3-Amino-thieno[2,3-b]furane und 3-Amino-thieno[3,2-b]furane

3-Amino-thieno[2,3-b]furans and 3-Amino-thieno[3,2-b]furans The O-alkylation of 2-hydroxy-thiophene-3-carbonitriles ( 1 ) with α-bromocarbonyl compounds yields the 2-alkoxy-thiophene-3-carbonitriles ( 2a–f ) among them 2-benzoylmethoxy-thiophene-3-carbonitriles ( 2a–c ) which undergo Thorpe-Ziegler-cyclization to form the 3-amino-2-benzoyl-thieno[2,3–b]furans ( 3 ) in low yields. The 2-acyl-3-amino-thieno[3,2–b]furans and ethyl 3-amino-thieno[3,2–b]furan-2-carboxylates ( 6 ) are synthesized in similar manner from 3-hydroxy-thiophene-2-carbonitriles ( 4 ) and α-halogencarbonyl compounds via 3-acylmethoxy- and 3-ethoxycarbonylmethoxy-thiophene-2-carbonitriles ( 5 ) with high yields.     

Reactions with 5,6-Diphenyl-2,3-dihydro-imidazo[2,1-b]thiazol-3-ones and 6,7-Diphenyl-2,3-dihydro-4H-imidazo[2,1-b]1,3-thiazin-4-one

2-Methyl-5,6-diphenyl-2,3-dihydro-imidazo[2,1-b]thiazol-3-one 5 and 6,7-diphenyl-2,3-dihydro-4H-imidazo[2,1-b]1,3-thiazin-4-one 6 are prepared from 4,5-diphenyl-2-mercapto-imidazole 1 . Compounds 5 and 6 react with amines or hydrazines to give the 2-(4,5-diphenyl-imidazol-2-ylthio)acet(or propan) amides (hydrazides) 7a – g and the 3-(4,5-diphenyl-imidazol-2 ylthio) propanamides(hydrazides) 8a – e , respectively. The hydrazides 7a, 7b and 8a are condensed with aromatic aldehydes to the hydrazones 9a – h and 10a – d . Compound 5 couples with aryldiazonium salts to give 2-arylazo-2-methyl-5,6-diphenyl-2,3-dihydro-imidazo[2,1-b]thiazol-3-ones 11a – d .     

2-Arylamino-thiophen-3-carbonsäurederivate

2-Arylamino-thiophene-3-carboxylic Acid Derivatives The title compounds 3 are synthesized by reaction of 2-amino-thiophene-3-carboxylic acid derivatives 1 with anilines. The nucleophilic 5-position in 3 allowed the synthesis of 5-aryliden-Δ³-thiolen-2-one-imines 5 , 6 and the oxidative coupling to yield the azo compound 7 . 1-Aryl-thieno-[2,3-d]pyrimid-4-ones 9 , the thieno[2,3-b]chinolin-4-one 10 and the 4-chloro thieno[2,3-b]chinolines 10 , 11 can be obtained from 3 .     

2,3-Heterokondensierte Thiophene aus substituiertem 2-Aminothiophen-3-thiol

2,3-Heterocondensed Thiophenes from Substituted 2-Aminothiophen-3-thiole Ethyl 5-amino-4-mercapto-3-methyl-thiophen-2-carboxylate ( 2 ), obtainable from the appropriate thienylthiocyanate 1 by reduction, undergoes reactions in analogy to the 2-aminobenzenthiole. Thus, with formic acid or trimethylorthoacetat the thieno [2,3-d]thiazoles 4 and 5 are formed. Aromatic aldehydes yield the thieno[2,3-d]thiazolines ( 6 ) which can be dehydrogenated by sulphur to form 9 . From carbon disulfide and 2 the thieno[2,3-d]thiazol-2-thione ( 7 ) is formed. With phenacylbromide or ethyl bromoacetate 2 can be converted into the thieno[3,2-b] thiazine derivatives 11 or 12 . Diazotation of 2 yields the thieno[2,3-d]1,2,3-thiadiazole derivative ( 14 ).     

5,6,7-Trihydro-5,7-diphenyl-thiazolo[3,2-b]-s-triazin-3 (2h)-one as a stabilizer for the double base propellant

5,6,7-Trihydro-5,7-diphenyl-thiazolo [3,2-b]-s-triazin-3(2H)-one (C₁₇H₁₅N₃OS) is used as a stabilizer for the double base propellant and gave good results with the stability tests. The samples were stored for 12 days at 100° C and were extracted by different suitable solvents. The column partition chromatography helped in separation of 5,6,7-trihydro-5,7-(2-nitrodiphenyl)-thiazolo[3,2-b]-s-triazin-3(2H)-one; 5,6,7-trihydro- 5,7-(4-nitrodiphenyl)-thiazolo[3,2-b]-s-triazin-3(2H)-one; 5,6,7-trihydro-5,7-(2,2′-dinitrodiphenyl)-thiazolo[3,2-b]-s-triazin-3(2H)-one; 5,6,7-trihydro-5,7-(4,4′-dinitrodiphenyl)-thiazolo[3,2-b]-s-triazin-3 (2H)-one with their different percentages.     

A Novel and Expedient Approach to New Thiazoles, Thiazolo[3,2-a]pyridines, Dihydrothiophenes, and Hydrazones Incorporating Thieno[2,3-b]thiophene Moiety

This paper reports details about the synthesis of a series of novel functionalized symmetrical bis-heterocyclic compounds containing a thieno[2,3-b]thiophene motif. Bis-thiazole derivatives 2, 3a-c and thiazolo[3,2-a]pyridine derivatives 4a-c are achieved. The hitherto unknown dihydrothiophene derivatives 6a-dvia bis-pyridimium salt 5 are obtained. Additionally, the novel hydrazonothieno[2,3-b]thiophene derivatives 10a-c are obtained via bis-tosylacetylthieno[2,3-b]thiophene derivative 9. All compounds are characterized by (1)H-, (13)C-NMR, GCMS, IR, and UV-vis spectrometry. These compounds represent a new class of sulfur and nitrogen containing heterocycles that should also be of interest as new materials.     

Synthese von Pyrrolo[1,2-a]chinazolinonen,Indolo[1,2-a]chinazolinonen,Pyrrolo[1,2-a]thieno[3,2-e]pyrimidinonen,Benzothieno[3,2-e]-pyrrolo[1,2-a]pyrimidinonen und 6H-Cyclohepta[4,5]thieno-[3,2-e]pyrrolo[1,2-a]pyrimidinonen

A Synthesis of Pyrrolo[1,2-a]quinazolinones, Indolo[1,2-a]-quinazolinones, Pyrrolo[1,2-a]thieno[3,2-e]pyrimidinones, Benzothieno[3,2-e]pyrrolo[1,2-a]pyrimidinones and 6H-Cyclohepta[4,5]-thieno[3,2-e]pyrrolo[1,2-a]pyrimidinones α-Cyano-γ-halo-crotonnitriles ( 1 ) synthesized (e.g. via Knoevenagel reaction and by subsequent halogenation) react with primary arylamines ( 2 ) to substituted 1-aryl-2-amino-3-cyano-pyrroles ( 3 ). We found that the reaction yields pyrrolo[1,2-a]quinazolin-5-ones ( 6 ) in a one-pot procedure if anthranilic esters ( 4 ) and compounds of the general formula 5 are used. The analogous treatment with 2-amino-3-ethoxy-carbonyl-thiophene derivatives ( 8 ) leads to pyrrolo[1,2-a]thieno-[3,2-e]pyrimidin-5-ones, benzothieno[3,2-e]pyrrolo[1,2-a]pyrimidinones and 6H-Cyclohepta[4,5]-thieno[3,2-e]pyrrolo[1,2-a]pyrimidinones as thiadiazastereoid analogs 9 . This reaction is suitable for the synthesis of various heterocyclic ring systems.     

Synthesis of Thiazolo(4,5-b)-quinoxalines and related compounds

The reaction of 2,3,7-trichloroquinoxaline ( 1 ) or 2,3-dichloro-7-bromoquinoxaline ( 2 ) with thiourea in DMSO gave 6,6′-dichloro- or 6,6′-dibromodiquinoxalino[2,3-b:2′:3′-e]1,4-dithiien ( 3 or 4 ). However, 1 or 2 reacts with thiourea in ethanol to give ( 3 or 4 ) beside 7-chloro- or 7-bromo-2-imino-2,3-dihydrothiazolo[4,5-b] quinoxaline ( 5 or 6 ) respectively. Interaction of 1 or 2 with acetone thiosemicarbazone gave 7-chloro- or 7-bromo-3-amino-2-imino-2,3-dihydro-thiazolo[4,5-b] quinoxaline hydrochloride ( 13 or 14 ) respectively. Cyclization of 7-chloro- or 7-bromo-3-amino-2-imino-2,3-dihydrothiazolo[4,5-b]quinoxaline ( 15 or 16 ) on treatment with aromatic acid chlorides or isothiocyanates succeeded to give 19—21 or 28 and 29 .     

Zur Synthese und Abwandlung N-substituierter 2(1 H)-Pyrimidin-thione - Ein einfacher Zugang zu Pyrimidino[2,3-b]1,3,4-thiadiazoliumsalzen

Synthesis and Transformation of N-substituted 2(1 H)-Pyrimidine-thiones – A Simple Route to Pyrimidino [2,3-b]1,3,4-thiadiazolium Salts N-substituted 2(1 H)-pyrimidine-thiones 4–6 can be prepared by reaction of primary amines or unsubstituted or substituted hydrazines with 3-isothiocyanato-propene-(2)-iminium salts 2 , which are easily aviable from 3-chloro-propene-(2)-iminium salts 1 . The 2(1 H)-pyrimidine-thiones are transformed into 2-alkylmercapto-pyrimidinium salts 7 and pyrimidino[2,3-b]1,3,4-thiadiazolium salts 9 , respectively.     

Thieno[3,2-b]thiophene as π-bridge at different acceptor systems for electrochromic applications

Benzoselenadiazole, quinoxaline and thieno[3,2-b]thiophene are the units preferred in conducting polymers due to their electrochemical properties. There are no reports in the literature on polymers containing both moieties. In this study, novel benzoselenadiazole, quinoxaline and thieno[3,2-b]thiophene based monomers; 4-(3a,6a-dihydrothieno[3,2-b]thiophen-2-yl)-7-(thieno[3,2-b]thiophenyl)benzo[c][1,2,5]selenadiazole (BSeTT) and 2,3-bis(3,4-bis(decyloxy)phenyl)-5,8-dibromo-2,3-dihydroquinoxaline (QTT) were synthesized via Stille Coupling and polymerized electrochemically. These polymers were characterized in terms of their spectroelectrochemical and electrochemical properties by cyclic voltammetry and UV–Vis–NIR spectroscopy. Spectroelectrochemistry analysis of PBSeTT revealed an electronic transition at 525 nm corresponding to π–π* transition with a band gap of 0.93 eV whereas PQTT revealed electronic transitions at 440 and 600 nm corresponding to π–π* transitions with a band gap of 1.30 eV. Electrochromic investigations showed that PBSeTT has gray color PQTT switching between green and gray. Switching time of the polymers was evaluated by a kinetic study upon measuring the percent transmittance (%T) at the maximum contrast point.     

吡啶并吡嗪/咪唑杂环化合物的合成研究

以2,3-二氨基吡啶或2,3,5,6-四氨基吡啶盐酸盐等为原料合成了吡啶并吡嗪、吡啶并咪唑及吡啶并二咪唑氮杂环衍生物。探讨了反应条件对产物收率的影响,初步确定了优化反应条件。对2,3-二甲基吡啶并吡嗪及2,3-二乙基吡啶并吡嗪的合成,氯化铵-甲醇体系具有明显的催化效果。使用4,5-二羟基咪唑烷-2-酮代替乙二醛与2,3-二氨基吡啶反应,可显著提高吡啶并吡嗪的合成收率;对于吡啶并咪唑和2-甲基吡啶并咪唑的合成,以2,3-二氨基吡啶与原甲酸三乙酯或原乙酸三甲酯为原料,在磷钼酸催化下反应,收率达50%以上;对于吡啶并[2,3-b:5,6-b']二咪唑和2,6-二甲基吡啶并[2,3-b:5,6-b']二咪唑的合成,分别以2,3,5,6-四氨基吡啶盐酸盐与原甲酸三乙酯和原乙酸三甲酯为原料在磷钼酸催化下反应,收率可达68.7%和66.5%。     

6-甲基-4-羟基-噻嗯并[2,3-b]噻喃-2-磺酰胺的合成

以2-巯基噻吩和巴豆酸为起始原料,经加成缩合制得3-(2-噻吩巯基)丁酸;在P2O5催化下环合制得6-甲基-4-氧-噻嗯并[2,3-b]噻喃;再用氯磺酸进行氯磺化、氨水氨解制得6-甲基-4-氧-噻嗯并[2,3-b]噻喃-2-磺酰胺;最后用硼氢化钠还原得到盐酸杜塞酰胺的中间体6-甲基-4-羟基-噻嗯并[2,3-b]噻喃-2-磺酰胺,合成总收率为16.0%。其化学结构经IR,1H NMR,MS得以确证。     

Comprehensive and Facile Synthesis of Some Functionalized Bis-Heterocyclic Compounds Containing a Thieno[2,3-b]thiophene Motif

A comprehensive and facile method for the synthesis of new functionalized bis-heterocyclic compounds containing a thieno[2,3-b]thiophene motif is described. The hitherto unknown bis-pyrazolothieno[2,3-b]thiophene derivatives 2a-c, bis-pyridazin othieno[2,3-b]thiophene derivatives 4, bis-pyridinothieno[2,3-b]thiophene derivatives 6a,b, and to an analogous bis-pyridinothieno[2,3-b]thiophene nitrile derivatives 7 are obtained. Additionally, the novel bis-pyradazinonothieno[2,3-b]thiophene derivatives 9, and nicotinic acid derivatives 10, 11 are obtained via bis-dienamide 8. The structures of all newly synthesized compounds have been elucidated by (1)H, (13)C NMR, GCMS, and IR spectrometry. These compounds represent a new class of sulfur and Nitrogen containing heterocycles that should also be of interest as new materials.     

Novel Thienopyridines

A number of novel thieno[2,3-b]pyridines were prepared from the reaction of 1 with unsaturated haloalkanes, and by the reaction of the amino ketones 9 and 10 with DMF dimethylacetal or triethyl orthoformate. The synthesis of novel thieno[2,3-c] and [3,2-c] pyridines, and a thieno[2,3-b;4,5-b']dipyridine are also reported.     

Beiträge zum Reaktionsverhalten von Derivaten der Imidodithiokohlensäure. II [1]. 7-Hydroxythiazolo[4,5-b]pyridone-(5)

Contributions to the Reaction Behaviour of Derivatives of Imidodithiocarbonic Acid. II. 7-Hydroxythiazolo[4,5-b]pyrid-5-ones Derivatives of cyanimidocarbonic acid 1 react with ethyl γ-bromoacetoacetate to ethyl thiazolylacetates 2 which are converted into 7-hydroxythiazolo[4,5-b]pyrid-5-ones 3 by acid or base catalyzed cyclisation. These compounds can be alkylated as well as acylated. The 7-hydroxy group is exchangeable for chlorine. Furthermore in position 6 electrophilic sulfonation can take place.     

Novel derivatives of methyl hexahydro-3-methyl-6-thioxo-1,2,4,5-tetrazine-3-nonanoate

Methyl hexahydro-3-methyl-6-thioxo-1,2,4,5-tetrazine-3-nonanoate (I) on treatment with reagents such as chloroacetic acid, 1,2-dibromoethane and 2-mercaptoethanol under different reaction conditions afforded methyl 3,4,6,7-tetrahydro-3-methyl-6-oxo-2H-thiazolo[3,2-b]-1,2,4,5-tetrazine-3-nonanoate (II), methyl 3,4,6,7-tetrahydro-3-methyl-2H-thiazolo[3,2-b]-1,2,4,5-tetrazine-3-nonanoate (III) and methyl 8-methyl-1-oxa-4-thia-6,7,9,10-tetraazaspiro-[4.5]-decane-8-nonanoate (IV) in good yields. The structures of compounds II–IV were established by elemental analysis, infrared (IR), nuclear magnetic resonance (NMR), and mass spectral data.     

Cyclofunktionalisierung von 2-Allyl-phenolen mit Schwefelchloriden. III. 2-Arylthiomethyl-2,3-dihydrofuro[3,2-h]chinoline aus 7-Allyl- bzw. 7-Methallyl-8-hydroxychinolin und Aryl-sulfenylchloriden

Cyclofunctionalization of 2-Allyl-phenols with Sulfur Chlorides. III. 2-Arylthiomethyl-2,3-dihydrofuro[3,2-h] quinolins from 7-Allyl- and 7-Methallyl-8-hydroxyquinoline, respectively, and Arylsulfenyl Chlorides Reactions of 7-allyl- ( 3 ) and 7-methallyl-8-hydroxyquinoline ( 4 ) with selected arylsulfenyl chlorides ( 5a – d ) yield the products of cyclofunctionalization corresponding 2-arylthiomethyl-2,3-dihydrofuro[3,2-h]quinolins ( 6 and 7 ). The products are identified by ¹H-n.m.r.-spectroscopy, mass spectrometry and microanalyses.     

Amino-thieno[2,3–c]pyrazole und Amino-thieno[2,3–b]pyrrole

Amino-thieno[2,3–c]pyrazoles and Amino-thieno[2,3–b]pyrroles The synthesis of thieno[2,3–c]pyrazoles and thieno[2,3–b]pyrroles is described. From the dithioliumsalt ( 1 ) and potassium hydroxide the potassium-(2,2-dicyan-1-methylthio-ethen-1-yl)-thiolate ( 2 ) is formed. This reacts with hydrazine hydrate to form the 3-amino-5-thioxo-pyrazol-4-carbonitrile ( 3 ) S-Alkylation with α-chlorocarbonyl compounds yielding ( 6a–c ) leads via Thorpe-Ziegler-cyclization to 3,4-diamino-thieno[2,3–c]pyrazoles ( 9 ) if the position 1 is alkylated ( 8 ). Acetyl acetone yields 2-mercapto-pyrazolo[1,5–a]pyrimidine ( 5 ). After S-alkylation ( 10a–d ) are immediately cyclized to thieno [2′,3′:3,4]pyrazolo[1,5-a]pyrimidine ( 11a–d ). The ketone ( 6a ) can be cyclized to the pyrazolo [5,1–b]thiazole ( 12 ). 3 reacts with oxalyl chloride to form the 2,3-dioxo-6-thioxo-imidazo[1,2-b]pyrazole ( 13 ) of which S-phenacyl derivative ( 14 ) because the NH-proton cannot be cyclized. The 5-amino-3,4-dicyano-pyrrol-2-thiolate ( 16 ) shows the analogous behaviour. The S-alkylation is followed by cyclization, and 3,5-diamino-thieno[2,3–b]pyrroles ( 18a–b ) arise. Reaction of 5-amino-2-alkylthio-pyrrol-3,5-dicarbonitrile ( 17 ) with acetyl acetone provides pyrrolo[1,2-a]pyrimidine ( 20a–c ) which can be cyclized to form thieno[3′,2′:4,6]pyrimidines ( 21a–c ) very easily.     

5,6-二氢-4H-6-甲基噻嗯并[2,3-b]噻喃-4-酮-2-磺酰胺的合成

以丁烯酸和2-巯基噻吩为原料,经加成缩合制得3-(2-噻吩硫基)丁酸(2);以氯化亚砜氯化,三氯化铝催化环合得5,6-二氢-4H-6-甲基噻嗯并[2,3-b]噻喃-4-酮(3);再经磺化、氯化、氨解反应合成得5,6-二氢-4H-6-甲基噻嗯并[2,3-b]噻喃-4-酮-2-磺酰胺(1)。其中经均匀设计优化了环合反应条件为:n(2)∶n(氯化亚矾)∶n(三氯化铝)=1∶3∶1.5,于20℃反应2h。以2-巯基噻吩计,1合成总收率为30.49%,结构经IR、MS、1HNMR确证。     

Quinoxaline derivatives as long wavelength photosensitizers in photoinitiated cationic polymerization of diaryliodonium salts

The present paper is focused on visible light initiated cationic polymerizations. Photoinitiated polymerization of representative vinyl ether and oxirane monomers using two quinoxaline derivatives; namely (2-(2,3-dihydrobenzo [b][1,4]dioxin-6-yl)-3-(2,3-dihydrobenzo[b]-[1,4]dioxin-7-yl)-5-(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-8-(2,3-dihydrothieno[3,4-b][1,4]dioxin-7yl) quinoxaline) (DBQEd) and 2,3,5,8-tetra(thiophen-2-yl)quinoxaline (TTQ) are studied. Novel dyes based on the quinoxaline skeleton are employed as efficient photosensitizers in cationic photopolymerizations. Polymerizations were initiated at room temperature upon irradiation with long-wavelength UV and visible lights in the presence of diphenyliodonium hexafluorophosphate (Ph₂I⁺PF₆^?). The progress of the polymerizations was monitored by optical pyrometry (OP). Solar irradiation is also employed to carry out the cationic polymerization of a diepoxide monomer in the presence of air.