bluuebunny/crossref_metadata_2025_split huggingface dataset:
Furanocoumarins and Sesquiterpene Ketone from Clausena Lansium Skeels
Authors: Li Wen‐Shyong , McChesney James D. 
Published: June 2015

AbstractThree known furanocoumarins, imperatorin (1), wampetin (dehydroindicolactone) (2) and 8‐geranoxypsoralen (3) and a new sesquiterpene ketone, (+)‐oplopanone (4), were isolated from Clausena lansium Skeels. The stereochemistry of the last two coumarins was determined by NOESY experiments. The idendity of (+)‐oplopanone was established by comparison of its physical constants and spectroscopic data with those reported for its enantiomer as well as a comparison of its' TLC behavior with that of an authentic sample.
Synthesis and Primary Photoreaction of C18‐Methyl‐β‐Ionylidenemalononitrile
Authors: Yao‐Pinyen  , Lew Miaw‐Chun 
Published: June 2015

AbstractA synthesis of C18‐methyl‐β‐ionone (8) and C18‐methyl‐β‐ionylidenemalononitrile (13) is reported. Photoreaction of C18‐methyl‐β‐ionylidenemalononitrile resulted in a reversible 7‐cis and 7‐trans isomerization which eventually underwent 1,5‐Hydrogen shift to give the irreversible photoproduct, C18‐methyl‐y‐retro‐ionylidenemalononitrile (14).
The Difference in the Behaviour of Hydrazine and p‐Substituted Phenylhydrazines on Various 4‐(3‐Aryl‐3‐Oxopropenyl) Antipyrines
Authors: El‐Khawass S.M. , Farghaly A.M. , Chaaban I. , Fahmy S.M. 
Published: June 2015

AbstractA series of novel 4‐(3‐aryl‐4,5‐dihydro‐lH‐pyrazol‐5‐yl)‐l, 5‐dimethyl‐2‐phenyl‐lH‐pyrazol‐3(2H)‐oncs (III) were synthesized. Thus, the key intermediates, 4‐(3‐aryl‐3‐oxopropenyl‐1,5‐ dimethyl‐2‐phenyl‐1H‐pyrazol‐3(2H)‐ones (II) were cyclized with hydrazine hydrate containing a few drops of ethanol gave the desired pyrazoline derivatives (III), which can be acetylated to afford the target N‐acetyl derivatives (IV). On the other hand, the same reaction condition using p‐substituted phenylhydrazines, the starting key intermediates (II) were recovered unchanged. The use of glacial acetic acid instead of ethanol, lead to a new series of 1,3‐diarylpyrazoles (VI) by a different pathway. The structure of the newly synthesized compounds was elucidated by elemental analyses, IR, 1H‐NMR and mass spectra.
Synthesis of 4‐Arylpyridines for Intramolecular Cyclization Studies I.
Authors: Shjao Min‐Jen , Perng Cherng‐Yih , Chiu Cheng‐Tung , Liang David 
Published: June 2015

Abstract4‐Arylpyridines 4a‐4h arc synthesized in good yield by the addition of Grignard reagents or organolithium derived from bromobenzene derivatives 2a‐2h in the presence of catalytic amount of cuprous iodide to N‐ethoxycarbonylpyridinium choloride la‐lh followed by oxygen oxidation.
Ring‐Cleavage Reactions of Five‐ and Six‐Membered Cyclic Ethers with Organolithium Compounds
Authors: Chou Ta‐Shue , Hung Shao‐Hwa , Cheng Chien‐Chung 
Published: June 2015

AbstractIn the presence of one equivalent of boron trifluoride etherate, organolithium compounds cause the ring cleavage reactions of tetrahydrofurans and tetrahydropyran to give the corresponding long‐chain alcohols in moderate yields. These reactions are highly regioselective for unsymmetric cyclic ethers.
Relaxation Studies of 2IZSZ Spin Order in Liquid Benzene: Selection of Chemical Shift Anisotropy Parameters
Authors: Chang Chi‐Fon , Hwang Lian‐Pin 
Published: June 2015

AbstractThe effects of cross‐correlation of chemical shift anisotropy and dipole‐dipole interactions result in the relaxation of 2IzSz spin order. The intensity of relaxation profile is sensitive to the variation of chemical shift anisotropy interactions. With spin‐rotation interaction taken into consideration, it has been successfully applied to the selection of appropriate sets of chemical‐shift anisotropy parameters for benzene.
Correlation of Solvolytic Reactivities. A New YBnBr Scale for Benzylic Bromides
Authors: Liu Kwang‐Ting , Sheu Hun‐Chang 
Published: June 2015

AbstractSolvolysis of 2‐bromo‐2‐(4′‐fluoromethyl)phenyladamantane (4), and 2‐bromo‐2‐(4′‐trifluoromethyl)phenylpropane (5) were carried out in a number of solvents, and their rate constants measured. Significant deviation from linear logk‐YBr plots was observed, and the order of reactivities, e.g., k(100M) > k(90E) > k(80A), was in the reverse order of Swain's solvent parameter B. Different extent of solvation to the localized and the delocalized cationic transition state was then likely to play an important role. Similar result was also found in the solvolysis of 1‐bromo‐2,2,2‐trifluoro‐1‐(4′‐methylphenyl)‐1‐phenylethane (6). A new Y scale, YBnBr, for the correlation of solvolytic reactivities of benzylic bromides based on k(4) was established. Intervention of solvent assistance in the solvolysis of 5 is discussed.
Studies of Intramolecular Cyclization of 4‐Arylpyridines. II Syntheses of Condensed Tricyclic Pyridines
Authors: Shiao Min‐Jen , Perng Cherng‐Yih , Shen Chien‐Chang 
Published: June 2015

AbstractA convenient method for the synthesis of condensed tricyclic pyridines using intramolecular cyclization of 4‐arylpyridines is reported. The tricyclic compounds, 2‐azafluorenone (9), 2‐azafluorenone (10), 2‐azafluorenol (11), lactones 12 and 13, and anhydride 14 have been prepared.
New Esters, 2‐(4‐Hydroxy‐3‐Methoxyphenyl)Ethyl Hexa‐ and Octacosanoates from the Leaves of Cinnamomum Reticulatum Hay
Authors: Kuo Yueh‐Hsiung , Shue Ming‐Jeng 
Published: June 2015

AbstractThe leaves of Cinnamomum reticulatum Hay were extracted successively with hexane and acetone successively. Dipentadecyl ketone, n‐dotriaconyl alcohol, 2‐(4‐hydroxy‐3‐methoxyphenyl)ethyl hexa‐ and octacosanoates ( two new esters from hexane extract ), β‐sitosterol, fatty acid, vanillin, p‐hydroxybenzaldehyde, genkwanin, vanillic acid, p‐hydroxybenzoic acid, β‐sitosteryl‐l‐β‐glucopyranoside, meso‐erythritol, glucose, and 4‐(2‐hydroxyethyl)‐2‐methoxyphenyl‐l‐β‐D‐glucopyranoside (from the acetone extract) were isolated. The structures of the new esters were elucidated by chemical and physical evidence.
Studies on the Constituents of Ganoderma Lucidum
Authors: Chiang Hung‐Cheh , Chu Shih‐Chang 
Published: June 2015

AbstractThe methanolic extract of fruit bodies of cultivated Ganoderma lucidum was separated by silica gel column chromatography and preparative thin‐layer chromatography to give ten compounds. On the basis of spectral analysis, chemical procedures and gas chromatography, d‐mannitol (1), ergosta‐7, 22‐dien‐3β‐yl palmitate (2), ergosterol (3), ergosta‐7, 22‐dien‐3β‐ol (4), 5α‐lanosta‐7,9(11),24‐trien‐3β,26‐diol (5), ergosterol peroxide (6), 24,25,26‐trihydroxy‐5α‐lanosta‐7,9(11)‐dien‐3‐one (7), 5α‐lanosta‐7,9(11)‐dien‐3β,24,25,26‐tetraol (8) and 8,9‐epoxyergosta‐5,22‐dien‐3β,15‐diol (9) were identified. Among these compounds, 8,9‐epoxyergosta‐5,22‐dien‐3β,15‐diol was first separated from Ganoderma lucidum.
Enhancement of Chemical Reactions by Microwave Irradiation
Authors: Chen Shui‐Tein , Chiou Shyh‐Horng , Wang Kung‐Tsung 
Published: June 2015

AbstractMicrowaves are low electromagnetic energy which induce molecular perturbation by stimulation of ionic diffusion and by enhancement of dipole rotation without causing rearrangement of molecular structures. Microwave energy irradiated on the samples in various liquid media is lost or absorbed to the samples by the following two mechanisms: ionic conduction and dipole rotation. These two effects take place simultaneously to account for the phenomenon of rapid heating associated with many practical applications of microwave irradiation. In contrast to conventional heating, the salient feat ure of “dipole rotation” constitutes one efficient form of “molecular agitation” or “molecular stirring” which can be explored for many aspects in chemical reactions. We will discuss some of the useful application of “molecular agitation” by means of microwave irradiation such as: 1. rapid hydrolysis of proteins and peptides, 2. selective hydrolysis of aspartyl peptide bond, 3. the racemization of amino acids, 4. rapid hydrolysis of sugars, 5. continuous‐flow process of microwave reactions, and 6. the enhancement of coupling reactions in peptide synthesis.
Kinetic Studies of Chromic Acid Oxidation of Glyoxal
Authors: Lin Tzuen‐Yeuan , Mao Yuh‐Lin , Chuo Chih‐Ming 
Published: June 2015

AbstractThe kinetics of chromic acid oxidation of glyoxal is reported. The reaction is first‐order in glyoxal and indicates a gradual change from a first‐order to a zero‐order dependence on acidity. The kinetic nature of this reaction has been studied and the rate law is consistent with a proposed mechanism as follows; rate = kKb, K[Cr+6][Gx][H+]/(l+0.238[H+]) at 25°C. The product analysis indicates that formic acid is the oxidation product under similar kinetic condition.
A Modified Water‐Gas Shift Reaction. The Decomposition of Alkyl Formate in the Presence of Water Using a Ruthenium Carbonyl
Authors: Jou Der‐Ching , Cheng Chien‐Hong 
Published: June 2015

AbstractAlkyl formates in the presence of water were rapidly decomposed to H2, CO2 and the corresponding alcohols using Ru3(CO)12 and KOAc as catalyst. Based on the hydrogen gas produced, a turnover rate as fast as 8446/h for ethyl formate at 140°C was observed. The catalyst system was also active for the decomposition of other alkyl formates. The rate of decomposition increased both with increasing amount of KOAc and with decreasing number of carbon atom in the alkyl group of the formate. In addition to Ru3(CO)12, several other transition metal complexes RuCl3, RuCl2(PPh3)3, Os3(CO)12, H2Os3(CO)10, RhCl3, and RhCl(PPh3)3, were active in the catalytic decomposition of alkyl formates, although their activities varied greatly. The Ru3(CO)12‐KOAc system also catalyzed the reduction of nitrobenzene by HCOOEt‐H2O to aniline in EtOH and to a mixture of N‐phenylformamide and N‐methyl‐N‐phenylformamide in HCOOEt. Under coditions the same as for the hydrogenation of nitrobenzene, ethylene styrene and cyclohexenone were reduced to the corresponding alkanes, whereas 1‐hexene and 1‐octene were isomerized to the corresponding 2‐alkene products.
The Flash Vacuum Thermolysis ofN‐Acyl Imidates
Authors: Wu Pei‐Lin , Wang Ching‐Cheng 
Published: June 2015

AbstractIn the flash vacuum thermolysis of methylN‐acyl imidates, the loss of methanol is consistent with the intermediacy of anN‐acylketenimine. Recombination and further reactions may lead to the array of products observed in these thermal reactions. An attempt to trap the intermediateN‐acylketenimine by an intramolecular [2 + 2] cycloaddition was unsuccessful.
Synthesis of Some Pyrimidine 2‐Oxo(Thio)‐4,6‐Dione Derivatives
Authors: El‐Badawi M. , Ibrahim E. S. I. , Farag H. , Abbasi M. M. 
Published: June 2015

Abstract5‐Arylidenes 1a and 1b, on reaction with ethyl cyanoacetate and diethyl malonate in the presence of ammonium acetate under Michael condensation, yield pyridine derivatives 2 and 3, respectively. Cyclopentapyrimidine derivative 4 can also be obtained by the reaction of 1a with malononitrile in the presence of piperidine. The reaction of 5‐arylidene lb with monochloroacetic acid in an alkaline medium gives the thiazol derivative 5. Also, spiro‐[3′, 5′]cyclohexenyl pyrimidine derivative 6 could be obtained from the reaction of 1d with maleic anhydride. On the other hand, 5‐arylidene 1e reacts with maleic anhydride to give 2‐thiobarbituric acid derivative 7. The condensation reaction of 2‐thiovioluric acid 8 with some hydrazines affords the triazole derivatives 9a‐d. Finally, barbituric acid condenses with isatin to give 5‐arylidene 1f, which can be cyclized with phosphorous pentoxide to afford 10.
Synthesis of Some Antimicrobial Purine Nucleoside Derivatives
Authors: Ahmed A. F. Sayed , Rahman S. Abdel , Hamad M. M. , Hattaba A. A. 
Published: June 2015

AbstractSome N(6)‐substituted adenosine derivatives and adenosine attached to different amino‐acid residues and peptides at position 8 have been synthesized using improved methods. The biological activities of the prepared compounds towards gram‐positive and gram‐negative bacteria are described.
New Approaches to Absorption Detection in Capillary Chromatography and Capillary Electrophoresis
Authors: Yeung Edward S. 
Published: June 2015

AbstractTwo new approaches for absorption detection in capillary columns are presented. They are applicable to columns as narrow as 10μm i.d. Both provide good sensitivity despite the very short optical pathlengths that are commonly available in commercial systems. The first involves irradiating the column along its axis rather than across the axis. The entire analyte zone can then participate in absorption. Gains up to 1000 fold can be expected. The second is a modification of laser‐excited fluorescence. The absorbing analytes, even though they do not fluoresce efficiently, can transfer their energy to a fluorophore added to the mobile phase. The secondary emission can be used to detect absorption in the nanomolar range.
An Ultrasonic Nebulizer as the Sample Introduction Device for High Performance Liquid Chromatography Combined with Inductively Coupled Plasma Atomic Emission Spectrometry
Authors: Wang Su‐Ru , Jiang Shiuh‐Jen 
Published: June 2015

AbstractA preliminary study of an ultrasonic nebulizer as the sample introduction device for the chromatographic speciation of ionic compounds containing As, Se and Cr is described. The analytical figures of merit observed during chromatographic separations with an ultrasonic nebulizer interfaced to an inductively coupled plasma‐atomic emission spectrometer (ICP‐AES) were comparable to or better than conventional pneumatic nebulization and other sample introduction techniques, in terms of organic solvent tolerance, sensitivity, detection limits and reproducibility. The limits of detection were in the ranges of 10‐14 ppb for Se, 30‐40 ppb for As, and 8‐10 ppb for Cr.
Kinetics and Mechanism of the Cerium(IV) Oxidation of Arnold's Base and the Protonation and Hydroxylation of Michler's Hydrol Blue
Authors: Wu Rong Tay , Jwo Jing‐Jer 
Published: June 2015

AbstractIn aqueous H2SO4, Ce(IV) ion oxidizes rapidly Arnold's base((p‐Me2NC6H4)2CH2, Ar2CH2) to the protonated species of Michler's hydrol((p‐Me2NC6H4)2CHOH, Ar2CHOH) and Michler's hydrol blue((p‐Me2NC6H4)2CH+, Ar2CH+). With Ar2CH2 in excess, the rate law of the Ce(IV)‐Ar2CH2 reaction in 0.100 M H2SO4 is expressed ‐d[Ce(IV)]/dt = kapp[Ar2CH2]0[Ce(IV)] with kapp = 199 ± 8M−1s−1 at25°C. When the consumption of Ce(IV) ion is nearly complete, the characteristic blue color of Ar2CH+ ion starts to appear; later it fades relatively slowly. The electron transfer of this reaction takes place on the nitrogen atom rather than on the methylene carbon atom. The dissociation of the binuclear complex [Ce(III)ArCHAr‐Ce(III)] is responsible for the appearance of the Ar2CH+ dye whereas the protonation reaction causes the dye to fade. In highly acidic solution, the rate law of the protonation reaction of Michler's hydrol blue is ‐d[Ar2CH+]/dt = kobs[Ar2CH+] where Kobs = ((ac + 1)[H*] + bc[H+]2)/(a + b[H+]) (in HClO4) and kobs= ((ac + 1 + e[HSO4−])[H+] + bc[H+]2 + d[HSO4−] + q[HSO4−]2/[H+])/(a + b[H+] + f[HSO4−] + g[HSO4−]/[H+]) (in H2SO4), and at 25°C and μ = 0.1 M, a = 0.0870 M s, b = 0.655 s, c = 0.202 M−1s−1, d = 0.110, e = 0.0070 M−1, f = 0.156 s, g = 0.156 s, and q = 0.124. In highly basic solution, the rate law of the hydroxylation reaction of Michler's hydrol blue is ‐d[Ar2CH+]/dt = kOH[OH−]0[Ar2CH+] with kOH = 174 ± 1 M−1s−1 at 25°C and μ = 0.1 M. The protonation reaction of Michler's hydrol blue takes place predominantly via hydrolysis whereas its hydroxylation occurs predominantly via the path of direct OH attack.
Axial and Equatorial Substitution of Dimethylamine on Phosphorus in the 1,3,2‐Oxazaphosphorinane Ring System: Structures of 2‐Dimethylamino‐Phenyl‐2H‐1,3,2‐oxazaphosphorinane‐2‐Oxides
Authors: Shih Yun‐Er , Liu Yi‐Fang , Wang Jy‐Shih , Liu Ling‐Kang 
Published: June 2015

AbstractX‐ray structures of trans‐2‐dimethylamino‐5‐phenyl‐2H‐1,3,2‐oxazaphosphorinane‐2‐oxide, 5b, and trans‐2‐dimethylamino‐6‐phenyl‐2H‐1,3,2‐oxazaphosphorinane‐2‐oxide, 6c, have been determined. These two compounds have been prepared in a straightforward manner by a reaction of cyclization of Mc2NP(O)Cl2 with the corresponding 3‐amino‐2‐phenylpropanol and 3‐amino‐1‐phenylpropanol, respectively, to produce (5b, 6b) and (5c, 6c), and were separated into pure forms by chromatography. Crystal data of 5b: space group Pccn, a = 10.675(5), b = 31.685(9), c = 7.217(3) Å, R = 0.065 for 1040 reflections. Crystal data of 6c: space group P‐1, a = 9.803(6), b = 12.455(5), c = 12.690(2) Å, α = 114.11(2), β = 80.88(2), γ = 111.64(4)°, R = 0.035 for 3534 reflections. For the pair 5b and 6b, the slowly‐migrating 5b is trans (Ph and P = O group trans) with the configuration of 2RS, 5RS, hence 6b is the cis isomer. For the pair 5c and 6c, the slowly migrating 6c is trans with the configuration of 2RS, 6SR; hence 5c is the cis isomer. In both X‐ray structures the 1,3,2‐oxazaphosphorinane rings are chair‐like with the P‐end essentially flattened. With a conformationally demanding 5‐phenyl substituent, 5b has an axial Me2N whereas with also a conformationally demanding 6‐phenyl substituent, 6c has an equatorial Me2N. For 6c, the exocyclic P‐N bond has partial double bond character: the geometry about exocyclic N is planar. On the other hand, for 5b, the geometry about exocyclic N deviates considerably from planarity, the sum of the angles around N being 343.3°. In the crystalline state, the two crystallographically independent molecules of 6c are linked together in a hydrogen‐bonded system involving the water molecule.
Preparations of Chiral Menthyl α‐Sulfinylacrylates. The Optically Active Dienophiles with Double Asymmetric‐Induction Capability
Authors: Yang Teng‐Kuci , Teng Tsung‐Fan , Lec Dong‐Sheng 
Published: June 2015

AbstractThe introduction of optically active carboxylates onto the chiral vinyl sulfoxides increased their reactivities toward electron‐rich dienes in Diels‐Alder cycloadditions, thus much milder reaction conditions were used. The two chiral auxiliaries became cither a matched or mismatched pair which can be justified by their ability of chiral induction. Here we report a preparative‐scale synthesis of optically active α‐sulfinylacrylates with double asymmetric capability.
Interfacial Electrochemical Behavior of RuS2 Single Crystal Electrodes in Sulfuric Acid Medium
Authors: Sheu Jiang‐Shing , Shih Yen‐Shiang , Huang Ying‐Sheng 
Published: June 2015

AbstractThe electrochemical behavior of RuS2 has been studied using cyclic voltammetry and Energy Dispersive X‐ray Spectroscopy (EDX) techniques. Cyclic voltammograms reveal one major anodic peak and two major cathodic peaks on the reverse sweep; these peaks are attributed to the electroadsorption/desorption of OH− groups on the electrode surface. It is proposed that the electroadsorption of the OH− group on RuS2 is due to the presence of Ru 4d electrons in the uppermost part of the valence band. Thus, OH− is oxidized by holes on Ru 4d states in the first step. These groups are transferred to S22−sites in the second step. EDX surface analysis reveals preferential release of S22− from the pyrite lattice. A mechanism for the anodic dissolution of RuS2 is proposed, according to which elemental sulfur is not a direct product, but rather the end product which forms from thiosulfate.
UV/VIS Spectral Studies of Catecholase Activity of Binuclear Copper(II) Complexes [Cu2REP(μ‐X)(Y)2]
Authors: Chyn Jong‐Pyng , Chou Jeh‐Li , Shieh Kuan‐Jiunn 
Published: June 2015

AbstractBy means of ultraviolet and visible spectroscopy we have studied the catecholase activity of two binuclear copper(II) complexes of general formula [Cu2REP(u‐X)(Y)2] (1, X=OH and Y=ClO4; 2, X=Y=CI), REP =deprotonated 2, 6‐bis(1′‐(4′‐(2″‐pyridyl)‐2′‐thiabutyl))‐4‐methylphenol. Both complexes promote catalytic autoxidation of 3, 5‐di‐tert‐butylcatechol (3, 5‐DTBC) to 3, 5‐di‐tert‐butylquinone (3, 5‐DTBQ) in methanol, but not in acetonitrile.
3‐Substituted Sydnone Derivatives. Structures of 3‐Cyclohexylsydnone and of Two Forms of 3‐(3‐Pyridyl)sydnone
Authors: Rychlewska Urszula , Hodgson Derek J. , Yeh Andrew , Tien Hsien‐Ju 
Published: June 2015

AbstractThe crystal and molecular structures of three sydnone derivatives are reported. The compound 3‐cyclohexylsydnone crystallizes in space group C2/c of the monoclinic system with sixteen molecules in a cell of dimensions a = 19.326 (3), b = 9.471 (2), c = 20.005 (4)Å, β = 106.85(1)°. The structure has been refined to a final value of 0.0581 for the conventional R‐factor based on 2222 independent observed intensities. Form I of 3‐(3‐pyridyl)sydnone crystallizes in space group P2/n of the monoclinic system with eight molecules in a cell of dimensions a = 7.317(2), b = 9.283 (2), c = 20.891 (6) Å, β = 99.61(2)°. The structure has been refined to a final value of 0.0514 for the conventional R‐factor based on 1208 independent observed intensities. Form II of 3‐(3‐pyridyl)sydnone crystallizes in space group P21/c of the monoclinic system with eight molecules in a cell of dimensions a=9.073 (2), b = 22.267 (5). c = 7.494(2)Å, β = 112.15 (2)°. The structure has been refined to a final value of 0.0462 for the conventional R‐factor based on 1330 independent observed intensities. Each of the three structures contains two crystallographically independent molecules in the cell. In the case of 3‐cyclohexylsydnone, one of the independent molecules exhibits disorder around the exocyclic bond at N(3). A comparison of bond lengths indicates that the (electron donating) cyclohexyl group brings about enhanced electron density in the N(3)‐C(4) bond, and possibly in the N(3)‐N(2) bond. All three structures studied here exhibit intermolecular hydrogen bonding involving C(4)‐H(4)…O(6) interactions. Although there are no stacking interactions in the cyclohexyl derivative, there is evidence for such interactions in the 3‐pyridyl derivatives.
Intramolecular Diels‐Alder Reactions via 3‐(Phenylthio)‐4‐(Trimethylsilyl)‐3‐Sulfolene
Authors: Chou Shang‐Shing P. , Lee Chien‐Ming 
Published: June 2015

AbstractDeprotonation of the title compound 2 followed by treatment with 5‐iodo‐1‐pentene or 6‐iodo‐l‐hexene gave the alkylated products 3 and 4 which upon refluxing in toluene yielded the dienes 8a and 8b. Intramolecular Diels‐Alder reactions were achieved by heating the dienes 8a and 8b in toluene in a sealed tube at 160–180°C to give bicyclo[4.3.0]nonene 9 and bicyclo[4.4.0]decene 10, respectively, in good yield. The stereochemistry of the cyclization products was determined, and was rationalized by comparison of the possible transition states involved.
Theoretically Calculated Deformation Density of Small Molecules
Authors: Lin Kuan‐Jiuh , Wang Chih‐Chieh , Wang Yu 
Published: June 2015

AbstractAnalysis of the theoretical electron deformation density based on EHMO and ab initio calculations has been applied to the simple molecules F2, H2O and SO2 The effects from varied basis sets for such deformation density were sought. The accumulation of electron density between the bonded atoms calculated from EHMO and ab initio methods with STO‐3G is generally under‐estimated. Such phenomena are significantly improved by using split‐valence basis sets e.g. 3–21G and 4–31G. The addition of d polarization functions is apparently important for the sulfur atom in sulfur‐related bonding. 3–21G or 3–21G* basis sets were found to provide not only valuable deformation density distributions of molecules but also comparable orbital energy states with respect to the experimental values.