Synthesis and kinetic resolution of furyl substituted secondary carbinols by porcine pancreatic lipase under solvent free conditions

Chiral furyl substituted carbinols were prepared from the related carbonyl compounds and their enzymatic kinetic resolution was studied by using porcine pancreatic lipase (PPL) in transesterification reaction under solvent free condition. This study revealed that carbinols having one less bulky group on the chiral center are good substrates for PPL and the resolution proceeds with higher ee,s and less reaction time.     

Synthesis and Characterization of Novel Monoazo Naphthalimide Disperse Dyes Containing Carboxylic Acid Group with High Heat Fastness Properties

A group of novel monoazo disperse dyes containing carboxylic acid‐1,8‐naphthalimide group has been synthesized. All intermediates and dyes were purified by recrystalization and the column chromatography method. The purified products were characterized by ¹H NMR, ¹³C NMR, FTIR, DSC, UV‐VIS and Elemental Analysis. Spectrophotometric investigations of the synthesized dyes in different solvents were carried out in order to obtain their absorption maxima, molar extinction coefficients and solvatochromic effects. The absorption maxima of the synthesized dyes in acetone varied (513‐549 nm) and the molar extinction coefficient was (17405‐38939 l/mol cm). By changing the media from chloroform to DMF, the solvatochromism effect for all dyes increased. Dispersion of the synthesized dyes was prepared in water containing dispersing agent and applied to polyester fabrics. The dyed fabrics showed that all of the synthesized dyes were suitable for coloring polyester fibers, producing deep red to bluish red with very good fastness properties.     

Long-term and penalty contracts in a two-stage supply chain with stochastic demand

Recent applications of game-theoretic analysis to supply chain efficiency have focused on constructs between a buyer (the retailer or manufacturer) and a seller (the supplier) in successive stages of a supply chain. If demand for the final product is stochastic then the supplier has an incentive to keep its capacity relatively low to avoid creating unneeded capacity. The manufacturer, on the other hand, prefers the supplier’s capacity to be high to ensure that the final demand is satisfied. The manufacturer therefore constructs a contract to induce the supplier to increase its production capacity. Most research examines contracting when final demand is realized after the manufacturer places its order to the supplier. However, if final demand is realized before the manufacturer places its order to the supplier, these types of contracts can be ineffective. This paper examines two contracts under the latter timing scenario: long-term contracts in which the business relationship is repeated, and penalty contracts in which the supplier is penalized for too little capacity. Results indicate long-term contracts increase the profit potential of the supply chain. Furthermore, the penalty contracts can ensure that the supplier chooses a capacity level such that the full profit potential is achieved.     

Design,two-directional synthesis,DFT study of new pyrimido[5,4-d]pyrimidine-2,8-dione derivatives

A facile two-directional synthesis of new pyrimido[5,4-d]pyrimidine-2,8-dione was reported via an efficient reaction of premade bis-aldehydes and 1-(2-amino-1,2-dicyanovinyl)-3-phenylurea in the presence of triethylamine as the base and Cu (II) as catalyst. As there is controversy about the formation of two types of products, that is, purine or pyrimidine ring containing compounds in the reaction of diaminomaleonitrile with isocyanates and aldehydes, the computational model chemistry has been employed to obtain new insight about this reaction and determining the dominant pathway of the process. Using DFT model, two alternative pathways have been explored and geometrical isomerization of central double bond has been considered. Accordingly, the evaluated energy barriers affirm the formation of six-membered pyrimidine ring as the major product in the presence of CuCl₂ as the catalyst and MeOH as solvent.     

Synthesis and photochromic behavior of mono-, and biphotochromic system linked by p-phenylene bridge

<正>The synthesis of mono- and bis-l,3-diazabicyclo[3.1.0]hex-3-ene derivatives with indole ring and p-phenylene spacer,which behave as photochromic materials,is reported.The structure-photochromic behavior relationship(SPBR) of the synthesized compounds has been analyzed.     

Microwave-Assisted Synthesis of Coumarins via Pechmann Condensation in Wet Phosphoric Acid Imidazolium Dihydrogenphosphate

Phosphoric acid imidazolium dihydrogenphosphate was found to work well as a catalyst and excellent reaction medium in the Pechmann condensation of substituted phenols or α-naphthol with ethyl acetoacetate to give 4-methyl coumarins under microwave irradiation. This method is simple, cost effective, requires short reaction times, and gives very good to excellent yields.     

Measuring the Electrical Conductivity of Carbon Nanotubes Grown on Sodalime Glass Substrates using Cu as Catalyst

We have studied the electrical resistance of carbon nanotubes (CNTs) grown on sodalime glass using Cu as catalyst at 580°C temperature. The conductivity was measured at room temperature using four point probe technique. The Cu catalyst was coated on glass substrate by using dc magnetron sputtering system and etched by hydrogen (H₂) gas in order to form nanometer sized catalytic particles. Mixture of C₂H₂/H₂/Ar (20:80:100 standard centimeter cubic per minutes) gases were heated at 580°C for growth of CNTs on a glass substrate by using Thermal Chemical Vapor Deposition (TCVD). The temperature dependence of sheet resistance and current-voltage characteristics of the film were measured by a four point probes method. The morphology of the catalyst surface was probed by Atomic Force Microscopy (AFM), and the growth behavior of CNTs was investigated by scanning electron microscopy (SEM).     

Ultrasound-promoted regio and chemoselective synthesis of pyridazinones and phthalazinones catalyzed by ionic liquid [bmim]Br/AlCl3

The first ultrasound-promoted multicomponent synthesis of pyridazinones and phthalazinones from arenes, cyclic anhydrides and ArNHNH₂ in the presence of an efficient recyclable catalyst, [bmim]Br/AlCl₃, in high yield and short reaction time is reported.