取代苯酚中共振增强的分子内氢键

根据晶体结构资料，计算了59个邻位取代苯酚中分子内氢键的几何．在STO－3G水平上计算了一些分子中原子部分电荷．结果表明，酚基氧与苯环上碳之间的键长，酚基上氢原子的部分电荷，酚基所在位置处的苯环环内角与取代苯酚的酸常数pKa均有近似线性关系，当邻位上存在硝基或羰基时，内氢键由于共振而得到显著的增强，据此可说明这一类酚的显著酸性     

一种新型双缩合螺吡喃的合成、表征及晶体结构

以过量吲哚啉和5-硝基水杨醛为原料合成了4-(2-亚甲基-1-乙基-3,3-二甲基吲哚啉-2'-基)-6-硝基-1'-乙基-3',3'-二甲基-螺[3,4-二氢-2H-l-苯并吡喃-2,2'-吲哚啉],通过核磁共振、红外光谱、元素分析对其结构进行了表征.同时利用X单晶衍射仪测定了该化合物的结构,结果表明:晶体属单斜晶系,空间群P21/n,a=1.2476(3)nm,b=1.1939(2)nm,c=2.0317(4)nm,α=90°,β=107.45(3)°,γ=90°,Dc=1.205g/cm3,μ=0.077mm-1,F(000)=1120,V=2.8871(10)nm3,Z=4.     

Molecular and Crystal Structure of 1-(4-Chlorophenyl)- 3- (4-Nitrophenyl)- 1-Triazene

１　ＩＮＴＲＯＤＵＣＴＩＯＮＩｔｈａｓｂｅｅｎｒｅｐｏｒｔｅｄｔｈａｔ１,３－ｄｉｐｈｅｎｙｌｔｒｉａｚｅｎｅｓｈｏｗｓａｕｔｉｔｕｍｏｒａｃｔｉｖｉｔｙｃｏｍｐａ－ｒａｂｌｅｔｏｔｈａｔｏｆ３,３－ｄｉｍｅｔｈｙｌ－１－ｄｉａｒｙｌｔｒｉａｚｅｎｅｓ．１,３－ｄｉａｒｙｌｔｒｉａｚｅｎｅｓｃａｎａｃｔａｓｐｒｏ－ｄｒｕｇｓ,ｏｒｃａｒｒｉｅｒｏｆｄｉａｚｏｎｉｕｍｃｏｍｐｏｕｎｄｓ,ｓｉｎｃｅｔｈｅｙｕｎｄｅｒｇｏｈｙｄｒｏｌｙｓｉｓｔｏｆｏｒｍａｒｙｌｄｉａｚｏｎｉｕｍｃｏｍｐｏｕｎｄｓ〔１…     

纳米二氧化铈的高压拉曼光谱研究

本文利用金刚石对顶砧高压技术,在0.1MPa～47.5GPa压力范围内对粒径为8nm的纳米CeO2进行了高压拉曼光谱研究。研究结果表明,常压下萤石结构的纳米CeO2(空间群Fm3m)在24.3GPa时开始发生萤石结构到PbCl2类型(空间群Pnam)的结构相变。这个相变为可逆相变,卸压至零压时样品恢复至萤石结构。     

Crystal and Molecular Structure of 4-Hydroxy-3-Methoxy-4-N-Methylstilbazonium Iodide C15H16NO2+·I-

The crystal structure of the title compound C15H16NO2+ · I-(Mr=369. 19) has been determined by single crystal X-ray diffraction analysis. The crystal belongs to tbe monoclinic system with space group P21/c, a=8. 957(1), b=21. 8117(2), c=7. 8760(10)A , β=103.94(1)°, V=1493.8(3)A3, Z=4, Dc=1. 642g cm3,μ=2. 141mm-1, F(000)=728, final R=0. 0264, and Rw=0. 0644(I＞2σ(I)) for 2938 independent reflections. The results show that in the crystal structure of the title compound the planar cations have two configurations, and these cations are anti-parallelly packed through the strong π…π interaction.     

Molecular and Crystal Structure of 1-(4-Chlorophenyl)-3-(2-nitrophenyl)-1-triazene

1　ＩＮＴＲＯＤＵＣＴＩＯＮＩｔｈａｓｂｅｅｎｒｅｐｏｒｔｅｄｔｈａｔ1,3ｄｉｐｈｅｎｙｌｔｒｉａｚｅｎｅｓｈｏｗｓａｎｔｉｔｕｍｏｕｒａｃｔｉｖｉｔｙｃｏｍｐａｒａｂｌｅｔｏｔｈａｔｏｆ3,3ｄｉｍｅｔｈｙｌ1ａｒｙｌｔｒｉａｚｅｎｅｓ.1,3Ｄｉａｒｙｌｔｒｉａｚｅｎｅｓｃａｎａｃｔａｓｐｒｏｄｒｕｇｓ,ｏｒ‘ｃａｒｒｉｅｒｓ’ｏｆｄｉａｚｏｎｉｕｍｃｏｍｐｏｕｎｄｓ,ｓｉｎｃｅｔｈｅｙｕｎｄｅｒｇｏｈｙｄｒｏｌｙｓｉｓｔｏｆｏｒｍａｒｙｌｄｉａｚｏｎｉｕｍｃｏｍｐｏｕｎｄｓ[1,2].Ａｎｄｓｏｍｅｏｎｅｈ…     

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)A,β=89.82(1)A°,V=1170.8(3)A3,Z=4,Dc=1.363 g/cm3,μ(MoKα)=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>2σ(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] throughπ…πinteractions.The C-H…O hydrogen bond (3.403 A,120.4°) laterally connects the stacks along [010] to form networks (001) which are further anti-parallelly connected by C-H…O(3.382 A,142.9°) andπ…πinteractions extending along [001].Also presented here is a brief study on the C-H…O hydrogen bonds in nitro-substituted benzyl-ideneanilines which can be classified into five types,namely,R12(5)R21(4),R22(8),R12(6),andR22(7),with the first three occurring more often.     

Cooperative C-H…O H-bonds in ''Bay Area'' and Crystal Structure of 1-(4-Methylphenyl)- 3-(4-methoxyphenyl)-2-propene-1-one

The title compound (C17H16O2, Mr = 252.30) crystallizes in the monoclinic system, space group P21/c with a = 11.5763(14), b = 11.0321(11), c = 11.5094(13) (A),β = 114.581(3)°, V= 1336.7(3) (A)3, Z = 4, Dc = 1.254 g/cm3, μ(MoKa) = 0.081 cm-1 and F(000) = 536.00. The final R and wR are 0.0527 and 0.1285, respectively for 3058 observed reflections (I ＞ 2σ(I)). In the title molecule, two phenyl rings are rotated oppositely with respect to the central part C(1)-C(2)=C(3)- C(4) (plane 3) and the dihedral angle between them is 14.8°. The phenone O(1) atom deviates from plane 3 by 0.291(A). In the crystal the molecules form H-bond chains of R21(6) and R21 (5) types similar crystals are also presented.