bluuebunny/crossref_metadata_2025 huggingface dataset:
Cycloalkanes XI. Friedel‐Crafts Condensation of Polynuclear Aromatic Compounds with Cis‐4‐Cyclohexene‐1, 2‐Dicarboxylic Acid Anhydride
Authors: Mathur K. C. , Saxena M. K.
Published: June 2015

The anhydride of cis‐4‐cyclohexene‐1,2‐dicarboxylic acid was condensed with phenanthrene, acenaphthene and fluorene in the presence of anhydrous aluminium chloride to give the corresponding 2‐(aroyl) cyclohex‐4‐ene‐1‐carboxylic acids. These keto acids when subjected to Wolf‐Kishner reduction yielded the corresponding 2‐(aryl) cyclohex‐4‐ene‐1‐carboxylic acids, which were then converted into their respective acid chlorides by refluxing with thionyl chloride in benzene. The acid chlorides in turn were cyclised by anhydrous aluminium chloride in carbon disulphide to give the corresponding cyclic ketones. These cyclic ketones were then reduced by Wolf‐Kishner method to furnish the desired hydrocarbons, 2,3‐cyclohex‐2′‐ene‐5,6‐substituted cyclohexanes.
2‐Methyl‐1, 4‐Naphthoquinone Thiosemicarbazone as a Sensitive and Selective Chromogenic Reagent for Microdetermination of Palladium (II)
Authors: Kamini (Miss) , Singh S. K. , Sindhwani S. K. , Singh R. P.
Published: June 2015

A simple, sensitive and selective procedure has been developed for the spectrophotometric determination of palladium. Palladium (II) reacts with 2‐methyl‐1,4‐naphthoquinone thiosemicarbazone to form an orange brown complex in the pH range 8.2–9.5. The sensitivity, in terms of Sandell's definition, is 0.0025 μg Pd/cm2 at 500 nm. The system adheres to Beer's law upto 2.66 ppm of palladium and optimum concentration range for the determination of the metal is 0.3–2.29 ppm with molar absorbtivity of 4.2×104 ℓ mole−1 cm−1. The complex has 1:1 molar composition, as deduced by Job's method. The determination of palladium has been carried out in presence of foreign ions especially in presence of eighth group metals.
New Lignan Detetrahydroconidendrin from Juniperus Formosana Hayata
Authors: Kuo Yueh‐Hsiung , Wu Tseng‐Rong , Lin Yau‐Tan
Published: June 2015

Six crystalline compounds, isocedrolic acid, δ‐cadinol, emodin, sugiol, Δ5‐dehydrosugiol, and a new lignan phenol were isolated from the acetone extractive of wood of Juniperus formosana Hayata. The new lignan phenol was established as detetrahydro‐conidendrin by chemical and physical evidence.
Theoretical Infrared Radiative Lifetimes for CO a3∏
Authors: Lie G.C.
Published: June 2015

INDO self‐consistent‐field method was employed to calculate the potential energy and dipole moment functions for the excited a3∏ state of CO. Vibrationally averaged dipole moments and infrared radiative lifetimes were then obtained from the dipole moment function and vibrational wave functions generated by solving numerically the Schrödinger equation for nuclear motions. The calculated dipole moment is 1.468 (expt'I 1.375 D) for ν=0, and decreases with increasing ν, as found experimentally. Calculated infrared radiative lifetimes, with experimental results in parentheses, are 13.5 (17.3, 19.0±5.9), 7.3 (7.8, 13.1±2.9), and 5.0 (4.7, 5.6±1.0) msec, respectively, for ν=1, 2, and 3. The polarity of calculated dipole moment is C+O−, differing from that for the ground X1∑+ state. The origin of this difference is found to be due to the delocalization of the 5a orbital in the a3∏ state.
Stability Constants of Rare Earths with Violuric Acids
Authors: Singh B. P. , Bhardwaj V. K. , Singh B. R. , Ghosh R.
Published: June 2015

The metal ligand stability constants of violuric acid [H2VA], N‐methyl violuric acid [H2MVA], N‐phenyl violuric acid [H2PVA] and N‐(o‐m‐p) tolyl violuric acids [N‐H2(o‐m‐p)TVA] with La(III), Ce(III), Pr(III), Nd(III), Sm(III), Eu(III), Gd(III), Dy(III), and Ho(III) have been determined potentiometrically in 50 Vol% ethanol water media at 25°C and at an ionic strength of 0.1 M NaClO4. The stability of the complexes follow the order of basicities of ligands and also the electron affinities of rare earths as measured by their overall ionisation potential. The order of stabilities of rare earths with violuric acids is,

La3+ < Ce3+ < Pr3+ < Nd3+ < Sm3+ < Gd3+ < Eu3+ < Dy3+ < Ho3+.
Stereochemistry of the Reactions of Cyclic Ketones with Lithium Aluminum Hydride and Methyllithium. IV. The Stereochemistry of the Reactions in 2,2‐Dimethyl‐4‐t‐Butylcyclohexanone Systems
Authors: Rei Min‐Hon , Chen C. L. , Liu H. L.
Published: June 2015

Previous publication showed that the stereochemistry of lithium aluminum hydride reduction of cyclic ketones can be evaluated by the use of an empirical equation, . This paper reports further test of this relationship in the new system of 2,2‐dimethyl‐4‐t‐butyl‐cyclohexanone.

Lithium aluminum hydride reduction of this ketone yields 95.6% trans‐alcohol (lit., 95.9%) corresponding to D̊(D̊G*)H of 1.67 Kcal/mol. With methyllithium, the ketone formed 77.5% of trans‐alcohol (D̊(D̊G*)D̊fs = 0.67 Kcal/mol). These data give a calculated D̊G* = 0.74 Kcal/mol which agrees well with the literature value of 0.87 or 0.28 Kcal/mol.

Structural assignments of 2,2‐dimethyl‐4‐t‐butylyclohexanone, 1,2,2‐trimethyl‐cis‐ and trans‐4‐t‐butylcyclohexanols by pmr spectroscopic method are also given.
Electrode Kinetics of Lead in N‐(3‐Aminopropyl)‐Diethanolamine Solution at the Dropping Mercury Electrode
Authors: Chang L.C.
Published: June 2015

The lead complex of N‐(3‐Aminopropyl)‐Diethanolamine (APDEA) was investigated polarographically over the pH range 10.40‐12‐85 and ligand concentration 0.0227‐1.002M. A quasi‐reversible and diffusion‐controlled reduction wave was obtained at pH≥10.40. The electron‐transfer coefficient and rate constants were determined as 0.11‐0.34 and 10−4 cmsec−1, respectively.
Studies on the Extractive Constituents of the Nutmeg of Myristica Fragrans Houtt
Authors: Kuo Yueh‐Hsiung , Lin Yih‐Tsung , Lin Yau‐Tan
Published: June 2015

From the hexane extractive of the nutmeg of Myristica fragrans Houtt, glyceryl trimyristate (1), myristicin (11), methyleugenol (12), elemicin (13), dehydrodiisoeugenol (9), 1‐(3,4,5‐trimethoxyphenyl)‐2‐(4‐allyl‐2,6‐dimethoxyphenoxy)‐propan‐1‐ol (4), 1‐(3,4‐methylenedioxyphenyl)‐2‐(4‐allyl‐2,6‐dimethoxyphenoxy)‐propan‐1‐ol (6), and a new compound 1‐(3,4‐dimethoxyphenyl)‐2‐(4‐allyl‐2,6‐dimethoxyphenoxy) propan‐1‐ol (14) were isolated. The structure of compound (14) was determined to be an analogue of the β‐0‐4 ether type of dilignols.
Study of Sorption Properties of Amorphous Zirconium Phosphate
Authors: Lee Chi‐So , Chang Fu‐Chung , Yeh Yu‐Chai , Wu Shaw‐Chii
Published: June 2015

Amorphous zirconium phosphate ion‐exchanger has been prepared in our laboratory according to the procedure given by Gal and Gal. The Chemical composition has been determined. Some chemical properties; stabilities and sorption of mono‐ to hexavalent cations have been studied in detail. It was found that washing the zirconium phosphate ion exchanger with alcohol before drying would increase the exchange capacity of amorphous zirconium phosphate.
Quantitative Analysis of Clove Oil by NMR Spectrometry
Authors: Chiang Hung‐Cheh , Wang Pei‐Lein , Huang Keh‐Feng
Published: June 2015

A procedure utilizing NMR spectrometry in the quantitative analysis of clove oil is described. The 1H‐NMR spectrum is determined with acetophenone as internal standard, the 13C‐NMR spectrum is determined with chloroform as internal standard and 0.1M Cr(acac)3 as relaxation reagent. The contents of eugenol are compared to the results obtained from G.C. (90.8%, s.d. 0.7%) and from chemical method (89.6% s.d. 1.2%).

The result obtained from 1H‐NMR method is 90.4% (s.d. 0.3%) and from 13C‐NMR method is 90.5% (s.d. 0.7%). The time required for the 1H‐NMR method is about 20mins and for the 13C‐NMR method is about 2‐3hours. Apparently the 1H‐NMR method proves to be more simple, rapid and accurate.
Chemical Reactions of Coumarins and Furocoumarins on Thin‐Layer Chromatoplates
Authors: El‐Tawil B. A. H. , El‐Beth F. K. A.
Published: June 2015

Most of the reaction achieved in this work were conducted with coumarin and furocoumarin. The reactions were performed on inert thin‐layer chromatoplates under controlled conditions and the products of the reactions were compared as usual with the expected substances on the same chromatogram. The reactions performed were: mineral acid hydrolysis, methylation, acetylation, benzoylation, nitration and Schiff's bases on silica gel chromatoplates.
On the Reduction of Copper Oxide
Authors: Wang Hong‐Paul , Yeh Chuin‐Tih
Published: June 2015

The reduction of CuO with hydrogen has been studied with a temperature programmed reduction technique. According to a proposed reduction mechanism, the reduction was initiated with a interaction between hydrogen and active sites of copper oxide, the rate of the reduction was limited by the diffusion of water from the crystalline. The activation energy of this diffusion is found to be 13Kcal/mol. Reoxidation of copper powder may cause redispersion of the crystalline. The chemical interaction between copper oxide and Cabosil is found very weak.
Determination of Metal Ions by High Performance Liquid Chromatography
Authors: Hwang Jon‐Mau , Chang Fu‐Chung , Yeh Yu‐Chai
Published: June 2015

The mixture of metal ions [Bi(III), Fe(III), Fe(II), Cu(II), Zn(II), Ni(II), Co(II), Pb(II), Cd(II), Mn(II)] were separated in the bonded‐phase strong cation exchange column (Vydac‐401 SA) and monitored at 540 nm after a postcolumn reaction with 4‐(2‐pyridylazo)‐resorcinol (PAR). Citrate, tartrate, lactate and α‐hydroxyisobutyrate buffer were used as eluent and it has been found that the elution order of some metal ions were changed with different eluents. The detection limits and the calibration curves of metal ions were also studied.
Thermodynamic Studies on the Complexation Reactions of Copper(II) Complex of o2n2‐Donor Macrocycle with Halide and Pseudohalide Ions
Authors: Wang Bind , Lin Yi‐Jen , Chung Chung‐Sun
Published: June 2015

Complexation reactions of 5,6,7,8,9,10,16,17‐octahydrodibenzo[e, m][1, 4]dioxa‐[8, 11]diazacyclotetradecine‐copper(II) complex with halide and pseudohalide ions have been studied at 25.0° in three water‐methanol mixed solvents by spectro‐photometric method. It is found that the equilibrium constants increases in the order of 50 vol.% CH3OH<75 vol.% CH3OH<95 vol.% CH3OH for solvents and I‐<Br−<CI−<SCN−, N−3 for anions.
The Observation of Metastable Transitions in a High Resolution Double Focussing Mass Spectrometer
Authors: Lin D. P.
Published: June 2015

Three metastable transitions are observed with 31 5‐t‐butyldimethylsiloxy‐dehydrosterone (BDMS‐DHEA) by detecting their daughter ion at m/z 269 in a double focussing mass spectrometer. Because of their specificity, the transitions of molecular ion could be served as quantitation routes for the determination of the steroid in human blood plasma using direct insertion probe with ionization chamber temperature ≥230°C. Thus, as is in MS/MS it would significantly reduce sample work‐up time and possibly eliminate the need for a GC separation in detecting the level of this steroid in human blood.
Determination of Ga, Th, and U in Bauxite and Coal Ash by Epithermal Neutron Activation Analysis
Authors: Wu H. C. , Chen S. G. , Tsai H. T.
Published: June 2015

Neutron activation analysis is applied to the determination of Ga, Th and U in Bauxite and coal ash; thermal and epithermal irradiations are used. The other analytical methods are also quantitatively surveyed for gallium. The results indicate that epithermal neutron activation is prefered for those trace elements because the former method is more simple and quick.
Using NAA to the Determination of Antimony in Trichlorosilane with Substoichiometric Extraction
Authors: Chen S. G. , Tsai H. T.
Published: June 2015

Neutron activation analysis has been applied to the determination of trace of antimony based on the substoichiometric extraction of Sb(III) with BPHA (N‐benzoyl‐N‐phenyl hydroxylamine). The antimony contens in trichlorosilane or high purity silicon can be determined by the proposed method down to ppb range. The effect of acid concentration, shaking time, the amount of carrier and the decontamination factors were studied.
Spectrophotometric Determination of Dioxovanadium (V) Ion Using Some Halogen Derivatives of Phenylazo‐Chromotropic Acid
Authors: Badawy S. S. , Issa Y. M.
Published: June 2015

A comparative study of the reaction of o‐chloro‐, m‐chloro‐, p‐chloro‐, p‐bromo‐ and p‐iodophenylazo‐chromotropic acids with dioxovanadium (V) ion have shown that 1:1 and 1:2 violet water soluble complexes were formed at pH 4.5. The p‐halogeno‐derivatives were found to be very suitable reagents for spectrophotometric determination of VO+2 up to 8 ppm. The application of these dyes as indicators in the spectrophotometric titration of VO+2 with EDTA and the interference of a various cations and anions were reported.
Synthesis of Cardioactive Steroids III Modified Synthetic Route to Isocardenolide
Authors: Shiao Min‐Jen
Published: June 2015

A modified synthetic route to isocardenolide (I) via furan intermediate (6) was studied. The diene (4) could easily be synthesized from carbinol (1) or acetate (2). Dissolving metal reduction of diene (4) to Δ1, 17β‐furyl compound (6) was successfully achieved.
Solvent Extraction Studies of Two Isomeric 5, 7, 7, 12, 12, 14‐Hexamethy‐1, 4, 8, 11‐Tetraazacyclotetradecanes
Authors: Liu Landie , Wu Jung‐Chung , Chung Chung‐Sun
Published: June 2015

The distribution ratios of two isomeric 5, 7, 7, 12, 12, 14‐hexamethyl‐1, 4, 8, 11‐tetraazacyclotetradecane, tet c and tet d, in several solvent systems at 25.0°C as functions of hydrogen ion concentration were determined. The protonation constants and the distribution constants of these macrocyclic ligands and their protonated species were obtained from the variations of the distribution ratios in the range of 6<–log [H+]<14.
A Spectroscopic Study of the Hemiammine Dicobalt (II) Species
Authors: Chu Vincent H. K.
Published: June 2015

Infrared spectrum of amyl amine forming cobalt complex in benzene solution is described. The D, value and transitions between d orbitals are identified. Since few transition metal salts are soluble in inert solvent, this paper introduces a special method of making cobalt‐2‐ethyl‐hexanoate which is soluble in benzene.
Diels‐Alder Reactions of 6,9‐Dipropyl‐1, 4‐Dioxaspiro[4.5]Deca‐6, 8‐Diene‐2, 10‐Dione with Substituted Alkenes. An Entry to Bicyclo[2.2.2]Oct‐5‐Ene‐2, 3‐Diones and 1, 3‐Cyclohexadienes
Authors: Hsu Y. H. , Kuo L. C. , Liao C. C. , Lin H. S. , Uang B. J.
Published: June 2015

The cycloadditions of the title compound, 1, a masked 3, 6‐dipropyl‐o‐benzoquinone to various disubstituted (diethyl maleate, diethyl fumarate, trans‐ and cis‐stilbene, and cycloheptene) and monosubstituted alkenes (methyl acrylate, methyl vinyl ketone, styrene, ethyl vinyl ether, and 1‐hexene) have been studied; the yields of the Diels‐Alder adducts, 2, are generally high (> 75%) except for stilbenes. These adducts are effectively transformed into the corresponding bicyclo[2.2.2]oct‐5‐ene‐2, 3‐diones, 3, whose stereochemistries are determined from the ring current effect of the respective quinoxalines, 4, on the chemical shifts of the vinyl and the methine protons and/or the lanthanide (Eu(fod)3) induced shift on the pertinent protons of 3. It is interesting to note that the quinoxaline ring current makes the vinyl protons down‐field shifted by 0.15–0.27 ppm whereas the methine protons (R3=H) syn to the quinoxaline moiety up‐field shifted by 0.18–0.39 ppm as compared to the chemical shifts of the corresponding protons in 3. The transformations of α‐diketones 3 into the corresponding 1, 3‐cyclohexadienes, 5, by irradition with a Hanovia medium pressure lamp through a uranium glass filter are almost quantitative. The present study provides facile and effective methods for the preparation of bicyclo[2.2.2]oct‐5‐ene‐2, 3‐diones and 1, 3‐cyclohexadienes from catechols via masked o‐benzoquinones.
Composition of Peel Essential Oils from Eight Citrus Species
Authors: Cheng Yu‐Shia , Chou Chun‐Tzer
Published: June 2015

The peel essential oils from eight citrus species growing in Taiwan were analysed to determine the detailed composition of each oil.
Computation of the Number of Isomers of Coordination Compounds Containing Identical Monodentate Ligands and Chelating Ligands
Authors: Chang Chi‐Chang , Chung Chung‐Sun
Published: June 2015

This paper outlines a simple method of counting the number of isomers of coordination compounds containing identical monodentate ligands and chelating ligands.
Molecular Structure of trans‐4‐p‐Tolylcyclophosphamide
Authors: Liu Ling‐Kang
Published: June 2015

The ‘trans’ assignment to the slower eluting diastereomer of 4‐p‐tolylcyclophosphamide is confirmed with a direct structure determination by X‐ray crystallography. The compound crystallizes in the monoclinic space group P2,/c with Z=4 and cell dimensions a=11.636(4), b=12.394(5), c= 11.819(5)Å, β=93.9(3)°. Final R and R are 0.063 and 0.063, respectively.
Determination of Trace Molybdenum in Biological Matrices by Neutron Activation Analysis
Authors: Lo Jem Mau , Yeh Si Jung
Published: June 2015

Based on consecutive extractions using bismuth diethyldithiocarbamate and thallium diethyldithiocarbamate as reagents, molybdenum was selectively and highly enriched from biological matrices, and then subjected to neutron activation analysis. Most of interfering elements, e.g., Na, K, Br, P, Fe, U, etc. were simultaneouly removed and the preconcentrated samples always showed only the r rays from molybdenum after neutron bombardment. Thus, molybdenum in the biological matrices could be accurately determined.
Chemistry of Leave Extractives from Cineole Tree
Authors: Kuo Yueh‐Hsiung , Chen Wen‐Chau , Lin Yau‐Tang
Published: June 2015

From the acetone extractive of the leaves of Cinnamomum camphora Sieb (cineole tree), β‐sitosterol, sesamin, dotriaconyl alcohol, piperitol, xanthoxylol, cinnamonol, β‐sitosteroyl‐l‐β‐glycopyranoside, and a new compound dotriaconyl‐trans‐coumarate were isolated.
A Stereospecific Synthesis of Cis‐3‐Substituted‐2, 2‐Dimethylcyclopropane‐L‐Carboxylates
Authors: Huang Chun‐Hsien , Chen Jih‐Sang
Published: June 2015

A stereospecific synthesis of cis‐3‐substituted‐2, 2‐dimethylcyclopropane‐1‐carboxylates based on the cyclization of 5‐bromolactone 2 to give bicyclic lactone 3 is described.
Synthesis of Ethyl Methyl Ether Over Solid Acid Catalysts
Authors: Ebeid Fikry M. , Ali Laila I.
Published: June 2015

The alkylation of methanol by triethylamine to form ethyl methyl ether was studied in the temperature range 310‐330°C using γ‐alumina and silica‐aluminas differing in their silica content. The effect of treating γ‐alumina with hydrochloric and boric acid on the reaction rate was also investigated. The results obtained for ether formation over γ‐alumina show that the reaction is first order for methanol and zero orde for triethylamine. Alumina‐H3BO3 was found to be the most active catalyst whereas alumina‐HCl is the least active towards ether formation. The activity of silica‐alumina is proportional to its silica contents.
An Automated Reagent‐Addition System with an Infrared Drop Detector
Authors: Marqubz Daniel V. , Aguilar Raul , Chang C. Allen
Published: June 2015

The design and implementation of a computer‐controlled automated reagent‐addition system is presented. A special feature is the use of an infrared drop detector to sense that a drop of the titrant has indeed been added to the titrate. This system is particularly useful for the determination of stability constants of metal complexes. The operational procedure is briefly discussed and examples are given to show that reproducible results are obtained.
Chemistry of o‐Benzoquinones and Masked o Benzoquinones VII.: Regioselective and Stereoselective Cycloadditions of 6, 7‐Dipropyl‐ and 8, 9‐Eipropyl‐1, 4‐Dioxaspiro[4.5] deca‐6, 8‐Di‐En‐2, 10‐Dione with Monosubstituted Ethylenes
Authors: Kuo Li‐Ching , Liao Chun‐Chen
Published: June 2015

The cycloadditions of the titled two masked o‐benzoquinones, 2 and 3, with monosubstituted ethylenes including ethyl acrylate, styrene, ethyl vinyl ether and 1‐hexene were studied. The reactions proceeded with high stereoselectivity and regioselectivity to give endo head‐to‐head adducts when ethyl acrylate, styrene and ethyl vinyl ether were used as addenda. In the case of 1‐hexene, the reaction with 2 took place with high regioselectivity but low stereoselectivity to afford endo as well as exo head‐to‐head adducts while the reaction with 3 occurred with less regioselectivity to produce presumably all the eight possible isomers. The regiochemistry of the adducts were determined by the 1H nmr analysis of their hydrolysis products, bicyclo[2,2,2]oct‐5‐en‐2,3‐diones 6, and the subsequent photolysis products, 1,3‐cyclohexadienes 7. The stereochemistry was established by the study of the lanthanide induced shifts of compounds 6a‐6f with Fu(fod)3. The regioselectivity and stereoselectivity of these cycloaddition reactions were explained in terms of frontier molecular orbital theory and steric effect. The present study provides also a facile method to prepare regioselectively bicyclo[2, 2, 2]oct‐5‐en‐2,3‐diones (stereo‐selectively also) and 1,3‐cyclohexadienes from unsymmetric catechols via masked o‐benzoquinones.
1,3‐Dipolar Cycloaddition of 5‐Substituted‐1‐Methyl‐3‐Oxidopyridiniums
Authors: Chen Ling‐Ching , Wang Eng‐Chi , Lin Jen‐Hom
Published: June 2015

5‐Methoxy‐ and 5‐dimethylamino‐1‐methyl‐3‐oxidopyridiniums were shown to give the 1,3‐dipolar cycloadducts widely with methyl acrylate, acrylonitrile, N‐phenylmaleimide, styrene, phenylacetylene, cyclopentadiene, cyclopentene, diethyl azodicarboxylate and singlet oxygen.
Mössbauer Spectroscopic Studies of Supported α‐Fe2O3 and Fe Catalysts I: Particle Size Determination and Support Effect
Authors: Wei Ho‐Hsiang , Lin Kuen‐Hai
Published: June 2015

The chemical state of particles of 5wt% Fe in α‐Fe2O3 and the subsequently reduced iron particles supported on different particle size (50–200 mesh) of silica (SiO2), alumina (Al2O3), magnesium oxide (MgO) and carbon (C) was examined by Mössbauer spectroscopy at various stages of calcination and reduction. The particle size of the α‐Fe2O3 supported on different mesh sizes (50, 100, 140, 200 mesh) of SiO2 has been determined. The strength of metal‐support interaction with respect to the kind of support was found to be MgO>SiO2>Al2O3>C.
Dissociation Constants of P‐Nitroanilinium Ion in Tetrahydrofuran‐Water Mixtures at 25°C by Spectrophotometric Measurements
Authors: El‐Harakany A. A. , Ramadan M. Sh.
Published: June 2015

A spectrophotometric method has been used for the determination of the dissociation constant of P‐nitroaniline indicator (which has a charge type A+B0) in various THF‐water solvent mixtures at 25°C. The dissociation constant is found to decrease with the addition of THF which indicates that the basicity of the medium is increased by the addition of the organic solvent.

The relative basicity of the medium is compared with other aqueous‐organic solvent mixtures and the trend of decreasing basicity is in the order THF‐H2O> DMF‐H2O > AN‐H2O > HAC‐H2O.
The Mechanism of Schiff Base Formation of Some Arylidenes‐p‐Aminosalicylic Acid
Authors: Adam F. A. , El‐Haty M. T. , Ibrahem A. A.
Published: June 2015

Formation of a series of Schiff bases derived from p‐aminosalicylic acid I and various aromatic aldehydes has been studied kinetically in ethanol medium in presence of piperidine as a basic catalyst. The order of the reaction is determined to each reactant by following the concentration of the Schiff base formed during the reaction. The reaction is Kinetically third‐order in the presence of low concentration of piperidine, first‐order to each of I, aldehyde and piperidine. On the other hand, in presence of ≥5×10−4 M of piperidine the order of the reaction changed to second‐order, thus much the reaction is independent of piperidine concentration. The rate determining step is suggested to be the dehydration of the carbinolamine intermediate step 4. Variation in reaction rate constants with the different substituent of the aromatic aldehyde, with substituents of aromatic amine and with the nature of the hydroxylic organic solvents as reaction medium are studied and discussed.
Syntheses and Mass Spectral Studies of (E)‐1‐Alkanesulfonylpropenes and (E)‐1‐Alkanesulfinylpropenes
Authors: Liu Lilian‐Kao , Hwang Wen Shwong
Published: June 2015

(E)‐1‐Alkanesulfonylpropenes and (E)‐1‐Alkanesulfinylpropenes have been synthesized in good to excellent yields. Studies correlating molecular structure and fragmentation patterns upon electron impact have been carried out. Double hydrogen rearrangements with the elimination of alkenyl radicals are the most facile fragmentations for (E)‐1‐alkanesulfonylpropenes. Single hydrogen rearrangement with alkene elemination is however the most important fragmentation for (E)‐1‐alkanesulfinylpropenes. In this case the hydrogen atom only migrates to the sulfinyl oxygen. These differences in fragmentation patterns between the (E)‐styryl‐alkyl‐sulfones/sulfoxides and the (E)‐propenyl‐alkyl‐sulfones/sulfoxides are attributed to the fact that different ionization sites are involved.
Syntheses of 1‐Azaazulan‐2‐One Analogs of Adrenergic Agents
Authors: Wu Chi‐Phi , Jiang George J. , Hung Ya‐Yung , Yang Paw‐Wang
Published: June 2015

The Friedel‐Crafts reaction of 1‐azaazulan‐2‐ones with α‐haloacid chloride in the presence of aluminum trichloride gives the corresponding α‐haloacyl derivatives. Treatment of these reaction products first with various secondary amines and then with sodium borohydride gives new adrenergic active amine derivatives.
Interfacing the Biomation 6500 Transient Digitizer to an Apple II Microcomputer
Authors: Su S. G. , Tsai C. H. , Su T. ‐M. , Mou C. Y.
Published: June 2015

An interface is described which permits high‐speed data transfer between the Biomation 6500 waveform digitizer and an Apple II microcomputer system. Through the interface, one can make any number of scans of repetitive data which, having been acquired by the Biomation 6500, may then be averaged, stored and analyzed in a microcomputer environment.
Spectrophotometry Determination of Cobalt after Extraction of its Ternary Complex with 3‐(4‐Phenyl‐2‐Pyridyl)‐5,6‐Diphenyl‐1,2,4‐Triazine and Tetraphenylborate into Molten Naphthalene
Authors: Lin Jenn‐Lin
Published: June 2015

The reaction of 3‐(4‐phenyl‐2‐pyridyl)‐5,6‐diphenyl‐1,2,4‐triazine (PPDT) and tetraphenylborate (TPB) with cobalt (II) has been studied to determine the optimum conditions for the extraction and quantitative spectrophotometry determination of this metal. The ternary complex is extracted into molten naphthalene at pH 3.6–7.4. The solid naphthalene containing the cobalt associated complex is separated by filtration and dissolved in acetonitrile. Beer's law is obeyed in the concentration range 8–140 μg cobalt in 10 ml of acetonitrile solution. The molar absorptivity and sensitivity are 4.2×103 l·mol−1·cm−1 and 0.01408 μg/cm2, respectively. The other factors such as pH, amounts of reagents and naphthalene, shaking and standing times, and the effect of diverse ions are studied. The method has been applied to the determination of cobalt in iron steel alloys.
Quantitative Determination of Iron Carbonyls on Polymer Supports
Authors: Chou Ta‐Shue , Yuan Yeh‐Jing , Feng Jung‐Jung
Published: June 2015

With the aid of FTIR analysis, the absolute amount of iron carbonyl complexes attached to a DVB/styrene copolymer backbone and the ratio of the biscoordination product to the monocoordination product were determined. These determinations were based upon the relative IR peak absorption areas at 2040 cm−1, 1880 cm−1, and 2915 cm−1 for the C=O stretching of monocoordination product, biscoordination product, and the C—H stretching of polymer backbone, respectively.
Regioselective Acylation of Cyclic α‐Silylallyl Sulphide
Authors: Chen Ling‐Ching , Chen Lih‐Ming , Lin Lih‐Hom
Published: June 2015

Acylation of cyclic α‐trimethylsilylallyl sulphide (3) by reaction with the acid halide catalyzed by aluminum chloride in CH2Cl3 at −78°C gave compound 4 in good yield with extremely high regio‐selectivity.
Synthesis of 5‐(3‐Tert‐Butylamino‐2‐Hydroxy) Propoxy‐3,4‐Dihydrocarbostyril
Authors: Chen Ling‐Ching , Lin Jen‐Hom , Wu Shihn‐Sheng
Published: June 2015

5‐(3‐tert‐Butylamino‐2‐hydroxy) propoxy‐3, 4‐dihydrocarbostyril (1, carteolol) was prepared by an acid‐catalyzed cyclization of the N‐pivaloylamino‐ester (5), which was obtained by using organolithiation of m‐pivaloylanisidine, followed by Wittig and catalytic hydrogenation reactions. The total yield of 1 obtained from m‐anisidine (2) is 21%.
Reactions of Aroylhydrazones, IV: Synthesis of Nitrogen Heterocycles from Opianic Acid Hydrazones
Authors: Nassr Mahmoud A.M. , El‐Badry Sousan M. , Smaban Mohammed A.E.
Published: June 2015

Opianic acid reacts with various hydrazines to yield either hydrazone (3, 6) or phthalazinone (4) derivatives depending upon the electronic properties of the substituent attached to the hydrazine molecule. Oxidative cyclization of opianic acid aroylhydrazones with iodine and yellow mercuric oxide gave the 1,3,4‐oxadiazole derivatives 21. The aroylhydrazones were also condensatively cyclized by heating with acetic anhydride to give the 1,3,4‐oxadiazoline derivatives 24. Structures assigned to the prepared compounds were corroborated by studying their chemical as well as their spectral characteristics.
Structure of 5‐Amino‐4‐Arylazopyrazoles in Ethanolic Aqueous Media
Authors: Fahmy H. M. , Elnagdi M. H. , Mahgoub A. Elsaid , Kasem A. , Ghali E. A.
Published: June 2015

The structure and tautomerism of 5‐amino‐4‐arylazopyrazoles (2a‐f) are investigated in aqueous media. In solutions of pH>5 these compounds exist as ring N—1 protonated species. At pH>10 they afford anions which are stabilized by delocalization of the negative charge in the ring as well as on the arylazo moiety. Controlled potential electrolysis and polarographic analysis indicate that 2a‐f are reduced via a four electron reduction process to triaminopyrazole and the corresponding substituted aniline derivative. A mechanism is suggested and discussed.
Reduction of Cd(II) and Mn(II) at the Dropping Mercury Electrode in the Presence of 1,3,5‐Trihydroxybenzene in Aqueous Sodium Perchlorate
Authors: El‐Maraghy Salah B. , Gutmann V. , Linert W.
Published: June 2015

Reduction of Cd2+ at the dropping mercury electrode in solutions of 1, 3, 5‐trihydroxybenzene was carried out in nonbuffer solutions of 0.1 M NaClO4. The polarogram consists of two waves, the first wave can be taken in quantitative determination of Cd2+ in solutions containing 3.5 mM 1, 3, 5‐trihydroxybenzene in 0.1 M NaClO4. Mn2+ produces single well‐defined diffusion controlled irreversible wave whose half‐wave potential shifts to a more negative value with increasing 1, 3, 5‐trihydroxybenzene. Me(II) forms two weak complexes, MX1 and MX2 at 25°. The behaviour of this metal ions is summarized.
Carbon‐13 NMR Studies of Some Sydnone Derivatives
Authors: Ma Sun , Yeh Mou‐Yung
Published: June 2015

The natural abundance carbon‐13 nuclear magnetic resonance spectra of 3‐arylsydnone, 3‐aryl‐4‐formylsydnone, 4‐acetyl‐3‐arylsydnone, 3‐aryl‐4‐cyanosydnone as well as some derivatives of the above compounds have been studied. The data indicate that the electron withdrawing effect on the C4 atom of the sydnone ring decreases in the sequence: C≡N>COCH3∼CHO. The solvent effect on the chemical shift has also been investigated.
Dye‐Sensitized Photooxidation of Isoeugenol
Authors: Chen Lien‐Huei , Kuo Yueh‐Hsiung
Published: June 2015

Sensitized photooxidation of isoeugenol gave 6 products. The elucidation of the structures of those products and the mechanism of their formation are discussed.
Reaction Dynamics of Electronically Excited Alkali Atoms with Simple Molecules
Authors: Weiss Paul S. , Mestdagh Jean‐Michel , Schmidt Hartmut , Vernon Matthew F. , Covinsky Michael H. , Balko Barbara A. , Lee Yuan T.
Published: June 2015

The reactions of electronically excited sodium atoms with simple molecules have been studied in crossed molecular beams experiments. Electronically excited Na(32P3/2,42D5/2, and 52S1/2) were produced by optical pumping using single frequency dye lasers. The effects of the symmetry, and the orientation and alignment of the excited orbital on the chemical reactivity, and detailed information on the reaction dynamics were derived from measurements of the product angular and velocity distributions.
Theory of Multi‐Photon Ionization of Atoms and Molecules
Authors: Fain B. , Kono H. , Lin S. H. , Henke W. E. , Selzle H. L. , Schlag E. W.
Published: June 2015

In this paper we present a density matrix formalism to treat one‐photon ionization and multiphoton ionization of atoms and molecules in the presence of an external field. It is shown that Fano's results for one‐photon ionization without an external field can easily be obtained from our formulation. For comparison, the Green's function method applied to multiphoton ionization of molecules is also presented.
Rotational Isomerism in O‐Methylphenol: Matrix‐Isolation Infrared Study and MNDO Calculations
Authors: Lin Ching‐Erh , Hsieh Ying Kang , Wu Yi‐Shuen , Tai T. L. , Chang S. L.
Published: June 2015

Rotational isomerism in o‐methylphenol was studied by matrix‐isolation infrared spectroscopy and MNDO calculations. Monomer molecules were isolated both in the argon matrix and in the nitrogen matrix near 10°K. The resolution of one weak band from the main hydroxyl absorption in the stretching and torsional regions evidently indicates the existence of two stable rotational isomers. Results of MNDO semi‐empirical molecular orbital calculations with full geometry optimization indicate that only two stable conformations can exist with the trans (stag) conformation being more stable than the cis (stag) conformation by 3.32 KJ/mole. The present experimental data are interpreted with the aid of theoretical MNDO calculations. The agreement between experiment and theoretical calculations is excellent. However, it was found that the CNDO/2 calculations would give misleading predictions on the relative stabilities of rotational isomers in the present case.
Intermolecular Nuclear Relaxations and Molecular Site‐Site Pair Correlation Functions in Liquids
Authors: Ju Chang‐Yuan , Hwang Lian‐Pin
Published: June 2015

Intermolecular nuclear relaxation studies of real liquids and the results of theoretical calculations for model potential functions have provided significant information on the role of molecular interactions in the structure of liquids. The intermolecular proton‐proton paircorrelation function (pcf), obtained from the reference interaction site model (RISM) is used as the equilibrium distribution and is used to obtarn an effective force for the calculation of intermolecular proton relaxation rates in liquid benzene, 1,3,5‐trideuterobenzene and ethane. For liquid ethane, better agreement with experiment is observed with the pcf obtained from the Monte Carlo simulation than with the RISM result.
Metal Oxide Film Anodes in the Electrolysis of Water or Brine
Authors: Hsu Shin‐Chu , Hseu Tong‐Ming , Lin Zui‐Feng
Published: June 2015

Metal (M) oxide (M: Ir, Os, Pd, Pt, Rh, Ru) together with MaO2 and MnO2 alone, were coated on SnO2 films and the anode behavior was examined in 1.0 N H2SO4, 1.0 N NaOH and 1.0, N NaCl aqueous solutions at 25°. The results are compared with those of DSA and of metallic Pt.
Crystal and Molecular Structure of Carbonyl (1,1,4,4‐Tetrafluoro‐2‐tert‐Butyl‐1,4‐Disilabut‐2‐Ene) (η5‐Cyclopentadienyl) Cobalt (II)
Authors: Lin W.P. , Liu C.S. , Wang Y. , Lee G.H.
Published: June 2015

(C3H5)Co(CO)(Si2F4C4H10) was synthesized by the photochemical reaction between dicarbonyl (η5‐cyclopentadienyl) cobalt and 1,1,2,2‐tetrafluoro‐1,2,‐disilacyclobutene. Its structure was identified by IR, NMR and mass spectrometry. The single crystal structure was studied for confirmation. The compound crystalized in a monoclinic space group P21/n with unit cell a=7.120 (6), b=20.334. (3), c=10.682(1) Å, β=90.97(8)°, Z=4 final R=0.050 for 3667 observed reflections. The molecule has a mirror plane symmetry about the Co atom coordination sphere. The reaction between the cobalt carbonyl and the 1,2‐disilacyclobutene produces only silicon‐cobalt σ bonds.
Comparative Study of Nickel Catalysts Supported on X‐ and Y‐Zeolites
Authors: Chien Shu‐Hua , Lu Kuang‐Lieh , Huang Hsiau‐Wen
Published: June 2015

We have made a comparative study of CO/H2 reactions over the nickel catalysts supported on X‐ and Y‐zeolites, prepared by incipient‐wetness impregnation (W) and ion‐exchange (E) methods. The catalysts were characterized by surface area and volumetric chemisorption measurements, temperature programmed reduction profiles, and x‐ray diffraction analysis. The results show that the turnover frequency decreases in the order; NiX(W)>NiY(W)>NiY(E)>NiX(E). The metal dispersion and catalytic activity of the catalyst are mainly affected by the support materials, the preparation methods, and the activation procedures. The high activity of NiX(W) was due to its higher reducibility, smaller nickel crystalline size, and better nickel dispersion. The low activity of NiX(E) was attributed to the poor ion‐exchange of Ni with NaX, the poor reducibility, the large crystalline size, and the poor nickel dispersion.
Nickel Boride Catalysts in Organic Synthesis (IV). The Effect of Water Washing on P‐2 Nickel Boride Catalyst
Authors: Sheu L. L. , Chen Y. Z. , Rei M. H.
Published: June 2015

Water washing of P‐2 nickel boride brings about a new catalyst designated as P‐2W nickel boride. This P‐2W catalyst is more reactive than P‐1 or P‐2 in the hydrogenation of cyclohexanone and nitrobenzene. The P‐2W, however, is less selective than P‐2 in the hydrogenation of cyclic olefins.
Synthetic Applications of the Direct Alkylation Reactions of 3‐Sulfolenes
Authors: Tso Hsi‐Hwa , Chang Lee‐Jean , Lin Lung Ching , Chou Ta‐Shue
Published: June 2015

The readily available sulfolenes can be used as the 1‐carbanion equivalent of the unsubstituted and substituted buta‐1,3‐dienes which can be directly alkylated. This convenient synthetic method is not only regiospecific, efficient and straight forward, but also favorable because the normally unstable molecules containing conjugated dienyl moiety can be prepared directly in their protected forms. The deprotection step is both clean and highly stereoselective. The applications of this type of reaction in organic synthesis include the trans‐β‐ocimene, α‐farnesene and a series of hydroindans and hydronaphthalenes.
Synthesis and Properties of Trimethylphenoxy‐ and Tetramethylphenoxy‐Silanes
Authors: Yang Mei‐Hui , Liang Jung‐Chang , Chao Ito , Liu Sheng‐Lieh
Published: June 2015

Twelve new Trimethylphenoxy‐ and Tetramethylphenoxy‐silanes were synthesized and all were proved to be stable toward hydrolysis. The substituent effect of methyl groups on the stability of Si‐O‐Ar toward hydrolysis is also discussed.
A New Lignan, Formosanol, from Juniperus Formosana
Authors: Kuo Yueh‐Hsiung , Chen Wen‐Chau , Wu Tseng‐Rong
Published: June 2015

A new lignan, formosanol, has been isolated from Juniperus formosana Hayata and elucidated as formula (5a) by spectra and chemical evidences.
Indo‐Mo Model with s·p Separation
Authors: Chen Cheng , Ellison Frank O. , Chang Mingtzon , Chou Jinlung
Published: June 2015

A newly developed self‐consistent‐field molecular orbital theory is described and tested. The intermediate neglect of differential overlap (INDO) approximation is used, and all interaction integrals are differentiated according to their dependence upon 2s and 2p AO's. The bonding parameter βl is reformulated so that the model is calibrated to only one specific molecular property, namely, the ionization energy of Hi. We expect that this model will not be biased toward any special families of molecules.
Catalytic Spectrophotometric Determination of Vanadium by Flow Injection Analysis
Authors: Hwang J.M. , Tsung J.C. , Chen Y.M.
Published: June 2015

Determination of trace amount of vanadium in water was studied by flow injection analysis. Catalytic spectrophotometric detection was performed with bromate oxidation of o‐phenylenediamine and by addition of tiron as an activator and also as a masking agent. Vanadium can be determined with sample rate of ca. 60–70 samples/hour with in a range of 0.01 ppm to 0.5 ppm V and with r.s.d. 0.555% for 0.1 ppm V and 0.37% for 0.3 ppm V. Interference by Fe(III) can be reduced by using 0.3% NH4F as a carrier solution.
Synthesis and Characterization of Bridged Bimetallic Complexes. I. Copper(II) Complexes with Conjugated Diimine Ligands
Authors: Wang Wen‐Jwu , Ho Chia‐Tai
Published: June 2015

A series of binucleating Uganda with fully conjugated π‐systems have been synthesized. Homobinuclear copper(II) complexes of the form [(Cu(dien)ClO4)2L]‐(ClO4)2, where dien is diethylenetriamine and L is binucleating ligand, were prepared. Mononuclear complexes, with structure similar to that of the preceeding compounds, [Cu(dien)L′(ClO4)](ClO4) were synthesized as reference compounds. The infrared spectra, elctronic spectra and magnetic properties were studied. The inductive effect, steric effect and the effect of the length of the conjugated π‐system on the magnetic exchange interaction between the two copper ions are discussed. The electrochemical properties of these complexes were investigated by cyclic voltammetry. The copper ions showed the cooperative phenomena and a quasi‐reversible sequential transfer of two electrons at the same potential.
Kinetic Studies of the Catalytic Effect of Cobalt(II) Ions on the Substitution Reactions of the Ethylenediaminetetraacetatocobalt(III) Complex
Authors: Yu Joyce , Tung Hui‐Chan , Yeh Andrew
Published: June 2015

The rate for the substitution reaction of Co(edta)− with ethylenediamine was greatly enhanced by the presence of an excess of Co(II) ion in solution. The rate constant is (13±2) M−‐sec−1 at μi=0.10M LiClO4, pH=11.1, [en]=0.10M and T=25°C. The mechanism for the reaction is discussed on the basis of the Marcus theory for outer‐sphere processes corrected for electrostatic effects. This catalytic effect was not observed when the Co(II) was present in small amount due to the stability of the Co(edta)−2 complex toward substitution. The rate constant for direct substitution of Co(edta)− under the same conditions has also been measured and the value is (3.66±0.40)×10−4sec−.
Photochemical Synthesis and Characterization of 8,9‐Dihydroacenaphtho‐[1,2‐b][1,4]Dioxins
Authors: Fang Tai‐Shan , Mei Wang‐Ping , Chang Tsing‐Hsing , Shih‐Chen S.J.
Published: June 2015

The orange‐red 8,9‐dihydroacenaphtho[1,2‐b] [1,4]dioxins were synthesized by the photo‐Diels‐Alder reaction of acenaphthenequinone with the corresponding alkenes. The products were characterized by spectroscopic and X‐ray methods.
A New Synthesis of 2‐(6‐Methoxycarbonylhexyl)‐Cyclopent‐2‐EN‐1‐One Using α‐Silylallyl Sulphide
Authors: Chen Ling‐Ching , Wu Shihn‐Sheng
Published: June 2015

Acylation of the α‐trimethylsilylallyl phenyl sulphide (2). by reaction with the acid chloride (3), catalyzed by aluminium chloride in CH2Cl2 at −78°C, gave methyl 9‐oxo‐12‐phenylthio‐11‐dodecene (4). Hydrolysis of (4) followed by aldol condensation gave 2‐(6‐methoxycarbonylhexyl)‐cyclopent‐2‐en‐1‐one (6).
Structural Relationships between the Hemiporphyrazine Macrocyclic Ligand and its Metal Complexes. II.: Planar Neutral Ligand, C26H16N8, and Four Isomorphous Metal Complexes, [M(C26H16N8)(H2O)], M=Mn(II), Co(II), Cu(II), Zn(II)
Authors: Peng Shie‐Ming , Wang Yu , Chen Chun‐Kuei , Lee Jang‐Yen , Liaw Der‐Shin
Published: June 2015

Crystal and molecular structures of the planar neutral ligand, C26H16N8, and the four isomorphous five‐coordinated metal complexes, [M(C26H16N8)(H2O)], M = Mn(II), Co(II), Cu(II), Zn(II), have been determined from three‐dimensional X‐ray diffraction data. The free ligand hpH2, C26H16N8, belongs to the P 21/c space group with Z=2, a=4.142(3), b=23.736(6), c=10.338(3) Ä, β=94.66(6)°. The metal complexes monohydrate Mhp‐H2O all belong to the orthorhombic Pcab space group with Z=8. The dimensions are roughly 8.8×19.3×23.7 Å3. In each structure, the macrocyclic ligand has an almost planar conformation which differs from the saddle shaped ligand hydrate (hpH2·H2O) and the nickel complex [Nihp]5. The distances from the center of the macrocyclic ring to the nitrogen atom of the free ligand are 1.907(6) and 2.245(6)Å. The coordination geometry in these four complexes is square pyramidal with a water molecule as an axial ligand. The bond distances of M(II)‐O(H2O), M(II)‐N1 (imine), M(II)‐N3 (pyridine) are: 2.19(1), 2.00(2), 2.27(2)Å respectively for the manganese complex; 2.08(1), 1.97(1), 2.23(1)Å for the cobalt complex; 2.33(1), 1.92(3), 2.18(1)Å for the copper complex; 2.110(5), 1.964(6), 2.252(6)Å for the zinc complex. The variation of metal‐ligand distances can be correlated to the metal d orbital occupancy. A comparison with similar ligands will be presented.
A New Calibration Method for the Gel Permeation Chromatographic Fractionation of Polymers
Authors: Su Shyh‐Gong , Mou Chung Yuan
Published: June 2015

A model for the mechanism of the Gel permeation chromatographic separation of a polymer and a new calibration method have been developed, based on the exclusion of the polymer from the pores of the packing material. We propose that the calibration curve a plot of log (1—√K) versus log (molecular weight), where K is the elution volume coefficient, is close to linear over a K range of 0.15–0.85. We compare our procedure with that of Haller for various sets of data. Our procedure is generally better with lower standard deviations. When extrapolated, it gives a critical permeation size characteristic of the glass column packings.
Cycloaddition Reactions of 3,5‐DI‐t‐Butyl‐o‐Benzoquinone and Masked 3,5‐DI‐t‐Butyl‐o‐Benzoquinones with Substituted Acetylenes)
Authors: Liao Chun‐Chen , Lin Ho‐Shen
Published: June 2015

Cycloadditions of 3,5‐di‐t‐butyl‐o‐benzoquinone with diphenylacetylene, dimethyl acetylenedicarboxylaet, 3‐hexyne, phenylacetylene, methyl propiolate, 1‐octyne and 3‐hydroxy‐3‐methyl‐1‐butyne were studied. The reactions occur periselectively across the diene moiety of 3,5‐di‐t‐butyl‐o‐benzoquinone to give bicyclo[2.2.2]octa‐5,7‐diene‐2,3‐diones. In the cases of monosubstituted acetylenes, the reactions take place regioselectively. The selectivities are explained in terms of electronic and steric effects.

The cycloadditions of two masked 3,5‐di‐t‐butyl‐o‐benzoquinones 7 and 8 with monosubstituted acetylenes, phenylacetylene, methyl propiolate, 1‐octyne and 3‐hydroxy‐3‐methyl‐1‐butyne were also examined. Compound 7 reacts with high regioselectivity to give only bicyclo[2.2.2]octa‐5,7‐diene‐2,3‐diones 10 upon subsequent hydrolysis; the high regioselectivity was explained as the result of coherent electronic and steric effects. Compound 8 reacts with monosubstituted acetylenes to give either 9 or 10 or both upon subsequent hydrolysis, depending on the nature of the substituents on acetylene. This results from the opposite influences of electronic and steric effects.
Preparation of Cis‐Enediones from Furans by Photooxidation
Authors: Kuo Yueh‐Hsiung
Published: June 2015

Photooxidation of furan derivatives followed by reduction with methyl sulfide affords cis‐enediones in excellent yields.
EPR Studies of (3, 5‐di‐t‐Butyl‐0‐Benzoquinone) Tetracarbonylrhenium(0) Radical
Authors: Cheng C. P. , Wang S. R. , Chou T. C.
Published: June 2015

The organometallic radical: (3,5‐di‐t‐butyl‐0‐benzoquinone)tetracarbonyl‐rhenium(0) and its triphenylphosphine substituted derivatives were studied by EPR spectroscopy. The unpaired electron is shown to be localized in the organic 1,2‐diketone ligand. The rate of carbonyl substitution by triphenylphosphine at the unsubstituted rhenium radical indicates a second order reaction. The activation parameters are ΔH* =19.1±0.8Kcal/mole and ΔS*‐3.0±1.5 eu/mole.