共查询到20条相似文献,搜索用时 15 毫秒
1.
Diana T. Patoilo Artur M. S. Silva Diana C. G. A. Pinto Augusto C. Tomé José A. S. Cavaleiro 《Journal of heterocyclic chemistry》2007,44(6):1345-1350
The Diels‐Alder reaction of 5‐hydroxy‐2‐styrylchromones with ortho‐benzoquinodimethane, generated “in situ” by thermal extrusion of sulfur dioxide from 1,3‐dihydrobenzo[c]thiophene 2,2‐dioxide, leads to 2‐(3‐aryl‐1,2,3,4‐tetrahydronaphth‐2‐yl)‐5‐hydroxychromones. These cycloadducts were dehydrogenated with DDQ, using classical thermal reflux conditions and microwave irradiation, affording the corresponding 2‐(3‐arylnaphth‐2‐yl)‐5‐hydroxychromones in high yields (48‐96%). 相似文献
2.
Daniel E. Lynch Ian McClenaghan 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(12):o704-o707
The structure of 2‐(pyrrolidin‐1‐yl)‐1,4‐naphthoquinone, C14H12.95Cl0.05NO2, (I), is actually a 0.95:0.05 mixture including 2‐chloro‐3‐(pyrrolidin‐1‐yl)‐1,4‐naphthoquinone as a minor impurity, but (I) was resolved as a single molecule containing a Cl atom with 5% occupancy at the 3‐position. Compound (I) was prepared from the fully chloro‐substituted analogue in an attempt to produce the disubstituted pyrrolidinyl derivative. 2‐Phenylsulfanyl‐3‐(pyrrolidin‐1‐yl)‐1,4‐naphthoquinone, C20H17NO2S, (II), was also prepared from 2‐chloro‐3‐(pyrrolidin‐1‐yl)‐1,4‐naphthoquinone, using a strong exocyclic nucleophile. The structure of (II) differs from previous structures of 2,3‐dichloro‐1,4‐naphthoquinone and its derivatives in that the naphthoquinone ring is non‐planar. 相似文献
3.
Daniel E. Lynch Ian McClenaghan 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(12):e588-e588
The structure of the title compound, C14H12ClNO2, (I), comprises essentially planar molecules which crystallize in a monoclinic lattice. C—H?O interactions exist to both naphthoquinone O atoms and the Cl atom. 相似文献
4.
Fernando Castaeda Christian Aliaga Clifford A. Bunton María Teresa Garland Ricardo Baggio 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(8):o496-o499
The title ylides, 3‐(triphenylphosphoranylidene)pentane‐2,4‐dione, C23H21O2P, (I), and diethyl 2‐(triphenylphosphoranylidene)malonate, C25H25O4P, (II), differ in the conformations adopted by their extended ylide moieties. In (I), one carbonyl O atom is syn and the other is anti with respect to the P atom, the ylide group is nearly planar, with a maximum P—C—(C=O) angle of 18.2 (2)°, and the P—C, C—C and C=O bond lengths are consistent with electronic delocalization involving the O atoms. In (II), both carbonyl O atoms are anti and the ester groups are twisted out of the plane of the near trigonal ylide C atom, reducing delocalization, the largest P—C—(C=O) angle being 30.2 (2)°. 相似文献
5.
Jan W. Bats Matthias Gerlach Michael Reggelin Matthias Kck 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(11):o664-o666
The structure of the title compound, C14H18O5, has two independent molecules related by a local noncrystallographic a‐glide plane perpendicular to the b axis. The pseudo‐glide plane shows a discontinuity at z = 0. Both molecules have an intramolecular hydrogen bond between the hydroxy and aldehyde groups. There are stacks of molecules along the a‐axis direction. Neighboring molecules in the stack have an interplanar angle of 1.6 (1)°, interplanar distances ranging between 3.399 (3) and 3.417 (3) Å, and a ring offset of 1.38 (1) Å. 相似文献
6.
Ewa Rozycka‐Sokolowska Andrzej Borowski Bernard Marciniak 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(6):o209-o211
The structure of the title compound, C6H6OS, exhibits a flip‐type disorder of the thiophene ring [occupancy ratio = 0.848 (3):0.152 (3)], which is typical for many thiophene derivatives. The puckered thiophene ring is essentially coplanar with the plane formed by the non‐H atoms of the acetyl substituent, similar to its simple analogues, i.e. 3‐acetyl‐2‐carboxythiophene, 4‐acetyl‐3‐carboxythiophene and 3,5‐diacetyl‐2‐ethylamino‐4‐methylthiophene. In the crystal structure, molecules are connected by C—H...π hydrogen bonds, forming a sheet parallel to the (001) plane. Moreover, an inspection of the crystal lattice reveals that there are short S...O contacts connecting the molecules of adjacent sheets. Comparison of the title crystal structure with its simple 3‐methoxythiophene analogue shows a close similarity in the herringbone arrangement of molecules and in the presence of C—H...π interactions and S...O contacts. 相似文献
7.
Vijayakumar N. Sonar Sean Parkin Peter A. Crooks 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(12):o743-o745
The title compounds, C20H17NO3S, (I), and C19H15NO2S, (II), were prepared by the reaction of benzo[b]thiophene‐2‐carbaldehyde with (3,4,5‐trimethoxyphenyl)acetonitrile and (3,4‐dimethoxyphenyl)acetonitrile, respectively, in the presence of methanolic potassium hydroxide. In (I), the C=C bond linking the benzo[b]thiophene and the 3,4,5‐trimethoxyphenyl units has E geometry, with dihedral angles between the plane of the bridging unit and the planes of the two adjacent ring systems of 5.2 (3) and 13.1 (2)°, respectively. However, in (II), the C=C bond has Z geometry, with dihedral angles between the plane of the bridging unit and the planes of the adjacent benzo[b]thiophene and 3,4‐dimethoxyphenyl units of 4.84 (17) and 76.09 (7)°, respectively. There are no significant intermolecular hydrogen‐bonding interactions in the packing of (I) and (II). The packing is essentially stabilized via van der Waals forces. 相似文献
8.
Nevzat Karaday ükriye akmak Mustafa Odabaolu Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(5):o303-o305
The title 4,4′‐disubstituted diphenyl‐1,3‐triazines, C14H15N3, (I), C12H9ClFN3, (II), and C13H12FN3, (III), each contain a triazene group (–N=N—NH–) having an extended conformation. The dihedral angles between the two benzene rings in (I), (II) and (III) are 4.3, 3.4 and 6.5°, respectively. The molecules are almost entirely planar, with maximum deviations from the mean planes of 0.1087 (2), −0.1072 (7) and 0.1401 (3) Å, respectively. In each compound, the molecules are linked by N—H⋯N hydrogen bonds to form chains and pack similarly in the crystal structures. 相似文献
9.
Vladimir V. Kouznetsov Diego F. Amado Ali Bahsas Juan Amaro‐Luis 《Journal of heterocyclic chemistry》2006,43(2):447-452
New αω‐bis‐(2‐hetaryl‐4‐oxothiazolidin‐3‐yl)alkanes were prepared via a common two step procedure using N,N‐bis‐hetarylidenamines condensation with α‐mercaptoacetic acid. The used bis‐aldimines were obtained from reaction between ethylenediamine or putrescine and benzaldehyde or the isomeric pyridinecarboxyaldehydes. The bis‐(2‐phenyl‐4‐oxothiazolidin‐3‐yl)alkanes were prepared by one‐pot three component reaction of diamine, aldehyde and α‐mercaptoacetic acid under very mild conditions. 相似文献
10.
Youquan Zhu Pei Liu Danyang Wang Jin Zhang Jie Cheng Yuan Ma Xiaomao Zou Huazheng Yang 《中国化学》2013,31(2):173-181
A series of novel N‐(4‐(2‐aryloxythiazol‐5‐yl)but‐3‐yn‐2‐yl)benzamide derivatives were designed and synthesized. Their structures were identified by 1H NMR and elemental analyses. Preliminary bioassays indicated that some title compounds provided >80% control of Sclerotinia sclerotiorum at 50 µg/mL and >70% herbicidal activities against B. campestris at 100 µg/mL. Their structure‐activities relationships were also discussed. 相似文献
11.
Vijayakumar N. Sonar Sean Parkin Peter A. Crooks 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(3):o217-o218
The title compound, C16H12N2S, has been synthesized by base‐catalyzed condensation of 1‐methylindole‐3‐carboxaldehyde with thiophene‐3‐acetonitrile. The product assumes an approximately planar Z configuration. The molecule has a thienyl‐ring flip disorder. 相似文献
12.
Ratnadeep S. Joshi Priyanka G. Mandhane Wajid Khan Charansingh H. Gill 《Journal of heterocyclic chemistry》2011,48(4):872-876
A new series of 2‐(p‐tolyloxy)‐3‐(5‐(pyridin‐4‐yl)‐1,3,4‐oxadiazol‐2‐yl)quinoline were synthesized from oxidative cyclization of N′‐((2‐(p‐tolyloxy)quinoline‐3‐yl)methylene)isonicotinohydrazide in DMSO/I2 at reflux condition for 3–4 h. The structures of the new compounds were confirmed by elemental analyses as well as IR, 1H‐NMR, and mass spectral data. All the synthesized compounds were screened for their antibacterial activities against various bacterial strains. Several of these compounds showed potential antibacterial activity. J. Heterocyclic Chem., (2011). 相似文献
13.
Renaud Belin Monique Tillard Jean‐Louis Maurel Jean‐Paul Ribet 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(4):483-484
The title compound, C12H14FN2O3+·Br?, crystallizes in the non‐centrosymmetric P212121 space group. The absolute configuration of the pharmacologically active molecule could be resolved in the hydrobromide salt, the structure of which is reported. The molecule of the title compound has the S configuration. The molecular packing in the crystal is stabilized by weak N—H?Br [N?Br = 3.240 (4) and 3.302 (4) Å] hydrogen bonding. 相似文献
14.
Min‐Jung Lee Moon Seong Kang Min‐Ki Shin Jong‐Won Park Dae Sung Chung Chan Eun Park Soon‐Ki Kwon Yun‐Hi Kim 《Journal of polymer science. Part A, Polymer chemistry》2010,48(18):3942-3949
New amorphous semiconducting copolymers, poly(9,9‐dialkylfluorene)‐alt‐(3‐dodecylthienyl‐divinylbenzene‐3‐dodecylthienyl) derivatives (PEFTVB and POFTVB), were designed, synthesized, and characterized. The structure of copolymers was confirmed by H NMR, IR, and elemental analysis. The copolymers showed very good solubility in organic solvents and high thermal stability with high Tg of 178–185 °C. The weight average molecular weight was found to be 107,900 with polydispersity of 3.14 for PEFTVB and 76,700 with that of 3.31 for POFTVB. UV–vis absorption studies showed the maximum absorption at 428 nm (in solution) and 435 nm (in film) for PEFTVB and at 430 nm (in solution) and 436 nm (in film) for POFTVB. Photoluminescence studies showed the emission at 498 nm (in solution) and 557 nm (in film) for PEFTVB and at 498 nm (in solution) and 536 nm (in film) for POFTVB. The solution‐processed thin‐film transistors showed the carrier mobility of 2 × 10?4 cm2 V?1 s?1 for PEFTVB‐based devices and 2 × 10?5 cm2 V?1 s?1 for POFTVB‐based devices. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3942–3949, 2010 相似文献
15.
Alessandra Forni Julieta Gradinaru 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(6):o342-o344
The structure of the title S‐alkylated isothiosemicarbazide, C12H15N3OS, was determined by single‐crystal diffractometry and compared with the structures of other compounds containing the S‐alkylthiosemicarbazide moiety. Such structures cluster into two groups, according to the different orientation of the –SR group with respect to the hydrazine N atom of the thiosemicarbazide. The cis arrangement is preferred by most molecules in the solid state, in spite of the possibility of intramolecular N—H?N interactions in the opposite orientation. 相似文献
16.
Oscar F. Vazquez‐Vuelvas Julia V. Hernndez‐Madrigal Armando Pineda‐Contreras Simn Hernndez‐Ortega Reyna Reyes‐Martínez David Morales‐Morales 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(3):175-180
Two isomeric pyridine‐substituted norbornenedicarboximide derivatives, namely N‐(pyridin‐2‐yl)‐exo‐norbornene‐5,6‐dicarboximide, (I), and N‐(pyridin‐3‐yl)‐exo‐norbornene‐5,6‐dicarboximide, (II), both C14H12N2O4, have been crystallized and their structures unequivocally determined by single‐crystal X‐ray diffraction. The molecules consist of norbornene moieties fused to a dicarboximide ring substituted at the N atom by either pyridin‐2‐yl or pyridin‐3‐yl in an anti configuration with respect to the double bond, thus affording exo isomers. In both compounds, the asymmetric unit consists of two independent molecules (Z′ = 2). In compound (I), the pyridine rings of the two independent molecules adopt different conformations, i.e. syn and anti, with respect to the methylene bridge. The intermolecular contacts of (I) are dominated by C—H...O interactions. In contrast, in compound (II), the pyridine rings of both molecules have an anti conformation and the two independent molecules are linked by carbonyl–carbonyl interactions, as well as by C—H...O and C—H...N contacts. 相似文献
17.
Abhijit Mitra Pamela J. Seaton Kraig A. Wheeler 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(9):o581-o582
The title new diquinaldine derivative, C27H24N4, forms molecular assemblies organized by intermolecular quinoline π–π stacking [3.356 (3) and 3.440 (3) Å] and both inter‐ and intramolecular N—H⋯N hydrogen bonds [3.039 (3)–3.104 (3) Å and 129 (2)–172 (2)°]. The combination of such interactions provides readily definable contacts that propagate along each crystallographic axis. 相似文献
18.
Sankar Prasad Dey Dilip Kumar Dey Asok Kumar Mallik Lutz Dahlenburg 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(6):o321-o322
The title compound, 2‐hydroxyphenyl 5‐(pyrrol‐2‐yl)‐3H‐pyrrolizin‐6‐yl ketone, C18H14N2O2, was isolated from the base‐catalyzed 1:2 condensation of 2‐hydroxyacetophenone with pyrrole‐2‐carbaldehyde. The pyrrole N—H and hydroxybenzoyl O—H groups are hydrogen bonded to the benzoyl O atom. The allylic C=C double bond of the 3H‐pyrrolizine system is located between ring positions 1 and 2, the C atom at position 3 (adjacent to the N atom) being single bonded. 相似文献
19.
2‐Formylchromones and 3‐formylchromones as the first materials singly reacted with 2‐amino‐5‐mercapto‐1,3,4‐thiadiazole to give the corresponding Schiff bases, which on cyclocondensation with mercapto‐acetic acid in 1,4‐dioxane yielded target compounds named 4‐oxo‐thiazolidines. The structures of all the synthetic compounds were confirmed by elemental analysis and IR, 1H NMR, LC‐MS (ESI) spectral data. 相似文献
20.
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 下载免费PDF全文
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