C-H…O Hydrogen Bonds and π…π Interaction and the Crystal and Molecular Structures of 3-Nitro-benzylideneaniline-methyl-2’

The title compound (C14H12N2O2, Mr = 240.26) crystallizes in the monoclinic system, space group P21/a with a = 7.394(1), b = 21.334(3), c = 7.423(1) ? b = 89.82(1)? V = 1170.8(3) ?, Z = 4, Dc = 1.363 g/cm3, m(MoKa) = 0.93 cm-1 and F(000) = 504.00. The final R and wR are 0.0440 and 0.1370 for 2153 observed reflections (I > 2s(I)), respectively. The dihedral angle between the two phenyl rings is 52.9 and that between the NO2 group and its attached ring is 3.0. In the crystal, molecules are stacked along [100] through p…p interactions. The CH…O hydrogen bond (3.403 ? 120.4? laterally connects the stacks along [010] to form networks (001) which are further anti- parallelly connected by CH…O (3.382 ? 142.9) and p…p interactions extending along [001]. Also presented here is a brief study on the CH…O hydrogen bonds in nitro-substituted benzyl-ideneanilines which can be classified into five types, namely, )5(12R, )4(21R, )8(22R, )6(12R and )7(22R, with the first three occurring more often.

Synthesis, Crystal Structure and Antimicrobial Activity of {[Bis(pyridine-κN)bis(3,5-dinitrosalicylato κ-O,O')Zn(Ⅱ)][bis(pyridine-κN)Zn(Ⅱ)]}

A novel {[bis（pyridine-κN）bis（3,5-dinitrosalicylato κ-O,O＇）Zn（Ⅱ）][bis（pyridine-κN）Zn（Ⅱ）]}（C_（34）H_（24）N_8O_（14）Zn_2） was synthesized by a self-assemble method at room temperature. The molecular structure was determined by single-crystal X-ray analysis. The compound crystallizes in the monoclinic system, space group P2_1/n with a = 12.2156, b = 13.5696, c = 22.5602 A, β = 90.061o, Z = 4 and V = 3739.6（3）A^3. The new 1D binuclear coordination polymer {[bis（py-κN）bis（3,5-dinitrosal κ-O,O′） Zn（Ⅱ）][bis（py-κN）Zn（Ⅱ）]} resulted from two different types of moieties. The polymer [bis（py-κN）bis（3,5-dinitrosal κ-O,O′）Zn（Ⅱ）] unit is connected with [bis（py-κN） Zn（Ⅱ）] by zigzag topology. One zinc（Ⅱ） cation has a six-fold coordination environment, in which the metal atom is connected with four oxygen atoms of two 3,5-dinitrosalicylic acids to form equatorial bonds and two nitrogen atoms of pyridine to generate the axial bonds. Other four-fold nucleus contain two Zn-O bonds from different 3,5-dinitrosalicylic acids and two bonds with the Natom of pyridine. Antimicrobial assay results indicated that the compound showed moderate activities against different bacterial and fungal strains.

Synthesis,Crystal Structure and Bioactivity of 1-(3-((Benzo[d][1,3]dioxol-5-yloxy)methyl)-phenethyl)-4-phenylpiperidin-4-ol

The title compound 1-（3-（（benzo[d][1,3]dioxol-5-yloxy）methyl）phenethyl）-4- phenylpiperidin-4-ol （4, C27H29NO4, Mr = 431.51） was synthesized by a four-step reaction and characterized by 1H NMR, 13C NMR, elemental analysis and single-crystal X-ray diffraction. The crystal is of triclinic, space group P1 with a = 5.8033（12）, b = 10.705（2）, c = 18.393（4）A, a = 83A4（3）, β = 82.71（3）, γ = 88.88 （3）°, V= 1126.0（4） A3, Z= 1, Dc= 1.273 g/cm3, S = 1.070, p = 0.681 mm^-1, F（000） = 460, R = 0.0618 and wR = 0.1619 for 6452 observed reflections with I 〉 2σ（I） Geometry conformations revealed that the dihedral angle between benzodioxole and aromatic planes contributed to the formation of C-H…π interactions. Hydrogen bonds and van der waals interactions were observed to stabilize the three-dimensional packing structure. The compound showed a moderate inhibitory activity against the prostate cancer cells.

Synthesis,Spectroscopic Properties and Crystal Structure of 3,3'-(Anthracene-9,10-diyl)bis(1-phenylpropan-1-one)

The compound 3,3＇-（anthracene-9,10-diyl）bis（1-phenylpropan-1-one）（C32H26O2,Mr=442.55） has been synthesized by the reaction of 2,2＇-（anthracene-9,10-diylbis（methy-lene））bis（1,3-diphenylpropane-1,3-dione） with CsCO3,and its structure was characterized by 1H NMR and single-crystal X-ray diffraction.The crystal of the title compound belongs to monoclinic,space group P21/c with a=9.154（3）,b=5.2777（16）,c=24.897（7） nm,β=107.337（10）°,Z=2 and V=1.1482 nm3.X-ray analysis indicates that an intermolecular hydrogen bond C（8）-H（8A）…O（1）,weak C-H···π between H（9A） and the centre of anthracene rings and weak π-π interactions between two anthracene ring planes are observed.

Molecular and Crystal Structure of 1,3,5-Tris(benzimidazol- 1-ylmethyl)-2,4,6-Trimethylbenzene

The compound 1,3,5-tris(benzimidazol-1-ylmethyl)-2,4,6-trimethylbenzene, crystallizes in the monoclinic system, space group P21/c, with a = 17.571(4), b = 10.860(2), c = 14.126(3) ?; ( = 92.89(3)(, V = 2692(1) ?3, Dc = 1.260 g/cm3, Z = 4, C33H30N6, Mr = 510.63, ((MoK() = 0.077mm-1, F (000) = 1080. The structure was refined to R = 0.0592, wR = 0.1379 for 1492 (I(2((I)) reflections. The title molecule has cis, trans, trans-conformation about the central phenyl ring. The screw-related molecules are connected by hydrogen bonds C-H(((N (x, -0.5-y, 0.5+z) and form the infinite helical chains. The polar molecular chains are antiparallelly stacked through edge-to-face C-H…πinteractions.

Synthesis and Crystal Structure of S,S'-Bis(8-quinolyl)-1,8-dithiaoctane

The title compound S,S?bis(8-quinolyl)-1,8-dithiaoctane crystallizes in the monoclinic system, space group P21/n with a = 7.537(1), b = 20.434(3), c = 13.857(2) , = 97.102(3)? V = 2117.8(5) 3, Dc = 1.269 g/cm3, Z = 4, C24H24N2S2, Mr = 404.57, (MoK? = 0.263 mm-1 and F(000) = 856, and its structure was refined to R = 0.0417 and wR = 0.1077 for 2814 observed reflections (I > 2(I)). The compound crystallizes in conformations A and B with equal occupation ratio. A acts as both a donor and acceptor in the CH… interactions, but B only acts as a donor. Edge-to-face CH…?interactions between AA along the a axis and BABA along the c axis result in an infinite layered-structure in the ac plane.

Site-specific deposition creates electron-rich Pd atoms for unprecedented C-H activation in aerobic alcohol oxidation

Here,we demonstrate a photochemical strategy to site-specifically deposit Pd atoms on Au nanoparticles.The high-sensitivity low-energy ion scattering spectra combined with the X-ray photoelectron spectra reveal that the surface electronic structure of Pd can be continuously regulated by tailoring the Pd-to-Au molar ratio and the location of Pd atoms in Au Pd nanoparticles.It is revealed that electron-rich Pd atoms are considerably more active than the net Pd atoms in aerobic alcohol oxidation.Remarkably,the catalyst with the most electron-rich Pd sites(binding energy downshift:1.0 e V)exhibits an extremely high turnover frequency(~500000 h-1 vs 12000 h-1 for that with net Pd atoms)for solvent-free selective oxidation of benzyl alcohol,which is,to the best of our knowledge,the highest value ever reported.Kinetic studies reveal that electron-rich Pd atoms can accelerate the oxidation of benzyl alcohol by facilitating C-H cleavage,as indicated by the significant reduction in the activation energy as compared to net Pd atoms.

Investigation of Intermolecular C-H···Halogen Hydrogen Bonded Supramolecular Assemblies in Three Copper(Ⅰ) Complexes Formed by 3,3'-Dimethoxy-6,6'-dimethyl-2,2'-bipyridine Ligand

Three new crystalline compounds 1-3 were successfully obtained by the reactions of 3,3＇-dimethoxy-6,6＇-dimethyl-2,2＇-bipyridine ligand（dmbp） with the corresponding Cu（Ⅰ） salts.Crystal data for 1：orthorhombic Pbca,a = 18.5858（12）,b = 8.1821（5）,c = 20.6066（13） ,V = 3133.7（3） 3,Z = 8,Dc = 1.843 g/cm3,F（000） = 1696,μ = 3.366 mm-1,the final R = 0.0223 and wR = 0.0542.Crystal data for 2：Orthorhombic Pbca,a = 18.7883（16）,b = 8.3249（7）,c = 19.0294（17） ,V = 2976.4（4） 3,Z = 8,Dc = 1.731 g/cm3,F（000） = 1552,μ = 4.154 mm-1,the final R = 0.0279 and wR = 0.0680.Crystal data for 3：monoclinic P21/c,a = 13.812（10）,b = 9.910（7）,c = 23.444（17） ,β = 104.3350（10）°,V = 3090（4） 3,Z = 4,Dc = 1.476 g/cm3,F（000） = 1408,μ = 1.588 mm-1,the final R = 0.0479 and wR = 0.1081.The results of X-ray crystallographic analysis revealed that C14H16ICuN2O2（1） and C14H16BrCuN2O2（2） are isostructural compounds with the dimers connected by C-H···halogen hydrogen bonds to generate a three-dimensional（3D） supramolecular network in 1 and a two-dimensional（2D） sheet structure in 2,respectively,while the mononuclear complex C28H32Cl2Cu2N4O4（3） is ionic.In 3,the [Cu（dmbp）2]＋ cations and [ClCuCl]-anions are connected by C-H···Cl hydrogen bonds to form a one-dimensional（1D） chain along the a axis.Therefore,in the three complexes,the C-H···halogen hydrogen bonds dominate their crystal structures.Additionally,The UV luminescent properties of complexes 1-3 were investigated.

Synthesis, Structure and Properties of Benzo[1,2-f:5,4-f＇]- diquinoline Derivatives： A Remarkably Strong Intramolecular C-H...O Hydrogen Bond

A series of benzo[1,2-f：5,4-f＇]diquinoline derivatives were synthesized starting from 2,7-diaminoanthracene, and their structures were determined by NMR, MS spectra and X-ray analysis. They showed a remarkably strong intramolecular C--H...O hydrogen bond, which resulted in an unexpected downfield chemical shift of the aromatic proton in CDCl3. Moreover, a significant fluorescent change of molecule lb in the presence of trifluoroacetic acid （TFA） was also observed.

[Co(meamp)(amp)Cl][ZnCl_4]体系配合物一异构体的合成、结构特征与量子化学计算

用过氧化物法合成了[Co(meamp)(amp)Cl][ZnCl4](meamp=2-[(N-甲基乙基)氨甲基]吡啶,amp=2-(氨甲基)吡啶)体系配合物的一异构体.元素分析及13C NMR,1H NMR检测表明,配合物是标题体系中的一异构体且配合物阳离子中可能具有C—H…π结构或C—H…π相互作用.

Total Synthesis of Stemarene and Betaerene Diterpenoids:Divergent Ring-Formation Strategy and Late-Stage C–H Functionalization

A unified protecting group-free approach to two stemarene and two betaerene diterpenoids through a bioinspired two-phase strategy has been developed,and three of them were obtained for the first time via chemical synthesis.Starting from a common intermediate,two distinct tetracyclic frameworks containing diastereoisomeric bridged bicycles were constructed by a divergent ring reorganization strategy.Late-stage C–H functionalization through a xanthylation-oxygenation protocol furnished the corresponding oxygenated stereocenters or oxo functionality in high regio-and diastereoselective fashion within a complex hydrocarbon system.The stereochemical puzzles in(–)-2-acetoxybetaer13(17)-ene and(+)-7-acetoxybetaer-13(17)-ene were first predicted by the comparison of density functional theory(DFT)-nuclear magnetic resonance(NMR)data with the reported data and then unambiguously addressed through the total syntheses of natural products and three diastereomers.