polyhedra decrease with increasing pressure and decreasing temperature and indicate a reduction in the stereochemical activity of the lone electron pair on the Sb(III) atom.     

Investigating the two inequivalent NH2(CH3)2 ions in [NH2(CH3)2]2CuCl4 using magic angle spinning nuclear magnetic resonance

The structural change near the phase transition temperatures of [NH₂(CH₃)₂]₂CuCl₄ is discussed in terms of the chemical shifts and the spin-lattice relaxation times T_1ρ in the rotating frame for ¹H MAS NMR and ¹³C CP/MAS NMR. The ¹H T_1ρ undergoes molecular motion near the phase-transition temperature (T_C2 = 253 K). In addition, the two inequivalent [NH₂(CH₃)₂] (1) and [NH₂(CH₃)₂] (2) sites were distinguishable by the ¹³C chemical shift. And, the most significant change was observed at T_C2 for the ¹³C CP/MAS NMR spectrum; this temperature corresponds to a ferroelastic phase transition with different orientations.     

Heat of formation for the CH3CH=NH2+ cation by photoionization mass spectrometry

The m/z 44 appearance energies for five primary amines have been measured by threshold photoionization mass spectrometry. Following an analysis of the thermochemistry associated with these unimolecular fragmentations, a value of 665.1 +/- 1.4 kJ mol(-1) is obtained for the 298 K heat of formation for the ethylidenimmonium cation (CH(3)CH=NH(2)(+)). When combined with high-level ab initio calculations, this results in absolute proton affinities of 906.4 +/- 2.7 and 909.2 +/- 2.8 kJ mol(-1) for the ethylidenimines E-CH(3)CH=NH and Z-CH(3)CH=NH, respectively.     

The distonic ions HO+CHCH2C˙H2 and CH3C(O+H)CH2C˙H2

The distonic ions HO⁺?CHCH₂C^˙H₂ (1) and CH₃C(?O⁺H)CH₂C^˙H₂ (2) were directly generated, their decompositions characterized and their appearance energies determined by photoionization. Heats of formation derived from the appearance energies were 757 kJ mol^?1 for 1 and 692 kJ mol^?1 for 2. Deuterium labeling demonstrates that both ions decompose at low energies in the same ways as their isomers with the same skeletal structures, consistent with proposals that 1 and 2 are intermediates in the decompositions of those systems. Surprisingly, the values of the translational energy releases accompanying the formation of CH₃CO⁺ and C₂H₅CO⁺ from 2 appear to be inversely proportional to the available excess energy. The 1,2-H-shift RC(?O⁺H)CH₂C˙H₂ → RC(?O₊H)C˙HCH₃ is compared to the corresponding, non-occurring 1,2-H-shift in alkyl free radicals.     

链状[NH3CH2CH2NH3]AgAsS4的溶剂热合成及表征

利用溶剂热方法合成了链状[NH3CH2CH2NH3]AgAsS4,通过单晶X射线衍射技术对其进行了晶体结构分析,该化合物晶体属单斜晶系,空间群C2/c,晶胞参数a=1.35805(8)nm,b=0.65331(3)nm,c=2.27711(9)nm,β=106.42(3)°,Z=8.化合物具有有趣的梯子状双链结构,该阴离子链由AsS4与AgS3共用顶点交替连接而成,有机阳离子在阴离子链之间存在较强的N—H…S氢键.DSC和Tg分析结果表明化合物在200℃以下是稳定的.     

[(NH2CH2CH2NH3)2WⅥO2(NHC6H4NH)2]2(NH2CH2CH2NH2)·H2O配合物的合成与晶体结构

Cis-dioxo-tungsten(Ⅵ) complex, (NH₂CH₂CH₂NH₂)[(NH₂CH₂CH₂NH₃)₂W^ⅥO₂(NHC₆H₄NH)₂]₂·H₂O is synthesized at room temperature by the reaction of sodium tungstate with o-phenylenediamine. The crystal structure of complex was determined by X-ray diffraction structural analysis. The results show that complex belongs to monoclinic system with space group P2₁/ c, a=0.712 8(2) nm, b=3.081 1(10) nm, c=0.981 9(3) nm, β=102.615(4)°, V=2.104 4(11) nm³, Z=2, μ=55.26 cm^-1, F(000)=1 176. Compared the complex with its analogous biomimetic complexes of the cofactor of molybdoenzymes and tungstoenzymses, it is found that the variance of the coordination atoms and the metal ions center have no influence on the coordination feature, and exhibits distored octahedral coordination with cis-dioxo o-phenylenediamine. CCDC: 252834.     

Interpretation der Schwingungsspektren von (CH3)2SO2, (CH3)2SO(NH) und (CH3)2S(NH)2 unter Verwendung eines Kopplungsstufenverfahrens

Normal Coordinate Analysis of (CH₃)₂SO₂, (CH₃)₂SO(NH), and (CH₃)₂S(NH)₂ using the Method of Stepwise Coupling The qualitative assignment of the vibrational spectra of (CH₃)₂SO₂ ( 1 ), (CH₃)₂SO(NH) ( 2 a ), and (CH₃)₂S(NH)₂ ( 3 a ) and of the C and N deuterated derivatives of 2 a and 3 a is used in a normal coordinate analysis by the method of stepwise coupling. The force constants and the energy distributions are calculated in symmetry coordinates using a generalized valence force field.     

[In2(HPO3)4]·(NH3CH2CH2NH3)的水热合成与晶体结构

用乙二胺作模板剂在水热条件下合成出一个新的三维开放骨架结构的亚磷酸铟[In2(HPO3)4]·(NH3CH2CH2NH3)(1), 并对其晶体结构进行了测定和表征.     

Synthesis and Structure of a One‐Dimensional Aluminum Phosphate, [NH3(CH2)2NH2(CH2)3NH3]3+ [Al(PO4)2]3—

A one‐dimensional aluminum phosphate, [NH₃(CH₂)₂NH₂(CH₂)₃NH₃]³⁺ [Al(PO₄)₂]^3—, has been synthesized hydrothermally in the presence of N‐(2‐Aminoethyl‐)1, 3‐diaminopropane (AEDAP) and its structure determined by single crystal X‐ray diffraction. Crystal data: space group = Pbca (no. 61), a = 16.850(2), b = 8.832(1), c = 17.688(4)Å, V = 2632.4(2)ų, Z = 8, R₁ = 0.0389 [5663 observed reflections with I > 2σ(I)]. The structure consists of anionic [Al(PO₄)₂]^3— chains built up from AlO₄ and PO₄ tetrahedra, in which all the AlO₄ vertices are shared and each PO₄ tetrahedron possesses two terminal P=O linkages. The cations, which balances the negative charge of the chains, are located in between the chains and interact with the oxygen atoms through strong N—H···O hydrogen bonds. Additional characterization of the compound by powder XRD and MAS‐NMR has also been performed and described.     

Synthesis of a layered zinc phosphate, [NH3(CH2)2NH2(CH2)3NH3][Zn2(PO4)(HPO4)2].H2O,and its transformation to a extra-large pore three-dimensional zinc phosphate, [NH3(CH2)2NH2(CH2)3NH3][Zn3(PO4)(HPO4)3

An unusual two-dimensional zinc phosphate with pendant phosphate groups, projecting into the inter-lamellar space between the layers, has been synthesized and is shown to transform into a three-dimensional structure with 16-membered bifurcated channels, giving evidence for the building up process in the formation of open-framework structures.