Basicities and structures of 2-(N-arylaminomethylene)-3(2H)-benzo[b]thiophenones,-benzo[b]furanones,and -benzo[b]selenophenones

The ionization constants of the conjugate acids of the reaction series 2-(N-arylaminomethylene)-3(2H)-benzo[b]thiophenones,-benzo[b]furanones, and -benzo[b]selenophenones were determined by potentiometric titration in anhydrous acetonitrile. The electronic and vibrational spectroscopic data showed that the protonation center in the molecules of these compounds is the carbonyl oxygen atom. It was established by correlation analysis that N-aryl substituents affect the protonation center primarily via an induction mechanism.Communication XVIII from the series Basicities and structures of azomethines and their structural analogs. See [1] for communication XVII.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. pp. 619–623, May, 1977.     

Low-temperature X-ray study of benzoid-quinoid tautomerism in crystals of 2-(N,N-diphenylhydrazinoethylidene)-3(2H)-benzo[b]thiophenone

An X-ray investigation of 2-(N,N-diphenylhydrazinoethylidene)-3(2H)-benzo[b]thiophenone was performed at room and low (–80 °C) temperatures. It was established that the structure of this compound in the crystalline state at R-20 °C is intermediate between the ketoenehydrazine and hydroxyhydrazone forms, while at –80 °C the molecular structure is completely transformed to the hydroxyhydrazone form. This confirms the dynamic nature of hydrogen atom disordering in the molecule at 20 °C.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 104–106, January, 1995.This work was financially supported by the Russian Foundation for Basic Research (Project No. 93-03-04355).     

Structure and photochemical properties of 2-(N-benzoyl-N-phenylaminomethylene)- and 2-(N-p-nitrobenzoyl-N-phenylaminomethylene)-3(2H)-benzo[b]thiophenones

Conclusions It was established by x-ray crystallographic investigation that the inhibition of the photochromism of the nitro derivative (IIb) compared with compounds (I) and (IIa) is due to the difference in the structure of the molecules and to the realization of the low-lying triplet n^* state, due to the presence of the p-nitro group. The flattening of the p-nitrobenzoyl fragment and its rotation from the plane of the molecule evidently promote localization of the photoexcitation energy in this conjugated fragment of the molecule and lead to nonradiative deactivation of the excited S^1* state by intercombination conversion through the n triplet state and, finally, to a marked decrease in the yields of the fluorescence and the phototransformations.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1544–1548, July, 1989.The authors are grateful to M. I. Knyazhanskii for assistance in the discussion of the results.     

1,2-二[3-(6,8-二叔丁基-3,4-二氢-1,3-苯并嗪)基]乙烷的合成及晶体结构

~~1,2-二[3-(6,8-二叔丁基-3,4-二氢-1,3-苯并噁嗪)基]乙烷的合成及晶体结构@徐小平$苏州大学化学化工学院!江苏省有机合成重点实验室,江苏苏州215006 @姚英明$苏州大学化学化工学院!江苏省有机合成重点实验室,江苏苏州215006 @赵艺萍$江阴市长泾中学!江苏江阴214411 @张勇$苏州大学化学化工学院!江苏省有机合成重点实验室,江苏苏州215006 @沈琪$苏州大学化学化工学院!江苏省有机合成重点实验室,江苏苏州2150061,2-二[3-(6,8-二叔丁基.3,4-二氢-1,3-苯并噁嗪)基]乙烷;;合成;;晶体结构[1] Neuvonen K,Pihlaja K. J. Chan. Soc…     

Benzoid-quinoid tautomerism in azomethines and their structural analogs. 40. Synthesis and structure of 2-(aminobenzylidene)-3(2H)-benzo[b]thiophenones

Some 2-benzoyl-3-alkoxybenzo[b]thiophenones, 2-[N-aryl(alkyl)aminobenzylidene]-3(2H)-benzo[b]thiophenones, and their N-formyl derivatives have been synthesized. According to their UV, IR, and PMR spectra, these have the aminobenzylideneketone structure.For Communication 39, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1043–1046, August, 1987.     

2-(2,6-二烷氧基苯基)苯并呋喃衍生物的合成

以焦性没食子酸、4-羟基苯甲醛和酚为原料, 以邻碘代苯酚与苯乙炔衍生物的Sonogashira偶联及其连串化反应生成苯并呋喃环为关键步骤, 设计合成了一系列2-(2 ,6 -二烷氧基苯基)苯并呋喃衍生物, 并对产物进行了¹H NMR, ¹³C NMR, MS等表征.     

The unusual structure of 3-hydro-2-acetylbenzo[b]thiophene hydrazones

The structure of N,N-disubstituted 3-hydroxy-2-acetylbenzo[b]thiophene hydrazones was investigated by x-ray structural analysis. 2-(N-Methyl-N-phenylhydrazinoethylidene)-3(2H)-benzo[b]thiophenone exists in the E-ketoenehydrazine form, and 2-(N,N-diphenylhydrazinoethylidene)-3(2H)-benzo[b]thiophenone in the crystals forms a structure intermediate between the ketoenehydrazine and hydroxyhydrazone forms.Institute of Chemical Physics in Chernogolovka, Russian Academy of Sciences, Chernogolovka 142432. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 4, pp. 917–922, April, 1992.     

Molecular and Crystal Structure of 4-[2-(4-Dimethy aminophenyl)ethenyl]-1-methypyridinium tetraphenylborate

The title compound, C40H39N2B, Mr=558.54, crystallizes in space group P21/c, monoclinic, a=18.013(3), b=10.821(2), c=17.321(3),β=112.20(1)°, V=3125.9(9)3, Z=4, Dc=1.187g/cm3, μ(MoKα)=0.068mm-1, F(000)=1192. The final R and wR(F2) are 0.0467 and 0.0972 for 2353 observed reflections (I>2σ(I)), respectively. In the title molecule, the pyridyl ring of the cation makes dihedral angle of 19.94° with the phenyl ring. The anion takes a slightly distorted tetrahedral geometry. In the crystal, along the screw axis b, the centrosymmetric anion pairs form double chains, which are in turn related by the glide plane c, forming double layers. The centrosymmetric cation pairs are related by screw axis b and located between the double sheets of the anion.     

[Ni(hmta)][SSP(OC10 H7-2)2]2的合成、谱学性质与晶体结构

O,O’-二烃基二硫代磷酸的铵盐和配合物在用作润滑油抗氧剂、燃油的添加剂、高分子材料的稳定剂和人造橡胶的硫化促进剂时,一般需要加入一些有机胺,这样可有效地缩减氧化作用[1]。为此人们合成了一些含简单链状多胺、简单氮杂环化合物的O,O’-二烷基二硫代磷酸的过渡金属配合物     

N-Substituierte Benzo [b]thiophen-3-acetamide und 3-(β-Aminoäthyl)-benzo [b]thiophene

Zusammenfassung Die Synthese der Titelverbindungen erfolgte über die Benzo[b]thiophen-3-essigsäure, deren Chlorid mit Diäthylamin und N-Methylpiperazin zu den entsprechenden N-substituierten Benzo[b]thiophen-3-acetamiden reagierte; diese wurden mit LiAlH₄ zu tertiären Aminen reduziert.Die Synthese der homologen 2-Methylverbindungen ging vom 2-Methyl-3-acetyl-benzo[b]thiophen aus: Haloformreaktion gab 2-Methyl-benzo[b]thiophen-3-carbonsäure;Wolff-Umlagerung des entsprechenden Diazomethylketons in Gegenwart von sekundären Aminen lieferte verschiedene N-substituierte 2-Methyl-benzo[b]thiophen-3-acetamide, von denen drei mit LiAlH₄ zu tertiären Aminen reduziert wurden.

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The title substances were synthesized using benzo[b]thiophene-3-acetic acid as an intermediate, the acid chloride of which reacted with diethylamine and N-methylpiperazine to give the corresponding N-substituted benzo[b]thiophene-3-acetamides; these were reduced by LiAlH₄ to tertiary amines.The synthesis of the homologous 2-methyl compounds started from 2-methyl-3-acetyl-benzo[b]thiophene: haloform reaction gave 2-methyl-benzo[b]thiophene-3-carboxylic acid;Wolff-rearrangement of the corresponding diazomethyl ketone in the presence of secondary amines yielded various N-substituted 2-methyl-benzo[b]thiophene-3-acetamides; three of them were reduced by LiAlH₄ to tertiary amines.

     

Cyclocondensation of 3(2H)-benzo[b]thiophenone and oxidation products obtained during these reactions

The cyclocondensation of 3(2H)-benzo[b] thiophenone under acidic conditions has been studied. The symmetrical cyclotrimer tris(benzo[b]thieno)[2,3:2',3':3',2']benzene was formed and under certain conditions also a rearranged cyclotrimer, tris(benzo[b]thienyl)[2,3:2',3':3',2']benzene.The formation of cyclotrimers was accompanied by oxidative coupling products involving the initially formed dimeric compound, 3-hydroxy-2,3-bibenzo[b]thienyl. During several of these reactions, a novel heterocycle, tris(benzo[b]thieno)[3,2-b:2',3'-d:2',3'-f]oxepin, was formed. The products were studied by mass spectrometry and fragmentation pathways were determined by a linked scanning technique.     

2-[N-Acetyl-N-(2-fluorenonyl)aminomethylene]benzo[b]- thiophen-3(2H)-one,a Molecular Fluorescent Switch

Russian Journal of Organic Chemistry -     

N-Substituierte 2-Methyl-3-aminoacetyl-benzo[b]thiophene und 2-Methyl-3-(α-hydroxy-β-amino-äthyl)-benzo[b]thiophene

Zusammenfassung Bromierung von 2-Methyl-3-acetyl-benzo[b]thiophen ergab 2-Methyl-3-bromacetyl-benzo[b]thiophen, das beim Umsetzen mit Dimethylamin, Morpholin und N-Methylpiperazin die entsprechend basisch substituierten 3-Acetylverbindungen lieferte. Diese wurden mit LiAlH₄ zu den -Hydroxyverbindungen reduziert.In ähnlicher Weise wurde auch 3-Diäthylaminoacetyl-benzo[b]thiophen dargestellt.

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Bromination of 2-methyl-3-acetyl-benzo[b]thiophene gave 2-methyl-3-bromacetyl-benzo[b]thiophene, which reacted with dimethylamine, morpholine and N-methylpiperazine to give the corresponding base-substituted 3-acetyl derivatives. These were reduced by LiAlH₄ to the -hydroxy compounds.Similarily 3-diethylaminoacetyl-benzo[b]thiophene was synthesized.

     

Analogs of propranolol. Synthesis of 3-alkylamino-1-(3-benzo[b]thienyloxy)-2-propanols

The synthesis by two alternative routes of 1-(3-benzo[b]thienyloxy)-3-isopropylamino-2-propanol hydrochloride ( 1a HCl), a thiophenic isoster of Propranolol, and related compounds, is reported. The protecting and enolizing properties of the 2-methoxycarbonyl group on benzo[b]thiophene-3-one, along with its facile removal, are utilized in the first route. In the second one, conversion of 3-bromobenzo[b]thiophene in 1-(3-benzo[b]thienyloxy)-2,3-o-isopropylidenepropane is the key step. On the other hand, hydrolysis of 1-(3-benzo[b]furanyloxy)-2,3-o-isopropylidenepropane to the corresponding diol, in order to obtain a furanic isoster of Propranolol (17a ), was unsuccessful.     

Synthesis,crystal structure and photoluminescence of 3-(4-(anthracen-10-yl)phenyl)-benzo[5,6]coumarin

A new coumarin derivative, 3-(4-(anthracen-10-yl)phenyl)-benzo[5,6]coumarin, was synthesized and characterized by FT-IR, ¹H NMR, element analysis and single crystal X-ray crystallography. The dihedral angle of benzo[5,6]coumarin ring and phenyl group is 36.15°, and the dihedral angle of phenyl group and anthracene skeleton is 89.37°. The UV–vis absorption and photoluminescence of the compound were discussed. The result shown that the compound exhibits high fluorescence quantum yield (Φ_F), large Stokes shift and green emission (508 nm). The molecular structure of the compound was optimized using density functional theory (DFT) at B3LYP/6-31G(d) level, and the HOMO and LUMO levels of the compound were deduced.     

Thermally-induced radical rearrangement of 2-(2-thienylmethoxy)-and 2-(2-benzo[b]thienylmethoxy)tropones

Upon heating at ca. 160°, 2-(2-thienylmethoxy)tropone afforded 3- and 5(2-thienylmethyl)tropolones. Formation of 3,5-bis(2-thienylmethyl)tropolone and unsubstituted tropolone indicated a radical chain mechanism for the thermolysis.