1,3,4-Thiadiazoles and 1,3-thiazoles from one-pot reaction of bisthioureas with 2-(bis(methylthio)methylene)malononitrile and ethyl 2-cyano-3,3-bis(methylthio)acrylate

Bisthioureas reacted with either 2-(bis(methylthio)methylene)malononitrile or ethyl 2-cyano-3,3-bis(methylthio)acrylate to give 1,3,4-thiadiazoles and 1,3-thiazoles. Only, the reactive allyl derivative of bisthioureas reacted with the bis(methylthio)methylene compounds to give 1,3-thiazoles. The mechanism was discussed. The structures of products were proved by MS, IR, NMR and elemental analyses and X-ray structure analysis.     

Push-pull-Butadiene. VIII. Reaktionen von substituierten Penta-1,4-dien-1,1,5,5-tetracarbonitrilen

Push-pull-Butadienes. VIII. Reactions of Substituted 1,4-Pentadiene-1,1,5,5-tetracarbonitriles 4-Aryl-2-methylthio-1,4-pentadiene-1,1,5,5-tetracarbonitriles 1 react with bromine to give the nicotinonitriles 2 . Compounds 2 and hydrazine hydrate yield the pyrazolo[3,4-b]-pyridines 7 . Bis(methylthio)nicotinonitriles 9 are prepared by the treating of 2 with methanethiol in an alkaline solution. Compounds 1 can be converted with hydrobromic acid or hydrochloric acid to the nicotinonitriles 2a--c and 2d--f , respectively.     

Ring transformation and cyclization reactions of 1,1-dioxo-1,2-thiazines – syntheses of pyridines and benzo[c]thiazines with new substitution pattern

In presence of ammonia/ammonium acetate the 3,5-dimethyl-2-phenyl-1,1-dioxo-1,2-thiazine-4-carbaldehyde ( 1 ) reacts with ethyl cyanoacetate to the ethyl 2-cyano-4-[1-methyl-2-methylthio-2-(N-phenylsulfamoyl)vinyl)-hexa-2,4-dienoate] ( 3 ) and the Knoevenagel condensation product 4-(2-ethoxycarbonyl-2-cyanovinyl)-3,5-dimethyl-6-methylthio-1,1-dioxo-2-phenyl-2H-1,2-thiazine ( 2 a). The 4-(2,2-dicyanovinyl)-3,5-dimethyl-6-methylthio-1,1-dioxo-2-phenyl-2H-1,2-thiazine ( 2b ) is obtained from 1 and malononitril. The masked 1,5-dicarbonyl compound 2a undergoes ring transformation to the 3-cyano-1,6-dimethyl-5-[1-methylthio-2-(N-phenylsulfamoyl)vinyl]pyridin-2-one ( 5 ) with methylamine. With ethanolic ethoxide the condensation products 2a,b afford the 7-amino-6-ethoxycarbonyl-4-methylthio-2,2-dioxo-1-phenyl-benzo[c]1,2-thiazine ( 6a ), respectively the corresponding 6-cyano derivative 6b , while 3 cyclizises to furnish ethyl 2-amino-6-methyl-5-[1-methyl-2-methylthio-2-(N-phenyl-sulfamoyl)vinyl]nicotinate ( 4 ).     

Acetals and Ethers. XVIII. Reaction products of prop-2-enal and but-2-enal with mixture: n-Aliphatic alcohol and ethylene glycol

The direct condensation reaction of prop-2-enal or but-2-enal with mixture of n-aliphatic alcohol and ethylene glycol, in the presence of p-toluenesulphonic acid as catalyst, leads to a complex mixture of saturated, unsaturated, cyclic and linear acetals, moreover, 2-(2-alkoxy-alkyl)-1,3-dioxolanes are the main reaction products. The detailed investigations for n-butanol showed that unsaturated cyclic acetals: 2-vinyl-1,2-dioxolane 1a or 2-(1-propenyl)-1,3-dioxolane 1b , as well as unsaturated linear acetals: 1,1-dibutoxy-prop-2-en 2a or 1,1-dibutoxy-but-2-en 2b are intermediate reaction products. Additionally, it was found in final products presence of eight by-products: 5-butoxy- 4a or 5-butoxy-7-methyl-1,4-dioxepane 4b , 1,1,3-tributoxypropane 5a or 1,1,3-tributoxybutane 5b , 2-[2-(2-hydroxyethoxy)ethyl]- 6a or 2-[2-(2-hydroxyethoxy)propyl]-1,3-dioxolane 6b , 5-(2-hydroxyethoxy)-7-methyl-1,4-dioxepane 7b , 1,3-dibutoxy-1-(2-hydroxyethoxy)-propane 8a or 1,3-dibutoxy-1-(2-hydroxyethoxy)-butane 8b , 1,1-dibutoxy-3-(2-hydroxyethoxy)-propane 9a or 1,1-dibutoxy-3-(2-hydroxyethoxy)-butane 9b , 3-butoxy-1,1-bis-(2-hydroxyethoxy)-propane 10a or 3-butoxy-1,1-bis-(2-hydroxyethoxy)-butane 10b , and 1-butoxy-1,3-bis-(2-hydroxyethoxy)-propane 11a or 1-butoxy-1,3-bis-(2-hydroxyethoxy)-butane 11b , respectively.     

Synthese und Polymerisation von 2-Aryl-5-methylen-1,3-dioxolan-4-onen und Arylbis(5-methylen-1,3-dioxolan-2-yl-4-on)en

Synthesis and Polymerization Behaviour of 2-Aryl-5-methylene-1,3-dioxolan-4-ones and Arylbis(5-methylene-1,3-dioxolan-2-yl-4-on)es Starting from 2,6-di(hydroxymethyl)-4-methylphen-ol-Na-salt-1-hydrate ( 1 ) a synthesis of 2-alkoxy-5-methyliso-phthaldialdehydes ( 3a,b ) is described via alkylation and oxidation. Condensation of aromatic aldehydes with 3-bromo-2-hydroxypropanoic acid (β-bromolactic acid) affords diastereoisomeric mixtures of new 2-aryl-5-bromomethyl-1,3-dioxolan-4-ones ( 6a–h ) as well as the corresponding bisdioxolanones ( 6i–l ). Dehydrobromination of 2-aryl-5-bromomethyl-1,3-dioxolan-4-ones ( 6a–d,i ) with DBU leads to 2-aryl-5-methylene-1,3-dioxolan-4-ones ( 8a–e ). Polymerization of compounds 8a , b , d and e proceed via opening of the dioxolanone ring.     

Tetrazolverbindungen. 2. (1-Aryl-1H-tetrazol-5-yl)-acetaldehyd-Derivate aus 1-Aryl-5-(2-dimethylamino-vinyl)-1H-tetrazolen

Tetrazole Compounds. 2. 1-Aryl-1H-tetrazole-5-acetaldehyde Derivatives from 1-Aryl-5-(2-dimethylamino-vinyl)-1H-tetrazoles 1-Aryl-5-(2-dialkylamino-vinyl)-1H-tetrazoles 2 , easily accessible by the reaction of 3-chloro-propeniminium salts 1 with excess sodium azide in refluxing alcohols, represent enamines of the hitherto unknown 1-aryl-1H-tetrazole-5-acetaldehydes 3 . Attempts to isolate the latter after acid-catalyzed hydrolysis of 2 were unsuccessful. However, generated in situ, they can be trapped by suitable aldehyde reagents. Thus, starting from 1-aryl-5-(2-dimethylamino-vinyl)-1H-tetrazoles 4 , the 4-nitrophenylhydrazones 5a--hyphen;i , 2,4-dinitrophenylhydrazones 5j--hyphen;r , and thiosemicarbazones 6 of the corresponding 1-aryl-1H-tetrazole-5-acetaldehydes 3 were obtained. Analogously, acid-catalyzed hydrolysis of 4 in the presence of 1,2-dianilinoethane resulted in 1-aryl-5-(1,3-diphenyl-2-imidazolidinylmethyl)-1H-tetrazoles 7 . --hyphen; The structure of the aldehyde derivatives 5 , 6 , and 7 was proved by ¹H n.m.r. spectroscopy.     

Synthesis and characterization of polyphenylene vinylenes having <Emphasis Type="Italic">m</Emphasis>-terphenyl group: comparison of their optical properties

A series of alternate block copolymers of polyphenylene vinylenes that have 1,3-dioctyloxy phenylene in the center of kinked m-terphenyl group as one of the building blocks with either one of the aromatic groups, viz., 1,4-dioctyloxy benzene, 4,6-dioctyloxy benzene and 4,4′-dioctyloxy biphenyl, was synthesized through Heck polymerization. These alternate block copolymers, viz., poly(2,5-bis(octyloxy)phenylene vinylene alt 4′,6′-bis(octyloxy)-1,1′:3′,1″-terphenylene) (P1), poly(2,4-bis(octyloxy)phenylene vinylene alt 4′,6′-bis(octyloxy)-1,1′:3′,1″-terphenylene) (P2) and poly(4,4′-bis(octyloxy-3,3′-biphenylene vinylene alt 4′,6′-bis(octyloxy)-1,1′:3′,1″-terphenylene) (P3), were characterized for their thermal and optical properties. The synthesized polymers had good solubility in organic solvents and were stable up to 350 °C. The molecular weights of the synthesized polymers were in the range 4370–10,900 Da with polydispersity range 1.52–1.65, which were measured by the gel permeation chromatography technique. The optical properties of these polymers showed absorptions in solution at around 400, 329, and 345 nm for P1, P2, and P3 polymers, respectively. The photoluminescence emission maxima of the polymers were at around 461 nm with a shoulder 439 and 424 nm for P1, P2, and P3, respectively. Photoluminescence emission of films of these polymers showed minimum redshift (20 nm) when compared with spectra of their solutions. The optical and photoluminescence emission properties of these polymers were found to vary on the backbone structure.     

N-(6-氯-4-甲硫基-1-羰基异色烷-5-基)-三氟乙酰胺的合成

对一种吲哚化合物的关键中间体———N-(6-氯-4-甲硫基-1-羰基异色烷-5-基)-三氟乙酰胺的合成进行了研究。以2-氯乙醇为原料,经甲硫醇钠的亲核取代和特戊酰氯的酯化反应,生成2-(甲硫基)乙基特戊酸酯,产率92.2%。以3-氨基-4-氯苯甲酸为原料,经酯化反应生成3-氨基-4-氯苯甲酸甲酯,产率80.0%。所得中间体2-(甲硫基)乙基特戊酸酯低温下经磺酰氯氧化,与中间体3-氨基-4-氯苯甲酸甲酯反应,所得产物经重排、水解和酰化反应得到目标化合物,总产率25.8%。     

Gemini Pyridinium Surfactants: Synthesis and Their Surface Active Properties

New pyridinium Gemini surfactants have been synthesized by esterification of renewable fatty acids with halogenated alcohols furnishing respective esters (2‐chloroethyl hexadecanoate, 2‐chloroethyl tetradecanoate, 2‐chloroethyl dodecanoate, 2‐bromoethyl hexadecanoate, 2‐bromoethyl tetradecanoate and 2‐bromoethyl dodecanoate) followed by their subsequent treatment with 4,4′‐trimethylenedipyridine resulting into the formation of title Gemini surfactants: (4,4′‐(propane‐1,3‐diyl)bis(1‐(2‐(hexadecanoyl oxy) ethyl) dipyridinium chloride(7), (4,4′‐(propane‐1,3‐diyl)bis(1‐(2‐(tetradecanoyl oxy) ethyl) dipyridinium chloride (8), 4,4′‐(propane‐1,3‐diyl)bis(1‐(2‐(dodecanoyl oxy) ethyl) dipyridinium chloride (9), (4,4′‐(propane‐1,3‐diyl)bis(1‐(2‐(hexadecanoyl oxy) ethyl) dipyridinium bromide (10), (4,4′‐(propane‐1,3‐diyl)bis(1‐(2‐(tetradecanoyl oxy) ethyl) dipyridinium bromide (11), 4,4′‐(propane‐1,3‐diyl)bis(1‐(2‐(dodecanoyl oxy) ethyl) dipyridinium bromide (12). Their identifications are based on IR, ¹H‐, ¹³C‐NMR, DEPT, COSY and mass spectral studies. Their surface active properties are also evaluated on the basis of surface tension and conductivity measurements and thermal stability of these long chain cationics Gemini surfactants have been measured by thermal gravimetric analysis under nitrogen atmosphere.     

Action of Grignard Reagents on 6-Arylpyridazin-3(2H)-thiones

6-Arylpyridazin-3(2H)-thiones ( 1a—c ) react with Grignard reagents by 1,4-addition to give either 4-substituted 6-aryl-4,5-dihydropyridazin-3(2H)-thiones ( 2a—c ) or their dehydrogenated products, namely 4-substituted 6-arylpyridazin-3(2H)-thiones ( 3d—k ). The reaction of Grignard reagents with 6-aryl-4-methylpyridazin-3(2H)-thiones ( 3d—f ) proceeds also by 1,4-addition yielding 4,4-disubstituted 6-aryl-4,5-dihydropyridazin-3(2H)-thiones ( 5 ). Structural assignments are based on analytical and spectral data and also on the synthesis of authentic samples in some cases.     

The preparation of α‐bis and α,ω‐tetrakis aromatic oxazolyl‐ and carboxyl‐functionalized polymers using 1,1‐bis[4‐(2‐(4,4‐dimethyl‐1,3‐oxazolyl))phenyl]ethylene in atom transfer radical polymerization reactions

The preparation of new compounds, 1,1‐bis[4‐(2‐(4,4‐dimethyl‐1,3‐oxazolyl))phenyl]ethanol and a new symmetrically disubstituted 1,1‐diphenylethylene derivative, 1,1‐bis[4‐(2‐(4,4‐dimethyl‐1,3‐oxazolyl))phenyl]ethylene, is described. 1,1‐Bis[4‐(2‐(4,4‐dimethyl‐1,3‐oxazolyl))phenyl]ethylene was utilized as a dioxazolyl initiator precursor for the polymerization of styrene by atom transfer radical polymerization (ATRP) methods to produce α‐bis(oxazolyl) polystyrene. The kinetic study of the polymerization process indicated that the free radical polymerization reaction for the preparation of α‐bis(oxazolyl) polystyrene follows first‐order rate kinetics with respect to monomer consumption. α,ω‐Tetrakis(oxazolyl) polystyrene was prepared by a new, in situ, controlled/living, post‐ATRP chain‐end‐functionalization reaction which involves the direct addition of 1,1‐bis[4‐(2‐(4,4‐dimethyl‐1,3‐oxazolyl))phenyl]ethylene to the ω‐terminus of the α‐bis(oxazolyl) polystyrene derivative, without the isolation and purification of the polymeric precursor. α‐Bis(carboxyl) and α,ω‐tetrakis(carboxyl) polystyrene derivatives were obtained by the quantitative chemical transformation of the oxazoline groups of the respective aromatic oxazolyl chain‐end‐functionalized polystyrene derivatives to the aromatic carboxyl groups. The organic precursor compounds, the dioxazolyl‐functionalized 1,1‐diphenylethylene derivative and the functionalized polymers were characterized using ¹H NMR and ¹³C NMR spectrometry and Fourier transform infrared spectroscopy, size‐exclusion and thin‐layer chromatography and non‐aqueous titration measurements. © 2014 Society of Chemical Industry     

1,2,3-Triazabutadiene. XIII. UV-vis-spektroskopische Untersuchungen zur Protonierung Z-E-isomerer 1-Aryl-3-[3-methylbenzthiazolinyliden-(2)]- und 1-Aryl-3-[1,3-dimethylbenzimidazolinyliden-(2)]-triazene

1,2,3-Triazabutadienes. XIII. U.V.-vis-Spectroscopic Investigations of the Protonation of Z-E-Isomeric 1-Aryl-3-[3-methylbenzthiazolinyliden-(2)]- and 1-Aryl-3-[1,3-dimethylbenzimidazolinyliden-(2)]-triazenes The u.v.-vis absorption spectra of Z-E-isomeric 1-aryl-3-[3-methylbenzthiazolinyliden-(2)]- and 1-aryl-3-[1,3-dimethyl-benzimidazolinyliden-(2)]-triazenes 1–3 resp. 4 show a pronounced halochromic effect in the presence of acids. The reason is the protonation of the N¹-atom of the triazabutadiene chain whereby the energetically favourable structure of a diazatrimethine is formed. The magnitude of the halochromic effect depends on the substituents in the aryl and benzo residue and on the Z-E-structure of the compounds.     

Synthesis and Properties of Stannole-Containing Polymers by Reaction of Bis(cyclopentadienyl)titanacyclopentadiene-Containing Polymers and Tin(IV) Chloride

Polymers having bis(cyclopentadienyl)titanacyclopentadiene units in the main chain were prepared by the polymerization of a low-valent bis(cyclopentadienyl)-titanium(II) complex, generated in situ from bis(cyclopentadienyl)titanium dichloride (Cp₂TiCl₂) and n-butyllithium (2 equiv), with internal diynes such as 1,4-bis(1-hexynyl)-benzene and 4,4′-bis(1-hexynyl)biphenyl. The bis(cyclopentadienyl)titanacyclopentadiene-containing polymers were subjected to the reaction with tin(IV) chloride, followed by the treatment with methyllithium to give 1,1-dimethylstannole-containing organometallic polymers in moderate yields. The stannole containing polymers are soluble in organic solvents, whose number-average molecular weight was estimated to be 2,700–2,800 by GPC. Optical and electrochemical properties of the resulting stannole-containing polymers were studied by their UV-vis spectra and cyclic voltammetric analyses, from which they were supposed to have low LUMO energy levels.     

1,1-二甲硫基-2-硝基乙烯的合成

研究了以硝基甲烷和二硫化碳为原料,合成1,1-二甲硫基-2-硝基乙烯。考察了反应温度、反应时间、甲基化试剂、溶剂、投料比等对于反应产物的影响,得到优化工艺条件为:反应温度35℃,反应时间3h。以硫酸二甲酯为甲基化试剂,常温下反应时间3 h,重结晶得1,1-二甲硫基-2-硝基乙烯,收率为84%,产物通过IR、1H-NMR鉴定。     

Darstellung von 1-Cyan-4-dimethylamino-3-(pyrid-4-yl)-buta-1,3-dien-1-carbonsäure-Derivaten und ihre Cyclisierung zu 3-substituierten 2-Amino-5-(pyrid-4-yl)-pyridinen sowie den entsprechenden 1-Oxiden

Synthesis of 1-Cyano-4-dimethylamino-3-(4-pyridinyl)-1,3-butadiene-1-carboxylic Acid Derivatives and Their Cyclisation to 3-Substituted 2-Amino-5-(4-pyridinyl)-pyridines Including the Corresponding 1-Oxides The vinylogous amidinium salt 1 is transformed to 1-cyano-4-dimethylamino-3-(4-pyridinyl)-1,3-butadiene-1-carboxylic acid derivatives 3a - f by reaction with the cyanoacetic acid compounds 2a - f in the presence of bases. Treatment of the 3a - f with ammonia and hydroxylamine yields the 2-amino-5-(4-pyridinyl)-pyridine-3-carboxylic acid derivatives 5a - f and the corresponding 1-oxides 6a - f , respectively. The products 5d , e are also prepared via the 6d , e by reduction with phosphorus trichloride.     

Recent Developments in Enantioselective Metal‐Catalyzed Domino Reactions

Since the first definition of domino reactions by Tietze in 1993, an explosive number of these fascinating reactions has been developed, allowing the easily building of complex chiral molecular architectures from simple materials to be achieved in a single step. Even more interesting, the possibility to join two or more reactions in one asymmetric domino process catalyzed by chiral metal catalysts has rapidly become one challenging goal for chemists, due to economical advantages, such as avoiding costly protecting groups and time‐consuming purification procedures after each step. The explosive development of enantioselective metal‐catalyzed domino including multicomponent reactions is a consequence of the considerable impact of the advent of asymmetric transition metal catalysis. This review aims to update the last developments of enantioselective one‐, two‐ and multicomponent domino reactions mediated by chiral metal catalysts, covering the literature since the beginning of 2006. Abbreviations: Ac: acetyl; AQN: anthraquinone; Ar: aryl; bdpp: 2,4‐bis(diphenylphosphino)pentane; BINAP: 2,2′‐bis(diphenylphosphino)‐1,1′‐binaphthyl; BINEPINE: phenylbinaphthophosphepine; BINIM: binapthyldiimine; BINOL: 1,1′‐bi‐2‐naphthol; BIPHEP: 2,2′‐bis(diphenylphosphino)‐1,1′‐biphenyl; Bn: benzyl; Boc: tert‐butoxycarbonyl; Box: bisoxazoline; BOXAX: 2,2′‐bis(oxazolyl)‐1,1′‐binaphthyl; BPTV: N‐benzene‐fused phthaloyl‐valine; Bu: butyl; Bz: benzoyl; Cat: catechol; Chiraphos: 2,3‐bis(diphenylphosphine)butane; cod: cyclooctadiene; Cy: cyclohexyl; DABCO: 1,4‐diazabicyclo[2.2.2]octane; dba: (E,E)‐dibenzylideneacetone; DBU: 1,8‐diazabicyclo[5.4.0]undec‐7‐ene; DCE: dichloroethane; de: diastereomeric excess; DHQ: hydroquinine; DHQD: dihydroquinidine; DIFLUORPHOS: 5,5′‐bis(diphenylphosphino)‐2,2,2′,2′‐tetrafluoro‐4,4′‐bi‐1,3‐benzodioxole; DIPEA: diisopropylethylamine; DMF: dimethylformamide; DMSO: dimethyl sulfoxide; DOSP: N‐p‐dodecylbenzenesulfonylprolinate; DPEN: 1,2‐diphenylethylenediamine; dtb: di‐tert‐butyl; dtbm: di‐tert‐butylmethoxy; E: electrophile; ee: enantiomeric excess; Et: ethyl; FBIP: ferrocene bis‐imidazoline bis‐palladacycle; Fc: ferrocenyl; FOXAP: ferrocenyloxazolinylphosphine; Hex: hexyl; HFIP: hexafluoroisopropyl alcohol; HMPA: hexamethylphosphoramide; iPr‐DuPhos: 1,2‐bis(2,5‐diisopropylphospholano)benzene; Josiphos: 1‐[2‐(diphenylphosphino)ferrocenyl]ethyldicyclohexylphosphine ethanol adduct; L: ligand; MCPBA: 3‐chloroperoxybenzoic acid; Me: methyl; Me‐DuPhos: 1,2‐bis(2,5‐dimethylphospholano)benzene; MEDAM: bis(dimethylanisyl)methyl; MOM: methoxymethyl; Naph: naphthyl; NMI: N‐methylimidazole; MWI: microwave irradiation; Norphos: 2,3‐bis(diphenylphosphino)‐bicyclo[2.2.1]hept‐5‐ene; Ns: nosyl (4‐nitrobenzene sulfonyl); Nu: nucleophile; Oct: octyl; Pent: pentyl; Ph: phenyl; PHAL: 1,4‐phthalazinediyl; Pin: pinacolato; PINAP: 4‐[2‐(diphenylphosphino)‐1‐naphthalenyl]‐N‐[1‐phenylethyl]‐1‐phthalazinamine; Pr: propyl; Py: pyridyl; PYBOX: 2,6‐bis(2‐oxazolyl)pyridine; QUINAP: 1‐(2‐diphenylphosphino‐1‐naphthyl)isoquinoline; QUOX: quinoline‐oxazoline; Segphos: 5,5′‐bis(diphenylphosphino)‐4,4′‐bi‐1,3‐benzodioxole; Solphos: 7,7′‐bis(diphenylphosphino)‐3,3′,4,4′‐tetrahydro‐4,4′‐dimethyl‐8,8′‐bis‐2H‐1,4‐benzoxazine; SPRIX: spirobis(isoxazoline); SYNPHOS: 6,6′‐bis(diphenylphosphino)‐2,2′,3,3′‐tetrahydro‐5,5′‐bi‐1,4‐benzodioxin; Taniaphos: [2‐diphenylphosphinoferrocenyl](N,N‐dimethylamino)(2‐diphenylphosphinophenyl)methane; TBS: tert‐butyldimethylsilyl; TC: thiophene carboxylate; TCPTTL: N‐tetrachlorophthaloyl‐tert‐leucinate; TEA: triethylamine; Tf: trifluoromethanesulfonyl; TFA: trifluoroacetic acid; THF: tetrahydrofuran; TMS: trimethylsilyl; Tol: tolyl; Ts: 4‐toluenesulfonyl (tosyl); C₃‐Tunephos: 1,13‐bis(diphenylphosphino)‐7,8‐dihydro‐6H‐dibenzo[f,h][1,5]dioxonin; VAPOL: 2,2′‐diphenyl‐[3,3′‐biphenanthrene]‐4,4′‐diol     

Low-dielectric-constant aromatic homopolyimide and copolyimide derived from pyromellitic dianhydride, 4,4′-oxydianiline, 2,2-bis[4-(4-aminephenoxy)phenyl]propane, 1,4-bis(4-aminophenoxy)benzene,or 1,3-bis(4-aminophenoxy)benzene

Low-dielectric-constant aromatics, homopolyimide and copolyimide, were introduced. Homopolyimides were prepared by pyromellitic dianhydride (PMDA) as an anhydride monomer and 4,4′-oxydianiline (ODA), 2,2-bis[4-(4-aminephenoxy)phenyl]propane, 1,4-bis(4-aminophenoxy)benzene, or 1,3-bis(4-aminophenoxy)benzene as an amine monomer. The copolyimides were prepared with PMDA as an anhydride monomer, ODA as an amine monomer with the addition of 2,2-bis[4-(4-aminephenoxy)phenyl]propane, 1,4-bis(4-aminophenoxy)benzene, or 1,3-bis(4-aminophenoxy)benzene as another amine monomer. The polyimides were well characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, thermomechanical analysis, dielectric measurements, and tensile testing. The homopolyimide and copolyimides showed lower dielectric constants than the homopolyimide formed by ODA and PMDA. The results also indicate that the interchain distance, the quantities of phenyl ether, and the position of the substitute are factors that not only affected the thermal performance of polyimide by improving the molecular flexibility but also reduced the dielectric constant of polyimide by increasing the free volume of the molecular chain and decreasing the polarization points per unit volume. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47405.     

Preparation and characterization of organosoluble polyimides based on 1,1-bis[4-(3,4-aminophenoxy)phenyl]cyclohexane and commercial aromatic dianhydrides

A bis(ether amine) III-A containing a cyclohexane cardo group, 1,1-bis[4-(4-aminophenoxy)phenyl]cyclohexane, was synthesized and used as a monomer to prepare polyimides VI-A with six commercial dianhydrides via three different procedures. The intermediate poly(amic acid)s had inherent viscosities of 0.83–1.69 dL g⁻¹ and were thermally or chemically converted into polyimides. Polyimides were also prepared by high-temperature direct polymerization in m-cresol and had inherent viscosities higher than the thermally or chemically cyclodehydrated ones. To improve the solubility of polyimides, six copolyimides were also synthesized from bis(ether amine) III-A with a pair of dianhydrides, which contained 3,3′,4,4′-diphenylsulfonetetracarboxylic dianhydride or 4,4′-hexafluoroisopropylidenediphthalic anhydride. Series VI-A polyimides were characterized by the good physical properties of their film-forming ability, thermal stability, and tensile properties. A comparative study of the properties, with the corresponding polyimides derived from 2,2-bis[4-(4-aminophenoxy)phenyl]propane, is also presented. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2750–2759, 2001     

New positive-type photosensitive polyimide having sulfo groups

A new positive-working photosensitive polyimide (PSPI) has been developed, which is based on polyimide bearing sulfo groups (PIS) and 1-{1,1-bis[4-(2-diazo-1-(2H)naphthalenone-5-sulfonyloxy)phenyl]ethyl}-4-{1-[4-(2-diazo-1(2H)naphthalenone-5-sulfonyloxy)phenyl]methylethyl}benzene (S-DNQ) as a photosensitive compound. PIS was prepared by ring-opening polyaddition of 1,3-phenylenediamine-4-sulfonicacid (PDAS), 4,4′-oxydianiline (ODA), and 4,4′-hexafluoropropylidenebis(phthalic anhydride) (6FDA), followed by thermal cyclization in m-cresol. PIS containing 30 wt% of S-DNQ showed a sensitivity of 100 mJ cm⁻² and a contrast of 1.7, when it was exposed to 365 nm light followed by developing with 2.38 wt% aqueous tetramethylammonium hydroxide (TMAH) solution at room temperature. A fine positive image featuring 10 μm line and space patterns was observed on the film of the photoresist exposed to 200 mJ cm⁻² of UV-light at 365 nm by the contact mode. The positive image was successfully converted to the polyimide pattern by thermal treatment.     

Synthesis,spectral characteristics and structure of 1,3- and 1,4-disubstituted tetrazolinones

Reaction of ethylene oxide with 1-alkyl- or 1-aryl-1,4-dihydrotetrazole-5-thiones in acetic acid affords the corresponding mesoionic 1-alkyl- or 1-aryl-3-(2-hydroxyethyl)-tetrazolium-5-olates 4–6 . The X-ray structure of one of these compounds (5) is presented. On the other hand, the reaction of tetrazolinones with 2-chloroethanol in the presence of potassium hydroxide affords a mixture of the corresponding 1,3- and 1,4-disubstituted isomers. The isomers can be distinguished easily by their IR, ¹H or ¹³C NMR spectra. The fragmentation of these compounds in the mass spectrometer is discussed.