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Bis{4-[(3-phenylallylidene)amino]cyclohexyl}methane trichloromethane solvate  [cached]
Roberto Menzel,Angela G?bel,Helmar G?rls,Wolfgang Imhof
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808037380
Abstract: The title compound, C31H38N2, was prepared from bis(4-aminocyclohexyl)methane and two equivalents of cinnamaldehyde. The cyclohexyl groups each show a chair conformation and the α,β-unsaturated imine side chains are all-trans configured. Two molecules of the title compound as well as two trichloromethane solvent molecules are present in the asymmetric unit. The solvent molecules interact with the diimines via weak C—H...N hydrogen bonds.
Bupropion hydrobromide propanol hemisolvate  [cached]
Min Liu,Xiu-Rong Hu,Jian-Ming Gu,Gu-Ping Tang
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811037093
Abstract: The title compound {systematic name: N-[1-(3-chlorophenyl)-1-oxopropan-2-yl]-tert-butanaminium bromide propanol hemisolvate}, C13H19ClNO+·Br ·0.5C3H8O, crystallizes with two independent bupropion hydrobromide ion pairs and a solvent 1-propanol molecule in the asymmetric unit. In both molecules, the expected proton transfer from HBr to the amino group of the bupropion molecule is observed, and intra- and intermolecular N—H...Br hydrogen-bond interactions are formed. These interactions link the molecules into hydrogen-bond dimers. The side chains of the two cations have slightly different orientations. The 1-propanol solvent molecule is linked to a bromide ion by an O—H...Br hydrogen bond.
Tetrapyrazineplatinum(II) bis(tetrafluoroborate) acetonitrile hemisolvate  [cached]
Paul J. Derry,Xiaoping Wang,Bradley W. Smucker
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808033679
Abstract: The improved synthesis and characterization of tetrapyrazineplatinum(II) bis(tetrafluoroborate) acetonitrile hemisolvate, [Pt(C4H4N2)4](BF4)2·0.5CH3CN, is reported. The unit cell contains a half equivalent of an acetonitrile solvent molecule per tetrapyrazineplatinum(II) ion. The coordination geometry of the PtII ion is almost square-planar, with the Pt atom residing on an inversion center. The BF4 counter-anion, located at a general position, has an idealized tetrahedral geometry and an acetonitrile solvent molecule, the methyl group of which is disordered over two equal positions, sits on a twofold rotation axis.
Dichloridobis(2-methoxydibenzo[c,e][1,2]oxaphosphorine-κP)platinum(II) trichloromethane solvate  [cached]
Tamás Holczbauer,György Keglevich,Andrea Kerényi,Mátyás Czugler
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809006643
Abstract: The title compound, [PtCl2(C13H11O2P)2]·CHCl3, has a rare PtCl2 bridging of two dibenzooxaphosphorine ligands through the metal atom. The PtII ion is in a slightly distorted square-planar environment. The trichloromethane solvent molecule shows rotational disorder (major occupancy is 0.75) and is placed near to the inversion centre at (1/2, 1/2, 0) in channels parallel to the a axis. The solvent molecule is linked to the complex molecule via intermolecular bifurcated C—H...Cl and C—H...O hydrogen bonds. The crystal structure is further stabilized by π–π interactions involving the benzene rings, with a centroid–centroid distance of 3.658 (8) .
4–甲基–2,3,5,6–四氟苯甲醇的合成  [PDF]
何明阳,陈圣春,谢英梅,陈群
化工进展 , 2010,
Abstract: 以2,3,5,6–四氟对苯二甲醇为起始原料,经氯化、常压催化氢解制得4–甲基–2,3,5,6–四氟苯甲醇。研究表明,在甲苯中用盐酸氯化时,温度为100~105℃、反应6h、盐酸与2,3,5,6–四氟对苯二甲醇用量物质的量比为1.4,4–甲基–2,3,5,6–四氟苯甲醇产率为96.4%;在甲醇溶剂中以Pd/C为催化剂,温度为50℃、4–氯甲基–2,3,5,6–四氟苯甲醇与10%Pd/C与甲醇质量比为1∶0.05∶9.0,常压氢解4h,4–甲基–2,3,5,6–四氟苯甲醇产率为99%,两步反应总产率为95.4%。
Butallylonal 1,4-dioxane hemisolvate  [cached]
Thomas Gelbrich,Denise Rossi,Ulrich J. Griesser
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810038651
Abstract: The asymmetric unit of the title compound [systematic name: 5-(1-bromoprop-2-en-1-yl)-5-sec-butylpyrimidine-2,4,6-trione 1,4-dioxane hemisolvate], C11H15BrN2O3·0.5C4H8O2, contains one half-molecule of 1,4-dioxane and one molecule of butallylonal, with an almost planar barbiturate ring [largest deviation from the mean plane = 0.049 (5) ]. The centrosymmetric dioxane molecule adopts a nearly ideal chair conformation. The barbiturate molecules are linked together by an N—H...O hydrogen bond, giving a single-stranded chain. Additionally, each dioxane molecule acts as a bridge between two antiparallel strands of hydrogen-bonded barbiturate molecules via two hydrogen bonds, N—H...O(dioxane)O...H—N. Thus, a ladder structure is obtained, with the connected barbiturate molecules forming the `stiles' and the bridging dioxane molecules the `rungs'.
[6,13-Bis(2,4-dichlorobenzoyl)-5,7,12,14-tetramethyldibenzo[b,i][1,4,8,11]tetraazacyclotetradecinato- κ4N]nickel(II) acetone monosolvate  [cached]
Bo-Kun Jiang,Xuan Shen,Xin Wang,Fan Su
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812024671
Abstract: In the title complex, [Ni(C36H26Cl4N4O2)]·C3H6O, two 2,4-dichlorobenzoyl groups are grafted onto the methine groups of the NiII complex Ni(tmtaa) (H2tmtaa = 5,7,12,14-tetramethyl-4,11-dihydrodibenzo[b,i][1,4,8,11]tetraazacyclotetradecine). The complex has the shape of a saddle. The Ni atom is tetracoordinated by the four N atoms of the macrocycle, forming a slightly tetrahedrally distorted square-planar geometry. The metal is displaced by 0.0101 (8) from the N4 mean plane. The aromatic rings of the 2,4-dichlorobenzoyl groups form dihedral angles of 87.1 (2) and 82.1 (2)° with the N4 mean plane
2,3,5,6-四氟苯甲醇的合成有机化学  [PDF]
唐渝,屈伟月,杨骏
有机化学 , 2005,
Abstract: 经氟代、水解脱羧、酯化、还原等步骤合成了杀虫剂四氟苯菊酯的重要中间体2,3,5,6-四氟苯甲醇,改进了氟代反应的无水操作和反应条件,产物四氟对苯二甲腈纯度高达98.3%,通过加入水参与反应改进了水解反应,使水解和脱羧由两步反应变为一步,且产物为只脱一个羧基的2,3,5,6-四氟苯甲酸,收率可以高达92.5%,用相对价廉的NaBH4/I2体系还原2,3,5,6-四氟苯甲酸甲酯以52.3%的收率得到了目标产物,总收率29.6%.
A Simple and Efficient Route for Preparing 2,3,5,6-Tetraaminopyridine Hydrochloride Salt  [PDF]
Yanhong Wang,Zhen Hu,Xiangli Meng,Jiehui Jing,Yuanjun Song,Chunhua Zhang,Yudong Huang
Molecules , 2009, DOI: 10.3390/molecules14051652
Abstract: A simple and efficient route for preparing 2,3,5,6-tetraaminopyridine hydrochloride salt (TAP·3HCl·H2O) was introduced in this paper. The title compound was synthesized, as usual, in two steps (nitration and hydrogenation) with a total yield of 90%. The use of an oleum and fuming nitric acid mixture in the nitration step improved the yield and purity of the intermediate product. A highly efficient hydrogenation using a H2/Pd/C/C2H5OH system was developed. The products were characterized by TG, IR, 1H-NMR, 13C-NMR, HPLC and elemental analysis.
Aquadipicrato(tetraethylene glycol)gadolinium(III) picrate methanol hemisolvate
Eny Kusrini,Muhammad Idiris Saleh,Reza Kia,Hoong-Kun Fun
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808026147
Abstract: The asymmetric unit of the title compound [systematic name: aquabis(2,4,6-trinitrophenolato)(3,6,9-trioxaundecane-1,11-diol)gadolinium(III) 2,4,6-trinitrophenolate methanol hemisolvate], [Gd(C6H2N3O7)2(C8H18O5)(H2O)](C6H2N3O7)·0.5CH4O, contains two crystallographically independent GdIII complex cations with two uncoordinated picrate anions and one methanol molecule. Each GdIII atom has nine coordination sites occupied by five O atoms of tetraethylene glycol as a pentadentate ligand, one O atom of a water molecule and three O atoms of the two picrate anions as bidentate and monodentate ligands. The geometry is distorted tricapped trigonal prismatic. The mean planes of the two coordinated mono- and bidentate picrate ligands to the GdIII center are almost perpendicular to each other, as indicated by the dihedral angles of 89.92 (8) and 86.60 (8)° in the two complex cations. The ions are arranged in a two-dimensional network parallel to the ac plane. Short O...O and N...O contacts between the nitro groups, intramolecular C—H...O hydrogen bonds, intermolecular O—H...O, O—H...N and C—H...O hydrogen bonds, and two π–π interactions between benzene rings [centroid–centroid distances = 3.8073 (10)–3.9831 (10) ] are observed. The methanol solvent molecule is disordered over two positions, with site-occupancy factors of ca 0.6 and 0.4.
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