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An interesting protocol for the synthesis of benzothiadiazine-1,1-dioxides through iodine-catalyzed one-pot dehomologative oxidation of styrenes and readily available 2-aminobenzenesulfonamide has been developed. Diverse benzothiadiazine-1,1-dioxides were prepared using I2 as a catalyst, TBHP as an oxidant and Na2CO3 as a base. This reliable, metal and ligand free conversion involves dehomologation of styrene to aromatic aldehyde which on subsequent cyclisation affords benzothiadiazine-1,1-dioxides in good yield.

In Aerospace and Automobile sector weight plays significant role. The reason behind this is efficient & effective working of aircraft and motor vehicles. It also needs the high strength to weight ratio. This requirement is fulfilled by the composite materials. In this research, CLARE is a hybrid composite consisting of thin aluminium, carbon fiber & epoxy layer is found to be alternate for GLARE materials consisting of thin aluminium, glass fiber, & epoxy layer, have been using over 36 years for wide range of advance aerospace structural applications but having comparatively more weight than CLARE. CLARE laminates offer a distinctive amalgamation of properties such as outstanding fatigue resistance, high specific static properties, exceptional impact resistance, high strength to weight ratio, corrosion resistance, Stiffness and ease of manufacture and repair. But the delaminating occurs in the sheets of aluminum in GLARE material is eliminate by CLARE material Solicitation of CLARE materials for the skin or the outer parts here presented the need of CLARE materials in supportive structural members; the present work focuses on the fabrication various structural cross sections of Clare material. For fabrication purpose selected method is hand lay-up. Static & dynamic analysis of these Clare material cross sections was carried out; it follows a comparative study with the aluminium cross sections gives that the Clare has a better performance.

Now a day’s weight plays a very important role in aircraft industries. The reason behind this is efficient & effective working of aircraft. It also needs the high strength to weight ratio. This requirement is fulfilled by the composites. In this research, GLARE is a hybrid composite consisting of thin aluminum, glass fiber & epoxy layer. GLARE materials have been using over 36 years for wide range of advance aerospace structural applications. GLARE laminates offer a distinctive amalgamation of properties such as outstanding fatigue resistance, high specific static properties, exceptional impact resistance, good flame resistance, corrosion resistance and ease of manufacture and repair. But the delaminating occurs in the sheets of aluminum and similarly aluminum wire mesh is used. Solicitation of GLARE materials for the skin or the outer parts here presented the need of GLARE materials in supportive structural members; the present work focuses on the fabrication various structural cross sections of glare material. For fabrication purpose, selected method is hand lay-up. Static & dynamic analysis of these glare material cross sections was carried out; it follows a comparative study with the aluminum cross sections gives that the glare has a better performance.

Novel photoluminescent donor–acceptor poly(p-phenylenevinylene)-type conjugated polymers containing thiophene and 1,3,4-thiadiazole units in the main chain were synthesized from 2,5-bis(5-bromomethyl-2-thienyl)-1,3,4-thiadiazole and 1,3/1,4-benzenedialdehyde by Wittig–Horner reaction. The synthesized polymers were characterized by the use of thermal analysis and spectroscopic (infrared, UV-visible absorption, and photoluminescence) measurement. The resultant material exhibited bluish green, green, and orange fluorescence in their solution and thin film and solid forms, respectively. The redox property of the polymers has also been studied by cyclic voltammetry. The optical and electrochemical studies reveal that these novel polymers are new promising materials for the development of efficient polymer light-emitting diodes. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Four new aromatic polyamides containing pendant groups were synthesized by low temperature interfacial polycondensation of two asymmetrically substituted diamine monomers, namely, 4-[4-(1-methyl-1-phenylethyl) phenoxy]-1,3-diamino benzene and 4-{4-[(4-methylphenyl) sulphonyl]phenoxy}-1,3-diamino benzene with two aromatic diacid chlorides, namely isophthaloyl chloride and terephthaloyl chloride. Inherent viscosities of polyamides were in the range 0.64–0.72 dL/g indicating formation of medium molecular weight polymers. The weight average molecular weights and number average molecular weights, determined by gel permeation chromatography (polystyrene standard), were in the range 54,500–65,000 and 19,750–27,000, respectively. The constitutional isomerism of synthesized polyamides was investigated by 1 H and 13 C NMR spectroscopy, where as the constitutional order was calculated from 1 H NMR spectroscopy and was found to be in the range 0.35–0.37. Polyamides containing pendant groups were essentially amorphous and were soluble in polar aprotic solvents such as N , N -dimethyl acetamide, N -methyl-2-pyrrolidone, N , N -dimethyl formamide and dimethyl sulfoxide. Polyamides exhibited glass-transition temperature in the range 237–254 °C. The initial decomposition temperature, determined by TGA in nitrogen atmosphere, of polyamides was in the range 371–410 °C indicating their good thermal stability.

Novel dibenzylpiperidinium salts with nonnucleophilic anions (DBPi-SbF6, DBPi-PF6) have been prepared as latent cationic initiators. Utility of these salts in the photo and thermal-induced cationic polymerizations of epoxide and vinyl ether monomer systems has been studied. The new initiator, DBPi-SbF6 showed good solubility, high reactivity, and high thermal latency for polymerizations of epoxide and vinyl ether monomers with only 1 wt % of concentration. Cationic polymerization of vinyl ether monomer was significantly faster than epoxide monomer by the synthesized initiators. This article describes the synthesis, characterization, and activity of novel initiators. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Novel Sulfonium salts with non-nucleophilic anions were synthesized and applicability of these salts as initiators was demonstrated by carried out polymerization (photo and thermal) of epoxides as well as vinyl ether monomers. Newly synthesized initiators showed good activity for the photo and thermal polymerization. Synthesis, characterization, and activity of initiators have been described. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008.

A novel diimide-diacid (DIDA) monomer, 4-{4-[(4-methyl phenyl) sulphonyl]}-1,3-bis-trimellitoimido benzene containing sulphone and bulky pendant groups was successfully synthesized and used to synthesize a series of wholly aromatic poly(amide-imide)s (PAIs) by direct polycondensation method. The direct polycondensation of newly synthesized DIDA with different diamines was carried out via Yamazaki’s phosphorylation method using triphenyl phosphite and pyridine system. The resulting poly(amide-imide)s were obtained in quantitative yields with inherent viscosities 0.36–0.47 dl/g in DMAc at 30 ± 0.1 °C. The poly(amide-imide)s were amorphous and were readily soluble in various solvents such as N-methyl-2-pyrrolidinone (NMP), N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), dimethylsulfoxide (DMSO), and pyridine. Tough and flexible films were obtained by casting their DMAc solution. According to thermogravimetric analysis, the polymers were fairly stable up to temperature around 396 °C, and 10% weight losses in the temperature range of 476–511 °C that showed good thermal stabilities of these polymers.

A simple and convenient method for synthesis of ad- vanced isoindolone intermediates of lennoxamine and analogues is described in this paper. The intramolecular Diels-Alder reaction of furan is used as a key step in this synthesis.

Atom transfer radical polymerization (ATRP) was used to prepare poly(acetoxystyrene) (PAS) with a controlled molecular weight and narrow polydispersity. Using 1-phenylethylbromide (PEBr)/CuBr/Cu(0)/2,2′-bipyridine as an initiating system, the heterogeneous ATRP of 4-acetoxystyrene was carried out to form PAS as a precursor polymer. The reaction follows the first-order kinetics with respect to the conversion of monomer. A linear molecular weight (polydispersities Mw/Mn = 1.07–1.27) indicates the “living”/controlled nature of polymerization. The obtained PAS was chemically modified to obtain succinylated poly(hydroxystyrene) (Succ-PHS). The formulation of Succ-PHS, crosslinker (benzoguanamine-formaldehyde), and triphenylsulfonium triflate (TPST) as a photo acid generator (PAG) was carried out by UV irradiation using an i-line tool. The performance of the resultant polymer as the negative resist pattern photoresist for photolithography was studied with instrumental techniques. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3560–3566, 2007

Novel 1-methoxycarbonylethylmethylphenylsulfonium salts with nonnucleophilic anions, namely, hexafluorophosphate, hexafluoroantimonate, and tetrafluoroborate, were synthesized by the reaction of 1-methoxycarbonylethylphenylsulfide and dimethyl sulfate followed by anion exchange with potassium hexafluorophosphate, sodium hexafluoroantimonate, and sodium tetrafluoroborate, respectively. The cationic polymerization (photopolymerization and thermal polymerization) of epoxy and vinyl ether monomers was carried out to demonstrate the applicability of the newly synthesized sulfonium salts. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3157–3163, 2007

Two diamine monomers, 4-[4-(1-methyl-1-phenylethyl)phenoxy]-1,3-diamino benzene and 4-{4-[(4-methylphenyl)sulfonyl]phenoxy}-1,3-diamino benzene, were synthesized, and both diamines were polycondensed with three commercial dianhydrides to obtain aromatic polyimides containing pendant groups. The polyimides were characterized by solubility tests, viscosity measurements, IR, 1H-NMR, and 13C-NMR spectroscopy, X-ray diffraction studies, and thermogravimetric analysis. The polyimides had inherent viscosities of 0.33–0.58 dL/g in m-cresol at 30 ± 0.1°C. All the polyimides were amorphous and were soluble in solvents such as N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N,N-dimethylformamide, and m-cresol. Thermogravimetric analysis of the polyimides indicated no weight loss below 410°C under a nitrogen atmosphere. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1377–1384, 2005

A series of aromatic polyamides containing an s-triazine ring with thiophenoxy linkages was synthesized from two new diacids, namely 2,4-bis-(4-carboxyphenoxy)-6-thiophenoxy-s-triazine and 2,4-bis-(3-carboxyphenoxy)-6-thiophenoxy-s-triazine, and commercially available aromatic diamines by using Yamazaki's phosphorylation reaction. The polyamides were obtained in good yields and were characterized by solubility tests, viscosity measurements, FTIR, 1H and 13C NMR spectroscopy, X-ray diffraction studies and thermogravimetric analysis. The polyamides were found to have inherent viscosities in the range of 0.35 to 0.56 dl g−1 in N,N-dimethylacetamide (DMAc) at 30 ± 0.1 °C. All the polyamides were readily soluble in solvents such as DMAc, N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF) and m-cresol. Thermogravimetric analysis of the polyamides indicated no weight loss below 345 °C under a nitrogen atmosphere. Copyright © 2004 Society of Chemical Industry

1,3-Dicyclohexylcarbodiimide (DCC) has been exploited as an activating agent for nucleoside-H-phosphonates in the solution as well as solid phase synthesis of oligonucleotide and is effective in terms of speed and coupling efficiency.

The enantioselective Michael addition of dimethyl malonate to 1,3-diphenylprop-2-en-1-one promoted by a quaternary derived ammonium salt from quinine as a phase transfer catalyst in different ionic liquids, 1-butyl-3-methyl imidazolium hexafluorophosphate, [bmim]PF 6 , 1-butyl-3-methyl pyridinium tetrafluoroborate, [bpy]BF 4 , 1-butyl-3-methyl imidazolium tetrafluoroborate [bmim]BF 4 as well as in conventional organic solvents was studied.

The scope of nickel boride as a versatile reducing reagent is extended to the 3-oxidopyrylium-alkene [5 + 2] cycloadducts. In this report, we demonstrate that nickel boride is capable of one-pot 1,2- and 1,4-reduction of enones present in the cycloadducts in good yields. Subsequent elaboration of the cycloadducts towards synthesis of functionalized cycloheptenoid derivatives devoid of the oxa-bridge is also explored.