Crystallization of N-cyclohexyl ammonium resorcinarene triflate from methanol results in a dimeric capsule capable of trapping two triflate anions and two methanol molecules within a 341 Å cavity while with 1,4-dioxane as a guest it forms a new larger dimeric capsule with volume of 679 Å encapsulating four 1,4-dioxane and four water molecules, resulting in packing coefficients of 0.75 and 0.67,...

The synthesis of the title compounds is described. Reaction of 1-substituted 2-pyrazolin-5-ones with 5-chloro-1-phenyl-1H-pyrazole-4-carbonyl chloride or 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-carbonyl chloride, respectively, using calcium hydroxide in refluxing 1,4-dioxane gave the corresponding 4-heteroaroylpyrazol-5-ols, which were cyclized into 1H-pyrano[2,3-c:6,5-c]dipyrazol-4(7H)-ones b...

Polytriarylamine copolymers can be prepared by Suzuki-Miyaura cross-coupling reactions of bis N-methyliminodiacetic acid (MIDA) boronate ester substituted arylamines with dibromo arenes. The roles of solvent composition, temperature, reaction time, and co-monomer structure were examined and (co)polymers prepared containing 9, 9-dioctylfluorene (F8), 4-sec-butyl or 4-octylphenyl diphenyl amine (...

Seventy-two hundred potential inhibitors of the histone deacetylase (HDAC) enzyme family, based on a 1,3-dioxane diversity structure, were synthesized on polystyrene macrobeads. The compounds were arrayed for biological assays in a "one bead-one stock solution" format. Metal-chelating functional groups were used to direct the 1,3-dioxanes to HDAC enzymes, which are zinc hydrolases. Representati...

The dissociation of 2% 1,4-dioxane dilute in krypton was studied in a shock tube, ST, using laser schlieren densitometry, LS, at 1550-2100 K and 123±2 Torr. Products were identified by ST/time-of-flight mass spectrometry. 1,4-dioxane was found to initially dissociate via C-O bond fission followed by a 2,6 H-atom transfer to the O atom at the scission site. Simulations of the LS profiles with a ...

The anticipated worldwide increase in biodiesel production will result in an accumulation of glycerol for which there are insufficient conventional uses. The surplus of this by-product has increased rapidly during the last decade, prompting a search for new glycerol applications. We describe here the synthesis of dissymmetric chlorohydrin esters from symmetric 1,3-dichloro-2-propyl esters obtai...

1,4-Dioxane has been identified as a probable human carcinogen and an emerging contaminant in drinking water. The United States Environmental Protection Agency's (U.S. EPA) National Exposure Research Laboratory (NERL) has developed a method for the analysis of 1,4-dioxane in drinking water at ng/L concentrations. The method consists of an activated carbon solid-phase extraction of 500-mL or 100...

A series of 3,5-disubstituted pyrazole-1-carboxamides were obtained by treatment of chalcones with semicarbazide hydrochloride in dioxane containing sodium acetate/acetic acid as a buffer solution. N-acetyl derivatives of pyrazole-1-carboxamides were isolated in good yields either by treatment of the carboxamide derivatives with acetic anhydride or refluxing chalcones with semicarbazide in etha...