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1.
Daniela Giardina‐Papa Francesco Paolo Intini Giovanni Natile Concetta Pacifico 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(11):m300-m302
The title compound, [PtCl(C3H7NO)2(C18H15P)]Cl·H2O or trans‐[PtCl{Z‐HN=C(Me)OMe}2(PPh3)]Cl·H2O, crystallizes from an acetone solution of isomeric trans‐[PtCl{E‐HN=C(Me)OMe}2(PPh3)]Cl. The two HN=C(Me)OMe ligands show typical π‐bond delocalization over the N—C—O group [Cini, Caputo, Intini & Natile (1995). Inorg. Chem. 34 , 1130–1137] and have the unprecedented Z–anti configuration. The relative orientation of the imino ether ligands is head‐to‐tail. 相似文献
2.
Synthesis and Characterization of a Gold Vinylidene Complex Lacking π‐Conjugated Heteroatoms
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Robert J. Harris Prof. Ross A. Widenhoefer 《Angewandte Chemie (International ed. in English)》2015,54(23):6867-6869
Hydride abstraction from the gold (disilyl)ethylacetylide complex [( P )Au{η1‐C?CSi(Me)2CH2CH2SiMe2H}] ( P =P(tBu)2o‐biphenyl) with triphenylcarbenium tetrakis(pentafluorophenyl)borate at ?20 °C formed the cationic gold (β,β‐disilyl)vinylidene complex [( P )Au?C?CSi(Me)2CH2CH2Si (Me)2]+B(C6F5)4? with ≥90 % selectivity. 29Si NMR analysis of this complex pointed to delocalization of positive charge onto both the β‐silyl groups and the ( P )Au fragment. The C1 and C2 carbon atoms of the vinylidene complex underwent facile interconversion (ΔG≠=9.7 kcal mol?1), presumably via the gold π‐disilacyclohexyne intermediate [( P )Au{η2‐C?CSi(Me)2CH2CH2Si (Me)2}]+B(C6F5)4?. 相似文献
3.
Dirk Steinborn Tobias Hoffmann Michael Gerisch Clemens Bruhn Harry Schmidt Karsten Nordhoff Julian A. Davies Kristin Kirschbaum Ingo Jolk 《无机化学与普通化学杂志》2000,626(3):661-666
The platina‐β‐diketones [Pt2{(COR)2H}2(μ‐Cl)2] ( 1 , R = Me a , Et b ) react with phosphines L in a molar ratio of 1 : 4 through cleavage of acetaldehyde to give acylplatinum(II) complexes trans‐[Pt(COR)Cl(L)2] ( 2 ) (R/L = Me/P(p‐FC6H4)3 a , Me/P(p‐CH2=CHC6H4)Ph2 b , Me/P(n‐Bu)3 c , Et/P(p‐MeOC6H4)3 d ). 1 a reacts with Ph2As(CH2)2PPh2 (dadpe) in a molar ratio of 1 : 2 through cleavage of acetaldehyde yielding [Pt(COMe)Cl(dadpe)] ( 3 a ) (configuration index: SP‐4‐4) and [Pt(COMe)Cl(dadpe)] (configuration index: SP‐4‐2) ( 3 b ) in a ratio of about 9 : 1. All acyl complexes were characterized by 1H, 13C and 31P NMR spectroscopy. The molecular structures of 2 a and 3 a were determined by single‐crystal X‐ray diffraction. The geometries at the platinum centers are close to square planar. In both complexes the plane of the acyl ligand is nearly perpendicular to the plane of the complex (88(2)° 2 a , 81.2(5)° 3 a ). 相似文献
4.
《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(2):420-428
Four novel organotin complexes of two types—[R2Sn(o‐SC6H4CO2)]6 (R=Me, 1 ?H2O; nBu, 2 ) and {[R2Sn(m‐CO2C6H4S)R2Sn(m‐SC6H4CO2)SnR2]O}2 (R=Me, 3 ; nBu, 4 )—have been prepared by treatment of o‐ or m‐mercaptobenzoic acid and the corresponding R2SnCl2 (R=Me, nBu) with sodium ethoxide in ethanol (95 %). All the complexes were characterized by elemental analysis, FT‐IR and NMR (1H, 13C, 119Sn) spectroscopy, TGA, and X‐ray crystallography diffraction analysis. The molecular structure analyses reveal that both 1 and 2 are hexanuclear macrocycles with hydrophobic “pseudo‐cage” structures, while 3 and 4 are hexanuclear macrocycles with double‐cavity structures. Furthermore, the supramolecular structure analyses show that looser and more intriguing supramolecular infrastructures were also found in complexes 1 – 4 , which exist either as one‐dimensional chains of rings or as two‐dimensional networks assembled from the organometallic subunits through intermolecular C? H???S weak hydrogen bonds (WHBs) and π–π interactions. 相似文献
5.
Ana María Atria Maria Teresa Garland Ricardo Baggio 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(7):m185-m188
The title ionic compound, (C7H8N3)2[Ho2(C4H5O2)8], is constructed from two almost identical independent centrosymmetric anionic dimers balanced by two independent 2‐amino‐1H‐benzimidazol‐3‐ium (Habim+) cations. The asymmetric part of each dimer is made up of one HoIII cation and four crotonate (crot or but‐2‐enoate) anions, two of them acting in a simple η2‐chelating mode and the remaining two acting in two different μ2:η2 fashions, viz. purely bridging and bridging–chelating. Symmetry‐related HoIII cations are linked by two Ho—O—Ho and two Ho—O—C—O—Ho bridges which lead to rather short intracationic Ho...Ho distances [3.8418 (3) and 3.8246 (3) Å]. In addition to the obvious Coulombic interactions linking the cations and anions, the isolated [Ho2(crot)8]2− and Habim+ ions are linked by a number of N—H...O hydrogen bonds, in which all N—H groups of the cation are involved as donors and all (simple chelating) crot O atoms are involved as acceptors. These interactions result in compact two‐dimensional structures parallel to (110), which are linked to each other by weaker π–π contacts between Habim+ benzene groups. 相似文献
6.
Elena V. Panteleeva Vitalij D. Shteingarts Joseph Grobe Bernt Krebs Michael U. Triller Helmut Rabeneck 《无机化学与普通化学杂志》2003,629(1):71-82
A systematic study of the direction of nucleophilic attack of the nucleophiles Me3MEMe2 (M = Si, Sn; E = P, As), NaOMe, LiR (R = Me, nBu, Ph) and PhMgBr on 5, 6, 7, 8‐tetrafluoroquinoline ( 1 ), 6‐CF3‐5, 7, 8‐trifluoroquinoline ( 2 ) and 5, 7, 8‐trifluoroquinoline ( 3 ) was performed with the aim to develop synthetic routes to specific functional derivatives and to gain a deeper insight into the mechanisms governing the regioselectivity. With the fairly “soft” nucleophiles Me3MEMe2 in general mixtures of 7‐Me2EC‐(main product) and 6‐Me2EC‐derivatives (side product) are formed (Schemes 1, 2, 4). Sulfuration of the isomer mixtures with E = P yields mixtures of the corresponding thiophosphano derivatives. The observed regioselectivity is explained by a concerted action of two factors: (i) The influence of the heteroatom N on the stabilization of the σ‐complex type transition states and (ii) the collective effect of four fluorine substituents favouring 6‐ and 7‐substitution. — The reaction of 1 with sodium methoxide (Scheme 3) was carried out to test the early conclusion on the exclusive formation of 7‐methoxy‐5, 6, 8‐trifluoroquinoline ( 14 ) [2], made on the basis of a GC‐analysis. For that purpose the molar ratio 1 : MeO— was varied from 1 : 1.25 over 1 : 1 to 1 : 0.5. — In the reactions of the quinoline precursors 1 — 3 with the organometallic reagents LiR (R = Me, nBu, Ph) and PhMgBr (Scheme 5) products of the nucleophile‐addition at position 2 were obtained in high yields, which with hydrochloric acid led to 2‐R‐1, 2‐dihydro‐5, 6, 7, 8‐tetrafluoroquinolines. In contact with air or by reaction with MnO2, oxidation to aromatic 2‐R‐5, 6, 7, 8‐tetrafluoroquinolines occurred. To rationalize the observed differences between the “soft” Me3MEMe2 and the “hard” carbon‐centred nucleophiles, two different hypothetic mechanisms are discussed. Since most of the compounds have been obtained in reaction mixtures, the assignment to structural formulae is mainly based on GCMS and CMS analyses together with 1H‐, 19F‐ and 31P NMR data and comparison with literature information and with spectra registered for individual compounds. In addition, the molecular structures of the representatives 6 , 20 and 29 , determined by X‐ray analyses, prove the structural formulae deduced from the spectra of products. 相似文献
7.
Diimido, Imido Oxo, Dioxo, and Imido Alkylidene Halfsandwich Compounds via Selective Hydrolysis and α—H Abstraction in Molybdenum(VI) and Tungsten(VI) Organyl Complexes Organometal imides [(η5‐C5R5)M(NR′)2Ph] (M = Mo, W, R = H, Me, R′ = Mes, tBu) 4 — 8 can be prepared by reaction of halfsandwich complexes [(η5‐C5R5)M(NR′)2Cl] with phenyl lithium in good yields. Starting from phenyl complexes 4 — 8 as well as from previously described methyl compounds [(η5‐C5Me5)M(NtBu)2Me] (M = Mo, W), reactions with aqueous HCl lead to imido(oxo) methyl and phenyl complexes [(η5‐C5Me5)M(NtBu)(O)(R)] M = Mo, R = Me ( 9 ), Ph ( 10 ); M = W, R = Ph ( 11 ) and dioxo complexes [(η5‐C5Me5)M(O)2(CH3)] M = Mo ( 12 ), M = W ( 13 ). Hydrolysis of organometal imides with conservation of M‐C σ and π bonds is in fact an attractive synthetic alternative for the synthesis of organometal oxides with respect to known strategies based on the oxidative decarbonylation of low valent alkyl CO and NO complexes. In a similar manner, protolysis of [(η5‐C5H5)W(NtBu)2(CH3)] and [(η5‐C5Me5)Mo(NtBu)2(CH3)] by HCl gas leads to [(η5‐C5H5)W(NtBu)Cl2(CH3)] 14 und [(η5‐C5Me5)Mo(NtBu)Cl2(CH3)] 15 with conservation of the M‐C bonds. The inert character of the relatively non‐polar M‐C σ bonds with respect to protolysis offers a strategy for the synthesis of methyl chloro complexes not accessible by partial methylation of [(η5‐C5R5)M(NR′)Cl3] with MeLi. As pure substances only trimethyl compounds [(η5‐C5R5)M(NtBu)(CH3)3] 16 ‐ 18 , M = Mo, W, R = H, Me, are isolated. Imido(benzylidene) complexes [(η5‐C5Me5)M(NtBu)(CHPh)(CH2Ph)] M = Mo ( 19 ), W ( 20 ) are generated by alkylation of [(η5‐C5Me5)M(NtBu)Cl3] with PhCH2MgCl via α‐H abstraction. Based on nmr data a trend of decreasing donor capability of the ligands [NtBu]2— > [O]2— > [CHR]2— ? 2 [CH3]— > 2 [Cl]— emerges. 相似文献
8.
Synthesis and X‐ray Crystal Structures of Zinc Dichloride Complexes Supported by a β‐Diimine Ligand
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Christoph Scheiper Dominik Naglav Dieter Bläser Christoph Wölper Stephan Schulz 《无机化学与普通化学杂志》2015,641(5):871-875
β‐Diimine zinc dichloride complexes [CH2{C(Me)NAr}2]ZnCl2 [Ar = Mes ( 1 ), Dipp ( 2 )] were obtained from the reactions of ZnCl2 with the corresponding β‐iminoamines [ArN(H)C(Me)CHC(Me)NAr]. Complexes 1 and 2 were characterized by multinuclear NMR (1H, 13C) and IR spectroscopy, elemental analyses as well as by single‐crystal X‐ray diffraction. The energy differences between the enamine‐imine tautomers of the β‐iminoamines were quantified by quantum chemical calculations. 相似文献
9.
Qian‐Jun Deng Ming‐Hua Zeng Hong Liang Ke‐Long Huang 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(9):m389-m391
The title compound, [Cd(C3H6NO5P)(H2O)2]n, is a three‐dimensional polymeric complex. The asymmetric unit contains one Cd atom, one N‐(phosphonomethyl)glycine zwitterion [(O−)2OPCH2NH2+CH2COO−] and two water molecules. The coordination geometry is a distorted CdO6 octahedron. Each N‐(phosphonomethyl)glycine ligand bridges four adjacent water‐coordinated Cd cations through three phosphonate O atoms and one carboxylate O atom, like a regular PO43− group in zeolite‐type frameworks. One‐dimensional zigzag (–O—P—C—N—C—C—O—Cd–)n chains along the [101] direction are linked to one another via Cd—O—P bridges and form a three‐dimensional network motif with three types of channel systems. The variety of O—H⋯O and N—H⋯O hydrogen bonds is likely to be responsible for stabilizing the three‐dimensional network structure and preventing guest molecules from entering into the channels. 相似文献
10.
Reactions of Pentafulvene Complexes of Titanium with Nitriles and iso‐Nitriles — Synthesis and Isomerizations of σ, π‐Chelat Complexes with Cp∼N‐Ligands The reactions of fulvene complexes Cp*Ti{η6—C5H4=C(R)(R')}Cl (R = H, R' = tBu ( 1 ); R = Me, R' = iPr ( 4 )) with nitriles and iso‐nitriles, leading to σ, π‐chelat complexes with Cp∼N‐ligands, have been examined and the formed products characterized. Whereas in the reactions of 1 and 4 , respectively, with nitriles a 1, 2‐mono‐insertion of the CN‐group in the Ti—C(R)(R') (Fv) bond is observed, the reaction with iso‐nitrils leads to the insertion of two molecules iso‐nitrile. The nitrile insertion product of 1 is characterized by an imine‐enamine tautomerization. Whereas the primary built meta stable imine species ( 3 ) was only identified by NMR measurements in solution, the enamine tautomer ( 2 ) crystallized from n‐hexane, so that the crystal structure could be determined. The primary formed iminoacyl complex ( 7 ) rearranges due to the electrophilicity of the titanium centre and builds a Ti—N bond with significant N(pπ) → Ti(dπ) bonding character. 相似文献
11.
Dr. Tetsuya Fukuda Dr. Hisako Hashimoto Prof. Dr. Shigeyoshi Sakaki Prof. Dr. Hiromi Tobita 《Angewandte Chemie (International ed. in English)》2016,55(1):188-192
Treatment of pyridine‐stabilized silylene complexes [(η5‐C5Me4R)(CO)2(H)W?SiH(py)(Tsi)] (R=Me, Et; py=pyridine; Tsi=C(SiMe3)3) with an N‐heterocyclic carbene MeIiPr (1,3‐diisopropyl‐4,5‐dimethylimidazol‐2‐ylidene) caused deprotonation to afford anionic silylene complexes [(η5‐C5Me4R)(CO)2W?SiH(Tsi)][HMeIiPr] (R=Me ( 1‐Me ); R=Et ( 1‐Et )). Subsequent oxidation of 1‐Me and 1‐Et with pyridine‐N‐oxide (1 equiv) gave anionic η2‐silaaldehydetungsten complexes [(η5‐C5Me4R)(CO)2W{η2‐O?SiH(Tsi)}][HMeIiPr] (R=Me ( 2‐Me ); R=Et ( 2‐Et )). The formation of an unprecedented W‐Si‐O three‐membered ring was confirmed by X‐ray crystal structure analysis. 相似文献
12.
Li‐Feng Tan Fang Wang Hui Chao Sheng Zhang Jun‐Jie Fei Liang‐Nian Ji 《Helvetica chimica acta》2008,91(7):1251-1260
A novel polypyridine ligand, dipyrido[3,2‐a:2′,3′‐c]phenazine‐11‐carboxylic acid methyl ester (=dppz‐11‐CO2Me), and its ruthenium(II) complex, [Ru(bpy)2(dppz‐11‐CO2Me)]2+ ( 1 ), were synthesized and characterized. The binding properties of this complex to calf‐thymus DNA (CT‐DNA) were investigated by different spectrophotometric methods and viscosity measurements. The results suggest that the complex binds to DNA in an intercalative mode and serves as a molecular ‘light switch’ for DNA. When irradiated at 365 nm, the complex 1 promoted the photocleavage of plasmid pBR‐322 DNA. 相似文献
13.
Regiodirected Synthesis and Stereochemistry of 2,4,8‐Trialkyl‐3‐thia‐1,5‐diazabicyclo[3.2.1]octanes and α,ω‐Bis(2,4,6‐trialkyl‐1,3,5‐dithiazinane‐5‐yl)alkanes
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Vnira R. Akhmetova Ruslan A. Vagapov Tat'yana V. Tyumkina Guzel R. Khabibullina Zoya A. Starikova Alexander H. Lobov Yuliya V. Nelyubina Raikhana V. Kunakova Usein M. Dzhemilev 《Journal of heterocyclic chemistry》2015,52(4):1037-1045
2,4,8‐Trialkyl‐3‐thia‐1,5‐diazabicyclo[3.2.1]octanes have been obtained by the regioselective and stereoselective cyclocondensation of 1,2‐ethanediamine with aldehydes RCHO (R═Me, Et, Prn, Bun, Pentn) and H2S at molar ratio 1:3:2 at 0°C. The increase in molar ratio of thiomethylation mixture RCHO–H2S (6:4) at 40°C resulted in selective formation of bis‐(2,4,6‐trialkyl‐1,3,5‐dithiazinane‐5‐yl)ethanes. Cyclothiomethylation of aliphatic α,ω‐diamines with aldehydes RCHO (R═Me, Et) and H2S at molar ratio 1:6:4 and at 40°С led to α,ω‐bis(2,4,6‐trialkyl‐1,3,5‐dithiazinane‐5‐yl)alkanes. Stereochemistry of 2,4,8‐trialkyl‐3‐thia‐1,5‐diazabicyclo[3.2.1]octanes have been determined by means of 1H and 13С NMR spectroscopy and further supported by DFT calculations at the B3LYP/6‐31G(d,p) level. The structure of α,ω‐bis(2,4,6‐trialkyl‐1,3,5‐dithiazinane‐5‐yl)alkanes was confirmed by single‐crystal X‐ray diffraction study. 相似文献
14.
Mariya Edeleva Sylvain R. A. Marque Kuanish Kabytaev Yohann Guillaneuf Didier Gigmes Elena Bagryanskaya 《Journal of polymer science. Part A, Polymer chemistry》2013,51(6):1323-1336
Thermal decomposition of four tertiary N‐(2‐methylpropyl)‐N‐(1‐diethylphosphono‐2,2‐dimethylpropyl)‐N‐oxyl (SG1)‐based alkoxyamines (SG1‐C(Me)2‐C(O)‐OR, R = Me, tBu, Et, H) has been studied at different experimental conditions using 1H and 31P NMR spectroscopies. This experiment represents the initiating step of methyl methacrylate polymerization. It has been shown that H‐transfer reaction occurs during the decomposition of three alkoxyamines in highly degassed solution, whereas no products of H‐transfer are detected during decomposition of SG1‐MAMA alkoxyamine. The value of the rate constant of H‐transfer for alkoxyamines 1 (SG1‐C(Me)2‐C(O)‐OMe) and 2 ( SG1‐C(Me)2‐C(O)‐OtBu) has been estimated as 1.7 × 103 M?1s?1. The high influence of oxygen on decomposition mechanism is found. In particular, in poorly degassed solutions, nearly quantitative formation of oxidation product has been observed, whereas at residual pressure of 10?5 mbar, the main products originate from H‐atom transfer reaction. The acidity of the reaction medium affects the decomposition mechanism suppressing the H‐atom transfer. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
15.
r‐1, c‐2, t‐3, t‐4‐1,3‐Bis[2‐(5‐R‐benzoxazolyl)]‐2,4‐di(4‐R'‐phenyl)cyclobutane (IIa: R=R' = H; IIb: R=Me, R'= H; IIc: R = Me, R' = OMe) was synthesized with high stereo‐selectivity by the photodimerization of trans‐l‐[2‐(5‐R‐benzoxazolyl)]‐2‐(4‐R'‐phenyl) ethene (Ia: R=R' = H; Ib: R = Me, R' = H; Ic: R = Me, R' = OMe) in sulfuric acid. The structures of IIa–IIc were identified by elemental analysis, IR, UV, 1H NMR, 13C NMR and MS. The molecular and crystal structure of IIc has been determined by X‐ray diffraction method. The crystal of IIc (C34H30N2O4. 0.5C2OH) is monoclinic, space group P21/n with cell dimensions of a = 1.5416(3), b =0.5625(1), c = 1.7875(4) nm, β = 91.56 (3)°, V= 1.550(1) nm3, Z = 2. The structure shows that the molecule of IIc is centrosymmetric, which indicates that the dimerization process is a head‐to‐tail fashion. The selectivity of the photodimerization of Ia–Ic has been enhanced by using acidic solvent and the reaction speed would be decreased when electron donating group was introduced in the 4‐position of the phenyl group. That the photodimerization is not affected by the presence of oxygen as well as its high stereo‐selectivity demonstrated that the reaction proceeded through an excited singlet state. It was also found that under irradiation of short wavelength UV, these dimers underwent photolysis completely to reproduce its trans‐monomers, and then the new formed species changed into their cis‐isomers through trans‐cis isomerization. 相似文献
16.
Daniel E. Vicentes Ricaurte Rodríguez Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(7):770-773
The molecules of 3‐amino‐4‐anilino‐1H‐isochromen‐1‐one, C15H12N2O2, (I), and 3‐amino‐4‐[methyl(phenyl)amino]‐1H‐isochromen‐1‐one, C16H14N2O2, (II), adopt very similar conformations, with the substituted amino group PhNR, where R = H in (I) and R = Me in (II), almost orthogonal to the adjacent heterocyclic ring. The molecules of (I) are linked into cyclic centrosymmetric dimers by pairs of N—H...O hydrogen bonds, while those of (II) are linked into complex sheets by a combination of one three‐centre N—H...(O)2 hydrogen bond, one two‐centre C—H...O hydrogen bond and two C—H...π(arene) hydrogen bonds. 相似文献
17.
Shan Gao Xian‐Fa Zhang Li‐Hua Huo Hui Zhao 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(3):m133-m135
In the title complex, [Mn(C5H4NO)2(C5H5NO)2]n or [Mn(μ‐3‐PyO)2(3‐PyOH)2]n (3‐PyO− is the pyridin‐3‐olate anion and 3‐PyOH is pyridin‐3‐ol), the MnII atom lies on an inversion centre and has octahedral geometry, defined by two N atoms and two deprotonated exocyclic O atoms of symmetry‐related pyridin‐3‐olate ligands [Mn—N = 2.3559 (14) Å and Mn—O = 2.1703 (11) Å], as well as two N atoms of terminal 3‐PyOH ligands [Mn—N = 2.3482 (13) Å]. The MnII atoms are bridged by the deprotonated pyridin‐3‐olate anion into a layer structure, generating sheets in the (01) plane. These sheets are linked by O—H⋯O hydrogen bonds. There are also π–π and C—H⋯π interactions in the crystal structure. 相似文献
18.
Edison Castro Henry Insuasty Braulio Insuasty Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(11):1064-1068
The title compound, C18H18N4OS2, was prepared by reaction of S,S‐diethyl 2‐thenoylimidodithiocarbonate with 5‐amino‐3‐(4‐methylphenyl)‐1H‐pyrazole using microwave irradiation under solvent‐free conditions. In the molecule, the thiophene unit is disordered over two sets of atomic sites, with occupancies of 0.814 (4) and 0.186 (4), and the bonded distances provide evidence for polarization in the acylthiourea fragment and for aromatic type delocalization in the pyrazole ring. An intramolecular N—H...O hydrogen bond is present, forming an S(6) motif, and molecules are linked by N—H...O and N—H...N hydrogen bonds to form a ribbon in which centrosymmetric R22(4) rings, built from N—H...O hydrogen bonds and flanked by inversion‐related pairs of S(6) rings, alternate with centrosymmetric R22(6) rings built from N—H...N hydrogen bonds. 相似文献
19.
Alexander Gutirrez Braulio Insuasty Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(1):o10-o12
The title compound, C16H14FNOS, crystallizes with Z′ = 2 in the space group P21/c. In one of the two independent molecules, the heterocyclic ring is effectively planar, but in the other molecule this ring adopts an envelope conformation. The molecules are weakly linked by two C—H...O hydrogen bonds to form C22(14) chains. Comparisons are made with some symmetrically substituted 2‐aryl‐3‐benzyl‐1,3‐thiazolidin‐4‐ones. 相似文献
20.
Sofiane Mekki Valrie Rolland Salima Bellahouel Arie van der Lee Marc Rolland 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(8):o301-o305
Two concomitant polymorphs, (I) and (II), of a β‐benzyl‐β‐hydroxyaspartate analogue [systematic name: dibenzyl 2‐benzyl‐2‐hydroxy‐3‐(4‐methylphenylsulfonamido)succinate], C32H31NO7S, crystallize from a mixture of ethyl acetate and cyclohexane at ambient temperature. The structure of (I) has triclinic (P) symmetry and that of (II) monoclinic (P21/c) symmetry. Both crystal structures are made up of a stacking of homochiral racemic dimers (2S,3S and 2R,3R) which are internally connected by a similar R22(9) hydrogen‐bonding pattern consisting of intermolecular N—H...O and O—H...O hydrogen bonds. The centroid of the racemic dimer lies on an inversion centre. The main structural difference between the two polymorphs is the conformational orientation of two of the four aromatic rings present in the molecule. Polymorph (II) is found to be twinned by reticular merohedry with twin index 3 and twin fractions 0.854 (1) and 0.146 (1). 相似文献