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Articles 31 - 60 of 60
Full-Text Articles in Organic Chemistry
Boron Phosphate And Aluminum Phosphate Aerogels, David A. Lindquist, Steven M. Poindexter, Sterling S. Rooke, D. Ritchie Stockdale, Kirk B. Babb, Alison L. Smoot, William E. Young
Boron Phosphate And Aluminum Phosphate Aerogels, David A. Lindquist, Steven M. Poindexter, Sterling S. Rooke, D. Ritchie Stockdale, Kirk B. Babb, Alison L. Smoot, William E. Young
Journal of the Arkansas Academy of Science
Anhydrous sol-gel condensation of triethyl phosphate [(CH3CH2O)3PO] with boron trichloride (BCL3 ) or triethyl aluminum [(CH3CH2 ) 3A1] in organic solvents, led to formation of metallophosphate gels. The pore fluid of the gels was removed under supercritical conditions in a pressurized vessel to form aerogels. The aerogels were then calcined at progressively higher temperatures to produce high surface area phosphates. Since the initial gel reagent mixtures contained several NMR active nuclei, the condensation chemistry prior to the gel point was monitored by solution nB NMR. The surface areas, distribution of pore sizes, and total pore volumes of the aerogel products …
Hammett Correlations Of Half-Wave Reduction Potentials In A Series Of N-(Aryl Substituted)-Dichloronicotinamides, Cecil C. Persons, Ali U. Shaikh, Julie Shiflett, Frank L. Setliff
Hammett Correlations Of Half-Wave Reduction Potentials In A Series Of N-(Aryl Substituted)-Dichloronicotinamides, Cecil C. Persons, Ali U. Shaikh, Julie Shiflett, Frank L. Setliff
Journal of the Arkansas Academy of Science
Excellent correlations of Hammett substituent constants (sigmaR) of a series of N-(R-substituted aryl) -2,6-, 2,5-, and 5,6- dichloronicotinamides with polarographic half-wave potentials were observed. Although the correlations demonstrate that all three series of amides experience comparable sensitivity to the R groups at the carbonyl reduction site, the relative ease of reduction varies according to the chlorine substitution pattern on the pyridine ring. These differences are suggested to be due to combinations of mesomeric, inductive, and field effects which operate differently in the three systems. Correlation analysis also revealed that Hammett heteroatomic replacement constants previously determined by NMR studies are valid …
Ultrasound Assisted Oxidative Cleavage Of Alpha-Keto, Alpha-Hydroxy And Alpha-Halo Ketones By Superoxide, Yi Hong Cao, A. Toland, Dominic T.C. Yang
Ultrasound Assisted Oxidative Cleavage Of Alpha-Keto, Alpha-Hydroxy And Alpha-Halo Ketones By Superoxide, Yi Hong Cao, A. Toland, Dominic T.C. Yang
Journal of the Arkansas Academy of Science
No abstract provided.
Suppression Of The Oxidation Of S(Iv) In Rainwater, David M. Chittenden Ii
Suppression Of The Oxidation Of S(Iv) In Rainwater, David M. Chittenden Ii
Journal of the Arkansas Academy of Science
No abstract provided.
Microscale Preparation Of Pyrocatechol: The Use Of Sodium Percarbonate In The Dakin Reaction, T. Evans Yamazaki, Dominic T.C. Yang
Microscale Preparation Of Pyrocatechol: The Use Of Sodium Percarbonate In The Dakin Reaction, T. Evans Yamazaki, Dominic T.C. Yang
Journal of the Arkansas Academy of Science
No abstract provided.
Determination Of Hammett Pyridine 3-Aza And 4-Aza Replacement Constants By 1h Nmr Studies Of Amide Systems, Frank L. Setliff, Nikhil G. Soman, Alan D. Toland
Determination Of Hammett Pyridine 3-Aza And 4-Aza Replacement Constants By 1h Nmr Studies Of Amide Systems, Frank L. Setliff, Nikhil G. Soman, Alan D. Toland
Journal of the Arkansas Academy of Science
Values for Hammett pyridine 3-aza and 4-aza replacement constants were obtained by correlation of the amide proton chemical shifts (in DMSO) of some N-(3-pyridyl)-and N-(4-pyridyl)-dichloronicotinamides, benzamides and acetamides with those of their N-(substituted phenyl) amide analogs using standard Hammett a values
Rapid Reduction Of Nitrate Ion In Rain Water, David M. Chittenden Ii
Rapid Reduction Of Nitrate Ion In Rain Water, David M. Chittenden Ii
Journal of the Arkansas Academy of Science
No abstract provided.
Hammett Correlations In The 1H Nmr Spectra Of Some N-Arlydihalonicotinamides, Frank L. Setliff, Nikhil G. Soman, Jody Z. Caldwell, Debra L. Rogers
Hammett Correlations In The 1H Nmr Spectra Of Some N-Arlydihalonicotinamides, Frank L. Setliff, Nikhil G. Soman, Jody Z. Caldwell, Debra L. Rogers
Journal of the Arkansas Academy of Science
Excellent linear correlations of amide proton chemical shifts (Snh) (in DMSO-d6 ) with Hammett substituent constants (5) for a series of 4-substituted anilides of four dihalonicotinic acid systems were observed. Dihalonicotinanilides with chlorine in the pyridine 2 - position exhibited a more positive slope in a Hammett plot of S^H vs - aR- where R is the substituent in the 4 position of the benzene ring. This observation is explained in terms of the inductive effect of chlorine which results in a slightly more acidic amide proton, which in turn causes an enhanced hydrogen bonding tendency to solvent. Four disubstituted …
Model For The Co Poisoning Of Hydrodesulfurization Catalysts. Synthesis And Structure Of {Ru(Co)[Pph2sc12h7)]2cl2}.2ch2br2, Mark Draganjac, Thomas B. Rauchfuss, Arnold L. Rheingold
Model For The Co Poisoning Of Hydrodesulfurization Catalysts. Synthesis And Structure Of {Ru(Co)[Pph2sc12h7)]2cl2}.2ch2br2, Mark Draganjac, Thomas B. Rauchfuss, Arnold L. Rheingold
Journal of the Arkansas Academy of Science
The treatment of {Ru[(PPh2SC12H7)]2Cl2} with CO at ambient conditions results, after work up, in the isolation of the monocarbonylated species {Ru(CO)[(PPh2SC12H7)]2Cl2}, I. Crystals of I(C51H38Br4Cl20P2RuS2; F.W. = 1284.6) are triclinic; Ppa= 11.587(3), b = 13.010(4), c = 17.309(4) A, a = 93.32(2)°, p = 106.51(2)°, y = 91.29(2)°; Z= 2; V=2495(1) A';d^,. = 1.709 gem 1 X(MoKa) = 0.71073 A, = 37.7 cm 1 ;R =0.0748; Rw = 0.0714 for 4141 unique reflections. The geometry about the Ru(II) center is pseudooctahedral, with the phosphine ligands in the trans configuration. The Ru-S bond distance is 2.425(3) A.
4-Substituted Anilides Of 2,6- And 5,6- Dichlorolicotinic Acid. Potential Agricultural Agents, Frank L. Setliff, Nikhil G. Soman
4-Substituted Anilides Of 2,6- And 5,6- Dichlorolicotinic Acid. Potential Agricultural Agents, Frank L. Setliff, Nikhil G. Soman
Journal of the Arkansas Academy of Science
A series of 4-substituted anilides of 2,6- and 5,6 dichloronicotinic acid were prepared. The acids were first converted to their acid chlorides, which were in turn treated with the appropriate 4-substituted aniline in chloroform. A total of 16 anilides was thus prepared, and their structures confirmed. These compounds were prepared for testing as possible herbicidal, pesticidal or fungicidal agents
Scf-Mo And Monte Carlo Calculations Of Poly (Dimethylsiloxane), Shannon H. Brownfield, Jerry A. Darsey
Scf-Mo And Monte Carlo Calculations Of Poly (Dimethylsiloxane), Shannon H. Brownfield, Jerry A. Darsey
Journal of the Arkansas Academy of Science
Self-consistent-field molecular orbital calculations are being used more and more extensively in determining the energies and properties of various confirmations of polymers. We are using the semi-quantum mechanical procedure MNDO (moderate neglect of differential overlap) to obtain various rotational conformations states of poly(dimethylsiloxane) (PDMS). Before calculation of these states, the molecule is geometrically optimized by using the ab initio procedure Guassian 86 at the 3-21G basis set level. Generations of 144 rotational states by rotating about two bonds simultaneously in increments of 30° were created. A potential energy surface was created from which Monte Carlo generated several polymer characteristics including …
Preparation Of A Series Of N-Phenylamides Of 5-Bromo-6-Chloronicontinic Acid And 5-Bromo-2-Chloronicontinic Acid, Frank L. Setliff, Jody Z. Caldwell
Preparation Of A Series Of N-Phenylamides Of 5-Bromo-6-Chloronicontinic Acid And 5-Bromo-2-Chloronicontinic Acid, Frank L. Setliff, Jody Z. Caldwell
Journal of the Arkansas Academy of Science
A series of N-phenylamides of 5-bromo 6-chloronicotinic acid and 5-bromo-2-chloronicotinic acid were synthesized by treatment of their freshly prepared acid chlorides with the appropriately ring substituted anilines. Thirty new compounds were prepared, and their structures were ascertained by elemental analyses and spectroscopic techniques. Spectroscopic trends in the infrared spectra of the two series were examined in an attempt to correlate structural and electronic effects to hydrogen bonding tendencies.
Preparation Of A Series Of Substituted N-Phenyl-5-Bromo-6-Chloro- And 5-Bromo-6-Chloronicotinates Of Potential Agricultural Interest, Frank L. Setliff, Maximillia M. Muguluma, Jody Z. Caldwell
Preparation Of A Series Of Substituted N-Phenyl-5-Bromo-6-Chloro- And 5-Bromo-6-Chloronicotinates Of Potential Agricultural Interest, Frank L. Setliff, Maximillia M. Muguluma, Jody Z. Caldwell
Journal of the Arkansas Academy of Science
Substituted phenyl esters of 5-bromo-2-chloronicotinic acid and 5 bromo 6-chloronicotinic acid were prepared. The acids were first converted to their respective acid chlorides using thionyl chloride, and the acid chlorides were immediately transformed to the esters by treatment with the appropriately substituted phenol in sodium hydroxide solution. Aunique chloride displacement of bromide was observed on attempting to convert 5,6-dibromonicotinic acid to its acid chloride
Comparison Of The Molecular Structures Of Monovalent Cation Salets Of N,N-Dimethyldithiocarbamate. Novel Synthesis And Crystal Structure Of (Phi4)(S2cn(Ch3)2)2h2o, Mark Draganjac, David Minick, Elizabeth M. Holt
Comparison Of The Molecular Structures Of Monovalent Cation Salets Of N,N-Dimethyldithiocarbamate. Novel Synthesis And Crystal Structure Of (Phi4)(S2cn(Ch3)2)2h2o, Mark Draganjac, David Minick, Elizabeth M. Holt
Journal of the Arkansas Academy of Science
Crystals of the tetraphenylphosphonium N,N-dimethyldithiocarbamate dihydrate (C₂₇H₃₀NO₂PS₂; F.W. = 495.6) are monoclinic; P2₁/n; a = 13.349(6), b = 20,968(6), c = 9.800(4) Å, β = 109.01(3)°; Z = 4; V = 2593.4(16) Å^3; Dₓ = 1.269 gcm- 3 . Data were collected at ambient temperature using MoKα radiation (λ = 0.71069 Å).F(000) = 1048, linear absorption coefficient, n = 2.80 cm- 1. The structure was solved by direct methods and subsequently refined by full matrix least squares techniques. Final R value = 0.064 for 1 61 0 reflections and 298 varied parameters. Due to the nature of the cation, interactions …
Preparation Of A Series Of Pyridyl Phenylureas Of Potential Agricultural Interest, Frank L. Setliff, Steve H. Rankin, Mark W. Milstead
Preparation Of A Series Of Pyridyl Phenylureas Of Potential Agricultural Interest, Frank L. Setliff, Steve H. Rankin, Mark W. Milstead
Journal of the Arkansas Academy of Science
Substituted phenylurea derivatives of 3-amino-2-chloro-5-methylpyridine and 5-amino-2-chloro-3- methylpyridine were prepared by treating the amines with appropriately substituted phenyl isocyanates. Structure- confirming spectral data are also presented.
Improved Synthesis Of 5-Methylbenz(A)Anthracene, Jia Che, Dominic T.C. Yang
Improved Synthesis Of 5-Methylbenz(A)Anthracene, Jia Che, Dominic T.C. Yang
Journal of the Arkansas Academy of Science
A revised synthesis of 5-methylbenz(a)anthracene is reported. It involves only three simple and convenient steps starting from a commercially available compound, and gives a 82% overall yield. Bromination of 5-methylbenz(a)anthracene with N-bromosuccinimide (NBS) in carbon tetrachloride furnishes 5-bromomethylbenz(a)anthracene in a 92% yield. When bromination is carried out using dimethylformamide as the solvent, 7-bromo-5-methylbenz(a)anthracene is formed as the exclusive product.
Evaluation Of Sugar Cane Bagasse And Rice Straw As Process Substrates For The Production Of Ethyl Alcohol, Douglas B. Rivers, Gisella M. Zanin, George H. Emert
Evaluation Of Sugar Cane Bagasse And Rice Straw As Process Substrates For The Production Of Ethyl Alcohol, Douglas B. Rivers, Gisella M. Zanin, George H. Emert
Journal of the Arkansas Academy of Science
No abstract provided.
Preparation Of O-Fluorobenzoic Acid. An Elementary Organic Laboratory Experiment, Frank L. Setliff
Preparation Of O-Fluorobenzoic Acid. An Elementary Organic Laboratory Experiment, Frank L. Setliff
Journal of the Arkansas Academy of Science
An experiment designed for organic chemistry students at the sophomore level is presented. The experiment, which involves no special equipment and which employs only inexpensive reagents, demonstrates the conversion of anthranilic acid to o-fluorobenzoic acid via the modified Schiemann Reaction.
Apparatus For Dielectric Constant Measurements And Measurements For Water-Methanol Mixtures, James O. Wear
Apparatus For Dielectric Constant Measurements And Measurements For Water-Methanol Mixtures, James O. Wear
Journal of the Arkansas Academy of Science
A system for measuring dielectric constants has been constructed using a Sargent Oscillometer and an air bath for temperature control. The design and construction of the air bath as well as the temperature control achieved with it are described. The overall performance of the system including a computer program for forming the calculations is described. The system is one that requires calibration using two or more standard solvents and is good for both conducting and non-conducting liquids. Data are presented for water-methanol mixtures at 25 degrees with several points near pure methanol and also near pure water
On The Preparation And Properties Of Some 1,1-Dipheneyl-Syn,Trans-Truxane Derivatives, Frank L. Setliff
On The Preparation And Properties Of Some 1,1-Dipheneyl-Syn,Trans-Truxane Derivatives, Frank L. Setliff
Journal of the Arkansas Academy of Science
No abstract provided.
Heterocyclic Aromatic Fluorides By A Modified Schiemann Method (1), Frank L. Setliff
Heterocyclic Aromatic Fluorides By A Modified Schiemann Method (1), Frank L. Setliff
Journal of the Arkansas Academy of Science
No abstract provided.
Phase Equilibrium In The 1-Butene-Water System And Correlation Of Hydrocarbon-Water Solubility Data, T. W. Leland
Phase Equilibrium In The 1-Butene-Water System And Correlation Of Hydrocarbon-Water Solubility Data, T. W. Leland
Journal of the Arkansas Academy of Science
No abstract provided.
Some Optical Properties Of Vapor-Deposited Films Of Arsenic, Antimony, And Bismuth, Zaboj V. Harvalik
Some Optical Properties Of Vapor-Deposited Films Of Arsenic, Antimony, And Bismuth, Zaboj V. Harvalik
Journal of the Arkansas Academy of Science
No abstract provided.
Possibility Of Weak Alpha Branching In Radium D, B. R. Miccoli, R. R. Edwards, B. L. Robinson, R. W. Fink
Possibility Of Weak Alpha Branching In Radium D, B. R. Miccoli, R. R. Edwards, B. L. Robinson, R. W. Fink
Journal of the Arkansas Academy of Science
No abstract provided.
Ceramic Uses Of Arkansas Nepheline Syenite, Harry J. Reynolds
Ceramic Uses Of Arkansas Nepheline Syenite, Harry J. Reynolds
Journal of the Arkansas Academy of Science
No abstract provided.
Preliminary Report Of Occurrence And Properties Of Nepheline Syenite In Pulaski County, Arkansas, Harold B. Foxhall, William E. Crockett
Preliminary Report Of Occurrence And Properties Of Nepheline Syenite In Pulaski County, Arkansas, Harold B. Foxhall, William E. Crockett
Journal of the Arkansas Academy of Science
No abstract provided.
Note On The Occurrence Of D-Manitol In Native Persimmon, Irving T. Beach
Note On The Occurrence Of D-Manitol In Native Persimmon, Irving T. Beach
Journal of the Arkansas Academy of Science
No abstract provided.
Calycanthne. Distillation With Zinc Dust, Irving T. Beach
Calycanthne. Distillation With Zinc Dust, Irving T. Beach
Journal of the Arkansas Academy of Science
No abstract provided.
Vapor Pressures. I. Para-Dichlorobenzene; Glycol Diacetate., L. B. Roberts, James D. Wolfe, James Hawthorne
Vapor Pressures. I. Para-Dichlorobenzene; Glycol Diacetate., L. B. Roberts, James D. Wolfe, James Hawthorne
Journal of the Arkansas Academy of Science
No abstract provided.
Crystals Of An Insoluble Carbonate Of Copper Grown Under A Soda Solution, L. B. Roberts, Edwin Roberts
Crystals Of An Insoluble Carbonate Of Copper Grown Under A Soda Solution, L. B. Roberts, Edwin Roberts
Journal of the Arkansas Academy of Science
No abstract provided.