Chemical Constituents of Selaginella moellendorffii

Chemistry of Natural Compounds -     

Synthesis of 2-Arylquinazolin-4(3H)-one Derivatives Catalyzed by Iodine in [bmim+][ ]

Controlling selectivity of the reactions of aromatic aldehydes and 2-aminobenzamide in ionic liquid catalyzed by iodine at either room temperature or at 80 °C under nitrogen resulted in the synthesis of (E)-Schiff bases, 2,3-dihydro-2-arylquinazolin-4(1H)-one and 2-arylquinazolin-4(3H)-one derivatives, in excellent yields.     

Green Method for the Synthesis of Benzo[f]pyrimido[4,5-b]quinoline Derivatives Catalyzed by Iodine in Aqueous Media

A convenient one-pot synthesis of benzo[f]pyrimido[4,5-b]quinoline derivatives is described via three-component reaction of benzaldehydes, naphthalen-2-amine, and barbituric acid at room temperature in aqueous media catalyzed by iodine. Compared with other methods, this three-component reaction used a green solvent, gave good yields, and was operationally simple.     

A Secondary Operator Ordering Problem for a Charged Rigid PlanarRotator in Uniform Magnetic Field

When the motion of a particle is constrained, an excess term exists using hermitian form of Cartesian momentum pi(i= 1, 2, 3) in usual kinetic energy (1/2μ)∑Pi^2, and the correct kinetic energy turns out to be (1/2μ)∑(1/fi)pifipi, where the fi are dummy factors in classical mechanics and nontrivial in quantum mechanics. In this paper the explicit form of the dummy functions f i is given for a charged rigid planar rotator in the uniform magnetic fieM.     

Crystal Structure of a 4-Methyl-phenylacetylide-bridged Pt~IICu~I_2 Heterotrinuclear Organometallic Complex

1 INTRODUCTION Over the past decades, metal alkynyl complexes have attracted more and more attention due to their potential applications in conducting polymers, lumi- nescent materials and supramolecular chemis- try[1～10]. Compared to the rapid growth o…     

Synthesis and Crystal Structure of 7-Amino-2,3,4,5-tetrahydro- 1,3-dimethyl- 5-（2-nitrophenyl）-2,4-dioxo-lH-pyrano[2,3- d]pyrimidine-6-carbonitrile DMF Solvate

The title compound 7-amino-2,3,4,5-tetrahydro-1,3-dimethyl-5-（2-nitrophenyl）- 2,4- dioxo-1H-pyrano[2,3-d] pyrirnidine-6-carbonitrile DMF solvate 1 （C19H20N6O6, Mr = 428.41） was synthesized and crystallized. The crystal belongs to the monoclinic system, space group P2 1/c with a = 11.383（2）, b = 13.372（2）, c = 13.673（2）A, β = 97.380（4）°, Z = 4, V = 2063.8（6）A^3, Dc = 1.379 g/cm^3,μ（MoKα） = 0.105 mm^-1, F（000） = 896, the final R = 0.0738 and wR = 0.1647 for 2964 observed reflections （I〉 2σ（I））. X-ray analysis reveals that the new pyran ring is coplanar, which is obviously different from those of other similar compounds. In addition, the unclassical hydrogen bonds of C-H…O and C-H…N are presented in the crystals except for the normal hydrogen bonds of N-H…O.     

新型PES微孔材料的制备及性能研究

合成了新型双烯丙基聚醚砜(PES), 采用超临界CO2作为物理发泡试剂制备微孔材料, 研究了不同发泡温度、饱和压力、发泡时间和放气时间等因素对微孔形貌的影响. 结果表明, 发泡温度在110~170 ℃之间, 随着温度的升高, 泡孔直径增加, 泡孔密度在140 ℃达到一个最大值; 随着饱和压力的升高, 泡孔直径减小, 泡孔密度增大; 发泡时间和放气时间对微孔直径和密度影响不大; 研究了在不同辐照剂量下微孔材料的交联性能, 结果表明, 在600 kGy辐照剂量以下, 交联效果不明显, 在800 kGy以上, 随着辐照剂量的增大, 凝胶含量增加, 辐照后的样品在265 ℃热处理10 min, 仍能保持完好的微孔结构.     

Synthesis, structure, and reactivity of Group 4 metallacycles incorporating a Me2C-linked cyclopentadienyl-carboranyl ligand

Group 4 metallacycles [eta5:sigma-Me2C(C5H4)(C2B10H10)]Ti[eta2-N(Me)CH2CH2N(Me)] (1a), [eta5:sigma-Me2C(C5H4)(C2B10H10)]Zr[eta2-N(Me)CH2CH2N(Me)](HNMe2) (1b) and [eta5:sigma-Me2C(C5H4)(C2B10H10)]M[eta2-N(Me)CH2CH2CH2N(Me)] (M = Ti (2a), Zr (2b), Hf (2c)) were synthesized by reaction of [eta5:sigma-Me2C(C5H4)(C2B10H10)]M(NMe2)(2) (M = Ti, Zr, Hf) with MeNH(CH2)(n)NHMe (n = 2, 3). These metal complexes reacted with unsaturated molecules such as 2,6-Me2C6H3NC, PhNCO and PhCN to give exclusively M-N bond insertion products. The M-C(cage) bond remained intact. Such a preference of M-N over M-C(cage) insertion is suggested to most likely be governed by steric factors, and the mobility of the migratory groups plays no obvious role in the reactions. This work also shows that the insertion of unsaturated molecules into the metallacycles is a useful and effective method for the construction of very large ring systems.