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1.
Luis E. Seijas Gerzon E. Delgado Asilo J. Mora Ali Bahsas Alexander Briceo 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(5):o303-o305
In the title compound, also known as N‐carbamoyl‐l ‐proline, C6H10N2O3, the pyrrolidine ring adopts a half‐chair conformation, whereas the carboxyl group and the mean plane of the ureide group form an angle of 80.1 (2)°. Molecules are joined by N—H...O and O—H...O hydrogen bonds into cyclic structures with graph‐set R22(8), forming chains in the b‐axis direction that are further connected via N—H...O hydrogen bonds into a three‐dimensional network. 相似文献
2.
Ferdinand Krner Markus Schürmann Hans Preut Wolfgang Kreiser 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):76-77
Esterification of a single diastereomer of 2‐(4‐methylenecyclohex‐2‐enyl)propanol, (II), with (1R,4S)‐(+)‐camphanic acid [(1R,4S)‐4,7,7‐trimethyl‐3‐oxo‐2‐oxabicyclo[2.2.1]heptane‐1‐carboxylic acid] leads to the crystalline title compound, C20H28O4. The relative configuration of the camphanate was determined by X‐ray diffraction analysis. The outcome clarifies the relative and absolute stereochemistry of the naturally occurring bisabolane sesquiterpenes β‐turmerone and β‐sesquiphellandrene, since we have converted (II) into both natural products via a stereospecific route. 相似文献
3.
Shar S. Al‐Shihry Anthony Linden 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(2):m40-m42
The title compound, [Fe(C5H5)(C21H21O3)], was obtained from successive Stobbe condensations between ketones and dimethyl succinate. The succinic anhydride five‐membered ring is distorted significantly from planarity, with the butadiene moiety being twisted by 49.3 (2)° from planarity and the C atoms at the succinic anhydride end of the alkene bonds showing significant pyramidalization. The cyclopentadiene rings of the ferrocenyl moiety adopt an almost eclipsed conformation. 相似文献
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Yang‐Yi Yang Lap Szeto Gang‐Feng Ouyang Zhong‐Qi Huang Wing‐Tak Wong Seik Weng Ng 《应用有机金属化学》2005,19(3):352-353
There are two types of Cd in the title compound, the six‐coordinated Cd atom in the cation is in a distorted octahedral geometry while the four‐coordinated Cd in the anion shows a distorted tetrahedral geometry. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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Vijayakumar N. Sonar Sean Parkin Peter A. Crooks 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(8):o527-o530
In the title compounds, C12H12N2O2, (I), and C17H14N2O2, (II), respectively, the indole rings are planar and the vinyl groups lie out of the indole planes, making dihedral angles of 33.48 (5) and 41.31 (8)°, respectively. In (II), the dihedral angle between the phenyl and indole ring planes is 32.06 (6)°. In both molecules, the double bond connecting the methylnitrovinyl group and the indole nucleus adopts an E configuration. Notwithstanding the differences in space group [C2/c for (I) and P212121 for (II)], the mode of packing of compounds (I) and (II) is determined by similar intermolecular N—H⋯O hydrogen‐bonding interactions, forming chains that run parallel to [101] in (I) and [001] in (II). 相似文献
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Takanori Endo Fumio Sasaki Hisashi Hara Jyunko Suzuki Shizuka Tamura Yoshikazu Nagata Tetsuro Iyoshi Atsuhiro Saigusa Taichi Nakano 《应用有机金属化学》2007,21(3):183-197
A Pd(dba)2–P(OEt)3 combination allowed the silastannation of arylacetylenes, 1‐hexyne or propargyl alcohols with tributyl(trimethylsilyl)stannane to take place at room temperature, producing (Z)‐2‐silyl‐1‐stannyl‐1‐substituted ethenes in high yields. Novel silyl(stannyl)ethenes were fully characterized by 1H‐, 13C‐, 29Si‐ and 119Sn‐NMR as well as infrared and mass analyses. Treatment of a series of (Z)‐1‐aryl‐2‐silyl‐1‐stannylethenes and (Z)‐1‐(3‐pyridyl)‐2‐silyl‐1‐stannylethene with hydrochloric acid or hydroiodic acid in the presence of tetraethylammonium chloride (TEACl) or tetrabutylammonium iodide (TBAI) led to the exclusive formation of (E)‐trimethyl(2‐arylethenyl)silanes with high stereoselectivity. A similar reaction of (Z)‐1‐(2‐anisyl)‐2‐silyl‐1‐stannylethene also produced E‐type trimethyl[2‐(2‐anisyl)ethenyl]silane, while (Z)‐trimethyl [2‐(2‐pyridyl)ethenyl]silane was produced exclusively from (Z)‐1‐(2‐pyridyl)‐2‐silyl‐1‐stannylethene. Protodestannylation of (Z)‐1‐[hydroxy(phenyl)methyl]‐2‐silyl‐1‐stannylethene with trifluoroacetic acid took place via the β‐elimination of hydroxystannane, providing trimethyl(3‐phenylpropa‐1,2‐dienyl)silane quite easily. The destannylation products were also fully characterized. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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The Cd atom in Cd(Hmmi)2I2 is five‐coordinate with a trigonal bipyramidal geometry in which the apical sites are occupied by I and O atoms. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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Paolo Sanna Antonio Carta Laura Gherardini Mohammad Esmail Rahbar Nikookar 《ChemInform》2002,33(45):221-221
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Jason Vachon Steen Brian Schougaard 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(10):m382-m384
The title compound, [Ni(C8H12BN4)(C13H18BN6)] or Bp′Tp′NiII, where Bp′ is (3,5‐dimethylpyrazol‐1‐yl)dihydro(pyrazol‐1‐yl)borate and Tp′ is bis(3,5‐dimethylpyrazol‐1‐yl)hydro(pyrazol‐1‐yl)borate, contains a divalent NiII centre bound by the chelating N atoms of the polysubstituted pyrazolylborate ligands. It is shown to lack a strong agostic B—H...Ni interaction, implying that the sixth coordination site is unoccupied in the solid state. This square‐pyramidal complex is the only known crystal structure where the NiII centre is pentacoordinated while bonded exclusively to pyrazolyl units. This is of interest with respect to electrochemical and catalytic properties. 相似文献
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Co(CH3)(PMe3)4 forms 100 % regioselectively with (2‐(2‐diphenylphosphanyl)phenyl)‐1,3‐dioxalane and 2‐diphenylphosphanyl‐pyridine, by elimination of methane, the four‐membered metallacycles Co{(C3O2HC6H3)P(C6H5)2}(PMe3)3 ( 1 ) and Co{(CNC4H3)P(C6H5)2}(PMe3)3 ( 4 ). The regioselectivity is independent of the steric requirement of the ortho substituent in the 2‐diphenylphosphanylaryl‐ligands. Oxidative addition with iodomethane transforms 1 and 4 into octahedral, diamagnetic low‐spin d6 complexes Co(CH3)I‐{(C3O2HC6H3)P(C6H5)2}(PMe3)2 ( 2 ) and Co(CH3)I‐{(CNC4H3)P(C6H5)2}(PMe3)2 ( 5 ). Under an atmosphere of carbon monoxide, insertion into the Co‐C bond results in ring expansion by forming the new assembled phosphanylbenzoyl complexes Co{(C4O3HC6H3)‐P(C6H5)2}CO(PMe3)2 ( 3 ) and Co{(OCNC4H3)P(C6H5)2}CO(PMe3)2 ( 6 ). The three different types of cobaltacycles are supported by X‐ray diffraction of 1 , 3 , 5 and 6 . 相似文献
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All Solid State Chromium(III) Selective Potentiometric Sensor Based on 2‐(1‐(2‐((3‐(2‐Hydroxyphenyl)‐1H‐pyrozol‐1‐yl)methyl)benzyl)‐1H‐pyrazol‐3‐yl)phenol
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Pankaj Kumar Sanjeev Kumar Sapna Jain Bhawna Y. Lamba Girdhar Joshi Shefali Arora 《Electroanalysis》2014,26(10):2161-2167
Highly selective all solid state electrochemical sensor based on a synthesized compound i.e. 2‐(1‐(2‐((3‐(2‐hydroxyphenyl)‐1H‐pyrozol‐1‐yl)methyl)benzyl)‐1H‐pyrazol‐3‐yl)phenol (I) as an ionophore has been prepared and investigated for the selective quantification of chromium(III) ions. The effect of various plasticizers, viz. dibutyl phosphonate (DBP), dibutyl(butyl) phosphonate (DBBP), nitrophenyl octyl ether (NPOE), tris‐(2‐ethylhexyl)phosphonate (TEP), tri‐butyl phosphonate (TBP), dioctyl phthalate (DOP), dioctyl sebacate (DOS), benzyl acetate (BA) and acetophenone (AP) along with anion excluders NaTPB (sodium tetraphenyl borate) and KClTPB (potassium(tetrakis‐4‐chlorophenyl)borate was also studied. The optimum composition of the best performing membrane contained (I):KClTPB:NPOE:PVC in the ratio 15 : 3 : 40 : 42 w/w. The sensor exhibited near Nernstian slope of 20.1±0.2 mV/decade of activity in the working concentration range of 1.2×10?7–1.0×10?1 M, and in a pH range of 3.8–4.5. The sensor exhibited a fast response time of 10 s and could be used for about 5 months without any considerable divergence in potentials. The proposed sensor showed very good selectivity over most of the common cations including Na+, Li+, K+, Cu2+, Sr2+, Ni2+, Co2+, Ba2+, Hg2+, Pb2+, Zn2+, Cs+, Mg2+, Cd2+, Al3+, Fe3+and La3+. The activity of Cr(III) ions was successfully determined in the industrial waste samples by using this sensor. 相似文献
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N. Arunadevi S. Devipriya S. Vairam 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(2):o61-o64
The title molecular salts, N2H5+·C7H5O3−·C7H6O3 and N2H5+·C11H7O3−·C11H8O3, are acid adducts containing a hydrazinium cation, one molecule of a deprotonated acid and one molecule of a neutral acid. The two compounds contain essentially identical hydrogen‐bond networks between the hydrazinium cation and the acid molecules, which define closely comparable two‐dimensional layers in the structures. The planes of the aromatic rings within both structures are approximately parallel and the layers are stacked with comparable intermolecular interactions. 相似文献
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Deepak Chopra T. P. Mohan B. Vishalakshi T. N. Guru Row 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(12):o704-o710
In the molecular structures of a series of substituted chalcones, namely (2E)‐3‐(2‐fluoro‐4‐phenoxyphenyl)‐1‐phenylprop‐2‐en‐1‐one, C21H15FO2, (I), (2E)‐3‐(2‐fluoro‐4‐phenoxyphenyl)‐1‐(4‐fluorophenyl)prop‐2‐en‐1‐one, C21H14F2O2, (II), (2E)‐1‐(4‐chlorophenyl)‐3‐(2‐fluoro‐4‐phenoxyphenyl)prop‐2‐en‐1‐one, C21H14ClFO2, (III), (2E)‐3‐(2‐fluoro‐4‐phenoxyphenyl)‐1‐(4‐methylphenyl)prop‐2‐en‐1‐one, C22H17FO2, (IV), and (2E)‐3‐(2‐fluoro‐4‐phenoxyphenyl)‐1‐(4‐methoxyphenyl)prop‐2‐en‐1‐one, C22H17FO3, (V), the configuration of the keto group with respect to the olefinic double bond is s‐cis. The molecules pack utilizing weak C—H...O and C—H...π intermolecular contacts. Identical packing motifs involving C—H...O interactions, forming both chains and dimers, along with C—H...π dimers and π–π aromatic interactions are observed in the fluoro, chloro and methyl derivatives. 相似文献
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Bjorn Olesen Marcus R. Bond 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(3):o196-o197
The analysis of the title compound, C10H15NO4, firmly establishes the configuration of the double bond as E, a stereochemistry that had been assigned tentatively by other methods. The diacetylamine and acetate substituents are approximately coplanar to one another, but approximately perpendicular to the planar ethene core. H atoms of the ethene methyl substituents are found within the ethene plane, indicating that hyperconjugation does not play an important role in stabilizing the double bond. 相似文献
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Mercuric Acetate Mediated Oxidative Cyclization of (2E, 4E)‐1‐(2‐Hydroxyphenyl)‐5‐phenylpenta‐2,4‐dien‐1‐ones: Synthesis of (Z)‐2‐((E)‐3‐Phenylallylidene)benzofuran‐3(2H)‐ones
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(2E,4E)‐1‐(2‐Hydroxyphenyl)‐5‐phenylpenta‐2,4‐dien‐1‐ones 1a , 1b , 1c , 1d , 1e on oxidative cyclization with mercuric acetate in dimethylsulphoxide have provided (Z)‐2‐((E)‐3‐phenylallylidene)benzofuran‐3(2H)‐ones 2a , 2b , 2c , 2d , 2e in good yields. 相似文献
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Yao‐Cheng Shi Su‐Hua Zhang Hong‐Jian Cheng Wei‐Ping Sun 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(9):m407-m410
The title compounds, both [Fe(C5H5)(C15H14NO2)], crystallize with Z′ = 2 in the centrosymmetric space group P. In each compound, there is an intramolecular N—H⋯O=C hydrogen bond, and pairs of intermolecular O—H⋯O=C hydrogen bonds link the molecules into chains, parallel to [10] in the 3‐hydroxy compound and parallel to [10] in the 4‐hydroxy compound. 相似文献