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1.
Dr. Hong‐Peng Jia Dr. Jie Ding Dr. Ying‐Fen Ran Dr. Shi‐Xia Liu Dr. Carmen Blum Dr. Irina Petkova Prof. Andreas Hauser Prof. Silvio Decurtins 《化学:亚洲杂志》2011,6(12):3312-3321
An efficient synthetic approach to a symmetrically functionalized tetrathiafulvalene (TTF) derivative with two diamine moieties, 2‐[5,6‐diamino‐4,7‐bis(4‐pentylphenoxy)‐1,3‐benzodithiol‐2‐ylidene]‐4,7‐bis(4‐pentylphenoxy)‐1,3‐benzodithiole‐5,6‐diamine ( 2 ), is reported. The subsequent Schiff‐base reactions of 2 afford large π‐conjugated multiple donor–acceptor (D–A) arrays, for example, the triad 2‐[4,9‐bis(4‐pentylphenoxy)‐1,3‐dithiolo[4,5‐g]quinoxalin‐2‐ylidene]‐4,9‐bis(4‐pentylphenoxy)‐1,3‐dithiolo[4,5‐g]quinoxaline ( 8 ) and the corresponding tetrabenz[bc,ef,hi,uv]ovalene‐fused pentad 1 , in good yields and high purity. The novel redox‐active nanographene 1 is so far the largest known TTF‐functionalized polycyclic aromatic hydrocarbon (PAH) with a well‐resolved 1H NMR spectrum. The electrochemically highly amphoteric pentad 1 and triad 8 exhibit various electronically excited charge‐transfer states in different oxidation states, thus leading to intense optical intramolecular charge‐transfer (ICT) absorbances over a wide spectral range. The chemical and electrochemical oxidations of 1 result in an unprecedented TTF?+ radical cation dimerization, thereby leading to the formation of [ 1 ?+]2 at room temperature in solution due to the stabilizing effect, which arises from strong π–π interactions. Moreover, ICT fluorescence is observed with large solvent‐dependent Stokes shifts and quantum efficiencies of 0.05 for 1 and 0.035 for 8 in dichloromethane. 相似文献
2.
Dr. Iwona Olejniczak Arkadiusz Frąckowiak Prof. Roman Świetlik Dr. Tatiana G. Prokhorova Prof. Eduard B. Yagubskii 《Chemphyschem》2013,14(17):3925-3935
The polarized infrared reflectance and Raman spectra of the three quasi‐two‐dimensional β′′‐(BEDT‐TTF)4[(H3O)Fe(C2O4)3]?Y bifunctional charge‐transfer salts, where BEDT‐TTF=bis(ethylenedithio)tetrathiafulvalene and Y=C6H5Br, (C6H5CN)0.17(C6H5Br)0.83, (C6H5CN)0.4(C6H5F)0.6, have been measured as a function of the temperature. Signatures of charge inhomogenity have been found in both Raman and infrared spectra of the β′′‐(BEDT‐TTF)4[(H3O)Fe(C2O4)3]?Y superconductors. A 100 K transition to a mixed insulating/metallic state is clearly seen for the first time in the temperature dependence of the electronic spectra of superconducting β′′‐(BEDT‐TTF)4[(H3O)Fe(C2O4)3]?C6H5Br. We suggest that this phase transition is due to subtle changes in the ethylene groups ordering, which are related to a structural phase transition in the anionic layer. The infrared and Raman spectra of quasi‐two‐dimensional metal α‐′pseudo‐κ′‐(BEDT‐TTF)4[(H3O)Fe(C2O4)3]C6H4Br2 are also investigated. 相似文献
3.
Roberta Billi Barbara Cosimelli Domenico Spinelli Alberto Leoni 《Journal of heterocyclic chemistry》2000,37(4):875-878
The reaction of 6‐(4‐chlorophenyl)‐5‐nitrosoimidazo[2,1‐b][1,3]thiazole 1b , 6‐(4‐chlorophenyl)‐2‐methyl‐5‐nitrosoimidazo[2,1‐b][1,3]thiazole 1c , 6‐(4‐chlorophenyl)‐2,3‐dimethyl‐5‐nitrosoimidazo‐[2,1‐b][1,3]thiazole 1d and 2‐(4‐chlorophenyl)‐3‐nitrosobenzo[d]imidazo[2,1‐b][1,3]thiazole 1e with hydrochloric acid has been carried out in order to investigate the effect of substituents on the thiazole ring in a recently reported ring‐ring interconversion reaction. In every case the corresponding [1,4]‐thiazino[3,4‐c][1,2,4]oxadiazol‐3‐ones 2b‐e have been obtained. In particular, the benzoderivative 1e furnished the 4‐(4‐chlorophenyl)‐4‐hydroxy‐4H‐benzo[5,6][1,4]thiazino[3,4‐c][1,2,4]oxadiazol‐1‐one 2e , containing a new tricyclic system with a quasi‐planar geometry whose pharmacological potentialities appear promising. 相似文献
4.
Vratislav Langer Bohumil Steiner Miroslav Ko 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(4):o151-o154
In the title compounds, C12H20O6, (I), and C9H16O6, (II), the five‐membered furanose ring adopts a 4T3 conformation and the five‐membered 1,3‐dioxolane ring adopts an E3 conformation. The six‐membered 1,3‐dioxane ring in (I) adopts an almost ideal OC3 conformation. The hydrogen‐bonding patterns for these compounds differ substantially: (I) features just one intramolecular O—H...O hydrogen bond [O...O = 2.933 (3) Å], whereas (II) exhibits, apart from the corresponding intramolecular O—H...O hydrogen bond [O...O = 2.7638 (13) Å], two intermolecular bonds of this type [O...O = 2.7708 (13) and 2.7730 (12) Å]. This study illustrates both the similarity between the conformations of furanose, 1,3‐dioxolane and 1,3‐dioxane rings in analogous isopropylidene‐substituted carbohydrate structures and the only negligible influence of the presence of a 1,3‐dioxane ring on the conformations of furanose and 1,3‐dioxolane rings. In addition, in comparison with reported analogs, replacement of the –CH2OH group at the C1‐furanose position by another group can considerably affect the conformation of the 1,3‐dioxolane ring. 相似文献
5.
Krishnan Ravikumar Balasubramanian Sridhar Jagadeesh Babu Nanubolu Venkatasubramanian Hariharakrishnan Awadesh Narain Singh 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(8):o302-o307
6,8‐Dinitro‐2,4‐dihydro‐1H‐benzo[b][1,2,4]triazolo[4,3‐d][1,4]oxazin‐1‐one, C9H5N5O6, (I), a potential diuretic, and its acetylacetone derivative (E)‐2‐(2‐hydroxy‐4‐oxopent‐2‐en‐3‐yl)‐6,8‐dinitro‐2,4‐dihydro‐1H‐benzo[b][1,2,4]triazolo[4,3‐d][1,4]oxazin‐1‐one, C14H11N5O8, (II), both crystallize from methanol but in centrosymmetric and noncentrosymmetric space groups, respectively. To the best of our knowledge, this is the first report of crystal structures of benzoxazine–triazole fused systems. The acetylacetone group in (II) exists as the keto–enol tautomer and is oriented perpendicular to the triazol‐3‐one ring. Of the two nitro groups present, one is rotated significantly less than the other in both structures. The oxazine ring adopts a screw‐boat conformation in (II), whereas it is almost planar in (I). N—H...N and N—H...O hydrogen bonds form centrosymmetric dimers in (I), while C—H...O interactions associate the molecules into helical columns in (II). 相似文献
6.
Vratislav Langer Miroslav Ko Dalma Gyepesov Juraj Kronek Jozef Lusto Mariana Sldkovi
ov 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(10):o602-o606
Crystal structures are reported for three isomeric compounds, namely 2‐(2‐hydroxyphenyl)‐2‐oxazoline, (I), 2‐(3‐hydroxyphenyl)‐2‐oxazoline, (II), and 2‐(4‐hydroxyphenyl)‐2‐oxazoline, (III), all C9H9NO2 [systematic names: 2‐(4,5‐dihydro‐1,3‐oxazol‐2‐yl)phenol, (I), 3‐(4,5‐dihydro‐1,3‐oxazol‐2‐yl)phenol, (II), and 4‐(4,5‐dihydro‐1,3‐oxazol‐2‐yl)phenol, (III)]. In these compounds, the deviation from coplanarity of the oxazoline and benzene rings is dependent on the position of the hydroxy group on the benzene ring. The coplanar arrangement in (I) is stabilized by a strong intramolecular O—H⋯N hydrogen bond. Surprisingly, the 2‐oxazoline ring in molecule B of (II) adopts a 3T4 (C2TC3) conformation, while the 2‐oxazoline ring in molecule A, as well as that in (I) and (III), is nearly planar, as expected. Tetramers of molecules of (II) are formed and they are bound together via weak C—H⋯N hydrogen bonds. In (III), strong intermolecular O—H⋯N hydrogen bonds and weak intramolecular C—H⋯O hydrogen bonds lead to the formation of an infinite chain of molecules perpendicular to the b direction. This paper also reports a theoretical investigation of hydrogen bonds, based on density functional theory (DFT) employing periodic boundary conditions. 相似文献
7.
Michael D. Thompson 《Journal of heterocyclic chemistry》1986,23(5):1545-1549
The reaction conditions for the preparation of 7H,8H-1,3-dimethyl-2,4,6,9-tetraoxopyrimidino[4,5-b][1,4]-diazocine ( 9 ), 1,3-dimethy 1–2,4,6,11-tetraoxobenzo[f]pyrimidino[4,5-b][1,4]diazocine ( 10 ), 7H,8H-1,3-dimethyl-2,4,6,10-tetraoxopyrimidino[4,5-b][1,4]diazonine ( 16 ), and 7H,8H-6,9-dioxopyridino[2,3-b][1,4]diazocine ( 19 ) were determined. The mechanism of the formation of these compounds was established. The scope of these reactions was found to be general for eight and nine ring formation from 2,3-diamino-N-heterocycles. 相似文献
8.
Chao Fang Jian‐Ping Ma Sui Wei Yu‐Bin Dong 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(2):m35-m38
1,1′‐[(Ethane‐1,2‐diyldioxy)di‐o‐phenylene]bis(indoline‐2,3‐dione), C32H24N2O6, L or (I), adopts a trans conformation with the two terminal indoline‐2,3‐dione groups located on opposite sides of the central ether bridge, as required by a centre of inversion located at the mid‐point of the ethane C—C bond. However, in the discrete binuclear AgI metallocycle complex salt bis{μ‐1,1′‐[(ethane‐1,2‐diyldioxy)di‐o‐phenylene]bis(indoline‐2,3‐dione)}disilver(I) bis(hexafluoridoantimonate), [Ag2(C32H24N2O6)2][SbF6]2, (II), synthesized by combination of L with AgSbF6, L adopts a gauche conformation to bind AgIvia the two indolinedione O atoms and two C atoms from the phenoxy ring. One dione O atom from the opposite side of the ether bridge completes the irregular coordination environment of each AgI atom. The complex is on a centre of inversion located between the AgI atoms. In the solid state, these binuclear [Ag2L2]2+ metallocycles stack together via intermolecular π–π interactions to generate a one‐dimensional chain motif, with the [SbF6]− counter‐ions, which are disordered, located between the chains. 相似文献
9.
J. G. Rodríguez A. Lafuente C. De Los Ríos 《Journal of polymer science. Part A, Polymer chemistry》2004,42(23):6031-6040
Conjugated 1,4‐bis(n′‐quinolyl)‐1,3‐butadiynes were obtained through the oxidative dimerization of the corresponding n′‐ethynylquinolines catalyzed by cuprous chloride. Differential scanning calorimetry analysis of the 1,4‐bis[n′‐(quinolyl)]buta‐1,3‐diyne molecules produced evidence of a syn–anti rotational equilibrium around the 1,3‐diyne axis and an irreversible transformation into a thermopolymer. The topo‐oligomerization of 1,4‐bis[3′‐(quinolyl)]buta‐1,3‐diyne, which took place by irradiation with sunlight, was investigated with matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry. Accurate X‐ray molecular structure and refinement analysis of 1,4‐bis[3′‐(quinolyl)]buta‐1,3‐diyne was conducted. The molecular crystalline packing consisted of parallel arrays of two groups of centrosymmetric molecules (antirotamer) in a herringbone assemblage in the solid state. The polymerization of 3‐ethynylquinoline was carried out with the AlEt3/V(acac)3 system to produce a mixture of 1,2,4‐ and 1,3,5‐tris(3′‐quinolyl)benzene cyclotrimers and a trans–cisoid polyene structure. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 6031–6040, 2004 相似文献
10.
Shi‐Ping Yang Xi‐Bin Yu Ji‐Guang Huang Han‐Hong Xu 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(7):o392-o393
The structure determination of the title compound, rotenone α‐oxime [systematic name: 1,2,12,12a‐tetrahydro‐8,9‐dimethoxy‐2‐(1‐methylethenyl)‐[1]benzopyrano[3,4‐b]furo[2,3‐h][1]benzopyran‐6(6H)‐one oxime], C23H23NO6, confirms that the molecule has an approximately V‐shaped structure. One of the rings has a typical cyclohexene‐like monoplanar conformation and the central ring adopts a 1,2‐diplanar conformation. 相似文献
11.
Study of 1,3‐Dipolar Cycloaddition and Ring Contraction of New 1,4‐Phenylene‐bis[1,5]benzothiazepine Derivatives 下载免费PDF全文
Some 1,4‐phenylene‐bis[1,2,4]oxadiazolo‐[5,4‐d][1,5]benzothiazepine derivatives ( 4a , 4b , 4c ) were synthesized by 1,3‐dipolar cycloaddition reaction of benzohydroximinoyl chloride with 1,4‐phenylene‐bis(4‐aryl)‐2,3‐dihydro[1,5]benzothiazepine ( 2a , 2b , 2c ); meanwhile, compounds 2a , 2b , 2c also occurred ring contraction under acylating condition to obtain bis[2‐aryl‐2′‐(β‐1,4‐phenylenevinyl)‐3‐acetyl]‐2,3‐dihydro[1,5]benzothiazoles ( 3a , 3b , 3c ). The structures of some novel compounds were confirmed by IR, 1H‐NMR, elemental, and X‐ray crystallographic analysis. 相似文献
12.
Sndor L. Bek Jan W. Bats Martin U. Schmidt 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(2):o45-o50
2‐Ammonio‐5‐chloro‐4‐methylbenzenesulfonate, C7H8ClNO3S, (Ia), is an intermediate in the synthesis of lake red azo pigments. The present structure determination from single‐crystal data confirms the results of a previous powder diffraction determination [Bekö, Thoms, Brüning, Alig, van de Streek, Lakatos, Glaubitz & Schmidt (2010). Z. Kristallogr. 225 , 382–387]. The zwitterionic tautomeric form is confirmed. During a polymorph screening, two additional pseudopolymorphs were obtained, viz. 2‐ammonio‐5‐chloro‐4‐methylbenzenesulfonate 1‐methyl‐2‐pyrrolidone monosolvate, C7H8ClNO3S·C5H9NO, (Ib), and 2‐ammonio‐5‐chloro‐4‐methylbenzenesulfonate dimethyl sulfoxide monosolvate, C7H8ClNO3S·C2H6OS, (Ic). The molecules of (Ib) have crystallographic m symmetry. The 1‐methyl‐2‐pyrrolidone solvent molecule has an envelope conformation and is disordered around the mirror plane. The structure shows hydrogen‐bonded ladders of molecules [graph‐set notation C22(6)R22(12)] in the [010] direction. The benzene groups of adjacent ladders are also stacked in this direction. A different type of hydrogen‐bonded ladder [graph‐set notation C(6)R22(4)R44(12)] occurs in (Ic). In (Ia), (Ib) and (Ic), the molecules correspond to the zwitterionic tautomer. The structure of the cocrystal of 4‐aminobenzenesulfonic acid with 1,4‐bis(4,5‐dihydroimidazol‐2‐yl)benzene [Shang, Ren, Wang, Lu & Yang (2009). Acta Cryst. E 65 , o2221–o2222] is corrected; it actually contains 4‐aminobenzenesulfonate anions and 2,2′‐(1,4‐phenylene)di(dihydroimidazolium) dications, i.e. 2,2′‐(1,4‐phenylene)di(4,5‐dihydroimidazolium) bis(4‐aminobenzenesulfonate) dihydrate, C12H16N42+·2C6H6NO3S−·2H2O. Hence, all known structures of aminobenzenesulfonic acid complexes contain ionic or zwitterionic molecules; there is no known structure with a neutral aminobenzenesulfonic acid molecule. 相似文献
13.
Juan C. Castillo Rodrigo Abonía Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(5):544-548
In the molecule of 4‐(2‐chlorophenyl)pyrrolo[1,2‐a]quinoxaline, C17H11ClN2, (I), the bond lengths are consistent with electron delocalization in the two outer rings of the fused tricyclic system, with a localized double bond in the central ring. The molecules of (I) are linked into chains by a π–π stacking interaction. In (4RS)‐4‐(1,3‐benzodioxol‐6‐yl)‐4,5‐dihydropyrrolo[1,2‐a]quinoxaline, C18H14N2O2, (II), the central ring of the fused tricyclic system adopts a conformation intermediate between screw‐boat and half‐chair forms. A combination of N—H...O and C—H...π(arene) hydrogen bonds links the molecules of (II) into a sheet. Comparisons are made with related compounds. 相似文献
14.
Kuppuswamy Arumugam Daniel Seth Clark Joel T. Mague James P. Donahue 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(11):o446-o449
The crystal structures of 4,5‐bis(bromomethyl)‐1,3‐dithiol‐2‐one, C5H4Br2OS2, (I), and 4,5‐bis[(dihydroxyphosphoryl)methyl]‐1,3‐dithiol‐2‐one, C5H8O7P2S2, (II), occur with similar unit cells in the same monoclinic space group. Both molecules reside on a twofold symmetry axis coincident with the C=O bond, so that the substituents in the 4‐ and 5‐positions project above and below the plane of the 1,3‐dithiol‐2‐one ring. In both structures, the molecules align themselves in a head‐to‐tail fashion along the b axis, and these rows of molecules then stack, with alternating directionality, along the c axis. For (II), an extensive network of intermolecular hydrogen bonds occurs between molecules within the same stack and between adjacent stacks. Each –CH2P(O)(OH)2 group participates in four hydrogen bonds, twice as donor and twice as acceptor. 相似文献
15.
Dong Liu 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(2):m34-m36
Solvothermal reaction between Cd(NO3)2, 1,4‐phenylenediacetate (1,4‐PDA) and 1,3‐bis(pyridin‐4‐yl)propane (bpp) afforded the title complex, [Cd(C10H8O4)(C13H14N2)]n. Adjacent carboxylate‐bridged CdII ions are related by an inversion centre. The 1,4‐PDA ligands adopt a cis conformation and connect the CdII ions to form a one‐dimensional chain extending along the c axis. These chains are in turn linked into a two‐dimensional network through bpp bridges. The bpp ligands adopt an anti–gauche conformation. From a topological point of view, each bpp ligand and each pair of 1,4‐PDA ligands can be considered as linkers, while the dinuclear CdII unit can be regarded as a 6‐connecting node. Thus, the structure can be simplified to a two‐dimensional 6‐connected network. 相似文献
16.
Colm Crean John F. Gallagher Albert C. Pratt 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):o36-o38
The title complex, C17H9N5·C6H4S4, contains π‐deficient bis(dinitrile) and TTF molecules stacked alternately in columns along the a‐axis direction; the interplanar angle between the TTF molecule and the isoindolinyl C4N[C(CN)2]2 moiety is 1.21 (4)°. The N‐allyl moiety in the TCPI molecule is oriented at an angle of 87.10 (10)° with respect to the five‐membered C4N ring, and the four C[triple‐bond]N bond lengths range from 1.134 (3) to 1.142 (3) Å, with C—C[triple‐bond]N angles in the range 174.3 (3)–176.9 (2)°. In the TTF system, the S—C bond lengths are 1.726 (3)–1.740 (3) and 1.751 (2)–1.763 (2) Å for the external S—C(H) and internal S—C(S) bonds, respectively. 相似文献
17.
Bin Li Hai‐Bin Song Chi‐Tung Hsu Ke‐Liang Zhang Chao Wu Hua‐Zheng Yang 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(2):o114-o117
The molecular structures of 2‐[4‐chloro‐2‐fluoro‐5‐(prop‐2‐ynyloxy)phenyl]‐1,3,4,5,6,7‐hexahydroisoindole‐1,3‐dione, C17H13ClFNO3, (I), and the isomeric compound 2‐[4‐chloro‐2‐fluoro‐5‐(prop‐2‐ynyloxy)phenyl]‐cis‐1,3,3a,4,7,7a‐hexahydroisoindole‐1,3‐dione, (II), are, as anticipated, significantly different in their conformations and in the distances between the farthest two atoms. The six‐membered ring of the 1,3,4,5,6,7‐hexahydroisoindole‐1,3‐dione moiety in (I) adopts a half‐chair conformation. The dihedral angle between the five‐membered dione ring of (I) and the benzene ring is 50.96 (7)°. The six‐membered ring of the cis‐1,3,3a,4,7,7a‐hexahydroisoindole‐1,3‐dione moiety in (II) adopts a boat conformation. The dihedral angle in (II) between the five‐membered dione ring and the benzene ring is 61.03 (13)°. In the crystal structures, the molecules are linked by C—H⋯O hydrogen bonds and weak π–π interactions. Compound (I) is a much more potent herbicide than (II). The Cl⋯H distances between the farthest two atoms in (I) and (II) are 11.37 and 9.97 Å, respectively. 相似文献
18.
Insuasty O. Braulio Insuasty I. Henry Quiroga P. Jairo Claudio Saitz Carolina Jullian 《Journal of heterocyclic chemistry》2000,37(2):401-403
Several new 6‐amino‐ and 6,8‐diamino‐4‐aryl‐2,3‐dihydropyrimido[4,5‐b][1,4]diazepines were obtained from the reaction of 4,5,6‐triaminopyrimidine 1a and 2,4,5,6‐tetraaminopyrimidine 1b with one equivalent of 3‐dimethylaminopropiophenones 2 in absolute ethanol. Structure analysis of 6‐amino‐ and 6,8‐diamino‐4‐aryl‐2,3‐dihydropyrimido[4,5‐b][1,4]diazepines 3a‐i , determined by detailed nmr measurements, reveals a high regioselectivity of this reaction. 相似文献
19.
With a variation in reaction conditions, 1, 4‐bis (2‐(2‐chloroethoxy)ethoxy)‐calix[6]arene (3) and l,3,5‐tris(2‐(2‐chloroethoxy) ethoxy)‐calix [6] arene (4) or 4 and 4‐chloroethoxyethoxy‐calix[6]crown‐3 (5) were selectively synthesized from p‐tert‐butyl‐calix [6] arene and 2‐(2‐chloroethoxy)ethyltosylate. l,3–4,6‐p‐tert‐butylcalix[6]‐bis‐crown‐3 (6) with (u,u,u,d,d,d) conformation and 1,3–4,5‐p‐tert‐butylcalix[6]‐biscrown‐3 (7) with self‐anchored (u,u, u, u, u, d) conformation were synthesized through an intramolecularly ring‐closing condensation of 1, 4‐bis (2‐(2‐chloroethoxy)ethoxy)‐p‐tert‐butyl‐calix[6]arene (3) in 25% and 15% yield, respectively. Using 5 instead of 3, only 7 was obtained in 65% high yield. 6 and 7 show different complexation properties toward alkali metal and ammonium ions. 相似文献
20.
Synthesis of Heterocyclic Analogs of α‐aminoadipic Acid and its Esters Based on Imidazo[2,1‐b][1,3]Thiazole 下载免费PDF全文
Algirdas Šačkus Diana Bričkutė Osvaldas Paliulis Frank Abildgaard Sløk 《Journal of heterocyclic chemistry》2015,52(4):1032-1036
A method for the preparation of heterocyclic analogs of α‐aminoadipic acid and its esters based on the imidazo[2,1‐b][1,3]thiazole ring system was developed. In this method, free‐radical bromination of ethyl 6‐methylimidazo[2,1‐b][1,3]thiazole‐5‐carboxylate with NBS afforded a versatile building block, ethyl 6‐bromomethylimidazo[2,1‐b][1,3]thiazole‐5‐carboxylate. Coupling of ethyl 6‐bromomethylimidazo[2,1‐b][1,3]thiazole‐5‐carboxylate with Schöllkopf's chiral auxiliary followed by acidic hydrolysis generated ethyl 6‐[(2S)‐2‐amino‐3‐methoxy‐3‐oxopropyl]imidazo[2,1‐b][1,3]thiazole‐5‐carboxylate. A similar procedure using diethyl (Boc‐amino)malonate yielded racemic 2‐amino‐3‐[(5‐ethoxycarbonyl)imidazo[2,1‐b][1,3]thiazol‐6‐yl]propanoic acid. 相似文献