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Showing papers on "Substituent published in 1969"


Patent
14 Apr 1969
TL;DR: In this paper, high molecular weight Mannich condensation products of alkyl-substituted hydroxyaromatic compounds are used to add additive agents to lubricant oil.
Abstract: High molecular weight Mannich condensation products of (1) high molecular weight alkyl-substituted hydroxyaromatic compounds whose alkyl substituent has upward from 40 to 20,000 carbon atoms, (2) an amine which contains an AND (3) AN ALDEHYDE IN THE RESPECTIVE REACTANT MOLAR RATIO OF 1: 0.1-10:1.0-10 CONDENSED WITH A BORON COMPOUND ARE NOVEL DISPERSANT-DETERGENT LUBRICANT OIL ADDITION AGENTS. Solutions of those addition agents in lubricant oil are novel and unique compositions affording anti-sludge and varnish deposition and corrosion inhibition.

237 citations



Journal ArticleDOI
TL;DR: In this article, the authors measured the chemical shifts of each of the carbons of simple aliphatic carboxylic acids and their corresponding anions from formic to valeric acid in aqueous solution.
Abstract: The ^(13)C chemical shifts of each of the carbons of the simple aliphatic carboxylic acids and their corresponding anions from formic to valeric acid have been measured in aqueous solution. Perhaps surprisingly, ionization of an aliphatic acid results in a downfield shift of its carbon resonances. The results have been correlated with other substituent effects, with ^(13)C and H resonances in corresponding hydrocarbons, and with the distance between the carboxylic(ate) group and the carbons undergoing resonance absorption.

133 citations


Journal ArticleDOI
TL;DR: The relations between the chemical structure of non-electrolytes and their ability to permeate cell membranes are analysed at the level of molecular forces, using the measurements of reflexion coefficients in gall-bladder epithelial cells tabulated in the preceding paper.
Abstract: The relations between the chemical structure of non-electrolytes and their ability to permeate cell membranes are analysed at the level of molecular forces, using the measurements of reflexion coefficients in gall-bladder epithelial cells tabulated in the preceding paper. Stronger solute: water forces and weaker solute: membrane forces are associated with lower permeating power. The portions of the membrane controlling non-electrolyte permeation behave as nearly pure hydrocarbons with very few hydrogen-bonding sites. Most substituents (hydroxyl, ether, carbonyl, ester, amino, amide, urea, nitrile) are shown to decrease permeation in proportion to the number and strength of intermolecular hydrogen bonds which they form with water, while intramolecular hydrogen bonding accelerates permeation. Carbon-carbon double bonds and triple bonds and aromatic residues decrease permeability due to hydrogen bonds involving $\pi $ electrons. Inductive effects, in which a substituent indirectly modifies permeability by withdrawing or releasing electrons at an adjacent hydrogen bonding site, are most noticeable for halogens, the nitro group, double and triple bonds, and branched alkyl groups. Altered forces between membrane hydrocarbons and the solute retard the permeation (weaker forces) of fluorine compounds and branched compounds, and slightly accelerate the permeation (stronger forces) of other halogen derivatives and compounds with long carbon chains. The main factor in the increase of permeability with increasing hydrocarbon chain length is an entropy effect associated with a change in local water structure; and this effect is partly responsible for the decrease in permeability with chain branching, whose origin is particularly complex.

128 citations


Journal ArticleDOI
TL;DR: In this paper, the N-H stretching bands in carbon tetrachloride were studied and it was found that there are two types of intramolecular hydrogen bonds in these molecules, which result in two different cyclized conformations, C5 and C7, containing respectively, five and seven atoms in the ring.
Abstract: Some experimental data are given on the infrared spectra between 3300 and 3500 cm−1 of dilute solutions in carbon tetrachloride of three types of model compounds: CH3−CONH-CH(R1)-CONH(R2), (I); CH3-CON(CH3)-CH(R1)-CONH(R2), (II) and CH3-CONH-CH(R1)-CON(R2)2, (III). In studying the N-H stretching bands, it was found that there are two types of intramolecular hydrogen bonds in these molecules; these result in two different cyclized conformations, C5 and C7, which contain respectively, five and seven atoms in the ring. By using model substances I, II, and III, in which the nitrogen atoms are unequally substituted, it is possible to identify the N-H stretching bands which are to be ascribed to the N-H oscillators included in the two different chelated conformations. It is found also that the stretching frequency of a free N-H oscillator depends upon the substituent on the nitrogen atom. Thus, it is possible to observe, with some of the model compounds I, four different absorption bands located at 3340, 3420, 3440, and 3460 cm−1. The first two are ascribed to the N-H oscillators included in the Hbonds which lock the C7 and C5 conformations; the last two correspond to free N-H which differ with the substituent on the nitrogen atom.

120 citations


Patent
14 Apr 1969
TL;DR: In this article, the authors present a comparison of different types of conformations of high-and low-weighted ALKYL-SUBSTITUTed PHENOL and ALDEHYDEHDE.
Abstract: PRODUCTS OF THE CONDENSATION OF (1) A HIGH MOLECULAR WEIGHT ALKYL - SUBSTITUTED HYDROXYAROMATIC COMPOUND WHOSE ALKYL SUBSTITUENT HAS UPWARD FROM 40 TO 20,000 AND ATOMS, (2) A LOWER MOLECULAR WEIGHT ALKYL-SUBSTITUTED PHENOL WHOSE ALKYL-SUBSTITUENT HAS 2 TO 20 CARBON ATOM, (3) AN AMINE HAVING TWO PRIMARY AMINO (-NH2) GROUPS AND (4) AND ALDEHYDE IN THE RESPECTIVE MOLAR RATIO OF REACTANTS OF 2.0:0.7-1.4-2.0:2.8-4.0, ARE NOVEL ASHLESS-TYPE (METAL FREE) MINERAL-OIL SOLUBLE ADDITON AGENTS HAVING DISPERSANT DETERGENT AND ANTI-OXIDANT FUNCTIONSAFFORDING ANTI-SLUGE AND ANTI-VARNISH DEPOXITION AND CORROSION INHIBITION IN CRANKCASE LUBRICATING COMPOSITIONS SUBJECTED TO LOW OR HIGH TEMPERATURE IN-SERVICE USE. SUCH CONDENSATION PRODUCTS ARE PREPARED EITHER BY SINGLE STEP REACTION CONDUCTED BY SUBJECTING ALL FOUR OF THE REACTANTS IN THE STATED MOLAR RATIO OF REACTANTS TO A SINGLE CONDENSATION REACTION UNDER KNOWN MANNICH CONDENSATION REACTION CONDITIONS OR BY A TWO STEP REEACTION WHEREIN REACTANTS (1), (3) AND (4) ARE FIRST SUBJECTED TO MANNICH CONDENSATION CONDITIONS IN THE RESPECTIVE MOLAR RATIO OF 2:1.4-2.0:1.4-2.0 AND THE ESULTING FIRST STEP PRODUCT IS FURTHER CONDENSED WITH REACTANTS (2) AND (4) USED IN THE ESPECTIVE MOLAR RATIO OF 0.7-1.0:1.4-2.0.

100 citations




Patent
29 Dec 1969
TL;DR: In this paper, a 2.5DIMMERCACTO-1,3,4THIADIAZOLES were used for thwarting COPPER CORROSION by active SULFUR.
Abstract: NOVEL AND USEFUL 2-HYDROCARBYLDITHIO-5-MERCAPTO-1,3,4THIADIAZOLES ARE PREPARED BY OXIDATION COUPLING OF EQUAL MOLECULAR PORTIONS OF A HYDROCARBYL MERCAPTAN AND 2,5DIMERCAPTO-1,3,4-THIADIAZOLE OR ITS ALKALI METAL MERCAPTIDE. 2-HYDROCARBYLDITHIO - 5 - MERCAPTO-1,3,4-THRIADIAZOLES ARE UNUSUAL SCAVENGERS OF ELEMENTAL SULFUR, FOR EXAMPLE ONE MOLE CAN DEACTIVATE 100 ATOMS OF ELEMENTAL SULFUR AT A TEMPERATURE OF ABOUT 210*F. AND 25 ATOMS OF ELEMENTAL SULFUR AT ABOUT 300*F. THE SULFUR DEACTIVATION MAKES 2-HYDROCARBYLDITHIO-5-MERCAPTO-1,3,4-THIADIAZOLES USEFUL FOR PREVENTING COPPER CORROSION BY ACTIVE SULFUR. ILLUSTRATIVE OF 2-HYDROCARBYLDITHIO-5-MERCAPTO-1,3,4-THIADIAZOLES ARE THOSE HAVING AS THE HYDROCARBYL SUBSTITUENT ALKYL, CYCLOALKYL, ALKARYL AND ARALKYL GROUPS.

80 citations


Journal ArticleDOI
TL;DR: In this article, the barriers to rotation about the amide CN bond in eighteen substituted N,N-dimethylbenzamides have been determined by complete line shape analysis of the NMR spectra of the n,Ndimethyl protons.
Abstract: The barriers to rotation about the CN bond in eighteen substituted N,N-dimethylbenzamides have been determined by complete line shape analysis of the NMR spectra of the N,N-dimethyl protons. The barriers have been correlated with the substituent constants σ and σ+. It has been shown that polar solvents increase the barrier in N,N-dimethylbenzamide. Acid catalysis of rotation about the amide CN bond in N-(p-N,N-dimethylcarboxamidobenzyl)-pyridinium bromide has been investigated. 18O exchange studies show that catalysis is due to N-protonation rather than the formation of a tetrahedral intermediate. The rate of rotation is a function of the Hammett acidity function, H0, and the water activity, and it is shown that proton exchange between the N- and O-protonated species involves the intermediacy of a water molecule. The differences in chemical shifts for the non-equivalent N, N-dimethyl groups of the benzamides are also a function of the substituents. Possible explanations of this phenomenon are discussed.

77 citations


Journal ArticleDOI
TL;DR: In this article, the lower molecular weight carboxylic acids, formic, acetic, propionic, n-butyric, isobutric and trimethylacetic have been studied to find whether there is any trend in thermodynamic properties due to mass or structure of the alkyl substituent.

Journal ArticleDOI
TL;DR: In this paper, the 3La(π,π*) state was shown to have a singlet character due to the heavy-atom effect, which accounts for the observation that the phosphorescence spectrum involves out-of-plane-polarized vibrational bands.
Abstract: Phosphorescence and absorption spectra, phosphorescence- and excitation-polarization, spectra and phosphorescence lifetimes were measured at 77°K for benzaldehyde, acetophenone and their eight derivatives with a halogen atom, or a hydroxyl, methoxyl or amino group as a substituent at the para position. In chloro- and bromo-derivatives, the phosphorescent triplet state is of the (n,π*) type, and is mixed with the 1La(π,π*) state by direct spin-orbit interaction, as in the case of the parent carbonyls. In addition, owing to the heavy-atom effect, it gains its singlet character by the mechanism (Remark: Graphics omitted.) which accounts for the observation that the phosphorescence spectrum involves out-of-plane-polarized vibrational bands. Substitution of a more electron-donating hydroxyl, methoxyl, or amino group brings about a change of the phosphorescent state from the 3(n,π*) state to the; 3La(π,π*). The following mechanisms are shown to be important to the 3La(π,π*) state: (Remark: Graphics omitted.) Th...

Journal ArticleDOI
01 Jul 1969-Talanta
TL;DR: The influence of the substituent on the nitrogen atom with respect to the rate and pattern of decomposition of N,N-disubstituted dithiocarbamie acids has been studied and a mechanism to accommodate the observed results has been proposed.

Journal ArticleDOI
TL;DR: In this paper, the quasi-equilibrium theory of mass spectra has been used to determine the intensity ratio [A]+/[M]+, where [A]- is a fragment ion and [M] is a molecular ion.
Abstract: Based on the quasi-equilibrium theory of mass spectra it is shown that the intensity ratio [A]+/[M]+, where [A]+ is a fragment ion and [M]+ is the molecular ion, is given by [A]+/[M]+ = f′ (k1/kt) ((1/f) − 1), where f is the fraction of molecular ions with insufficient energy to fragment, f′ is the fraction of [A]+ ions with insufficient energy to fragment, and k1/kt is the fraction of fragmenting molecular ions which form [A]+. For substituted acetophenones it is shown that f depends on the substituent present and that f′ k1/kt is also substituent dependent for formation of both [CH3CO]+ and [YC6H4CO]+. It is also shown that no direct information concerning the effect of a substituent on the rate of a particular fragmentation reaction can be obtained from intensity studies. The ionization potentials of the parent molecules and the appearance potentials of the [YC6H4CO]+ fragment ions have been measured for fifteen substituted acetophenones and the correlations with substituent constants are discussed.




Journal ArticleDOI
TL;DR: The polarographic reduction of the arene-ironcyclopentadienyl compounds (arene = benzene, naphthalene, fluorene, diphenyl, phenanthrene) was investigated on the dropping mercury electrode as mentioned in this paper.

Journal ArticleDOI
TL;DR: In this paper, a series of aminocarbenepentacarbonylchromium complexes of the type (CO)5CrC(Me)NR1R2 is reported.
Abstract: The preparation of a series of aminocarbenepentacarbonylchromium complexes of the type (CO)5CrC(Me)NR1R2 is reported. The influence of steric and of substituent effects upon the physical properties of the complexes has been investigated. Attention is drawn to elimination reactions which may occur during the preparation of aminocarbene complexes with secondary amines.

Patent
Jacques Martel1
11 Jul 1969
TL;DR: In this paper, the process for the preparation of cyclopropane carboxylic acid of the formula "STR1" was described, in which the CO 2 H substituent on the carbon 1 and CO 2 N substituents on carbon 2 are in the cis-position relative to one another, and Z represents the R 2 residue which has the same meaning as R 1 but is identical or different thereto.
Abstract: Process for the preparation of racemic or optically-active cyclopropane carboxylic acid of the formula ##STR1## wherein the CO 2 H substituent on the carbon 1 and the ##STR2## substituent on the carbon 2 are in the cis-position relative to one another, R 1 represents a hydrogen, an alkyl radical, an aralkyl radical, an aryl radical, an alkenyl radical, an alkynyl radical, a cycloalkyl radical, a cycloalkenyl radical, a heterocyclic radical, these radicals being able to be substituted, specifically by lower alkyl or lower alkoxy, or represents a cyano group, an acyl group, a formyl group, an alkoxycarbonyl group or a nitro group, and Z represents the R 2 residue which has the same meaning as R 1 but is identical or different thereto, or the R 3 residue, which represents an allyl radical, a benzyl radical, a cyano group, an acyl group, a formyl group, an alkoxycarbonyl group, or a nitro group, or R 1 and Z together form a saturated or unsaturated carbon homocycle or heterocycle, whose ring can support substituents such as lower alkyls or lower alkoxys, or functions such as ketonic functions, or together form a polycyclic aromatic residue such as a fluorene residue.

Journal ArticleDOI
TL;DR: The 17O spectra of some ortho and para-substituted acetophenones were determined in this paper to examine the effect of substituent polarity and steric hindrance on the acetyl oxygen shieldings.
Abstract: The 17O spectra of some ortho- and para-substituted acetophenones were determined to examine the effect of substituent polarity and steric hindrance on the acetyl oxygen shieldings. The results are...

Journal ArticleDOI
TL;DR: In this article, the main properties of partially methylated methyl glucosides were derived from the fragmentation scheme of permethylated pyranoses by a consideration of the effects of the different substituents.

Journal ArticleDOI
TL;DR: In this paper, it was shown that hydrogen bond formation between the amido hydrogen and the hypochlorite oxygen atom is the primary reaction with the three molecular chlorinating agents.
Abstract: Various secondary amides have been N-chlorinated, at high and at low pH. The reactivity of the chlorinating reagents with all the amides investigated was found to have the sequenceThe substituent groups R1 and R2 of the amide were found to have large effects on the rate of chlorination. With the three molecular chlorinating agents, the reactivity of the amides was found to be in the orderWith hypochlorite ion the reverse order of reactivity was observed. These results are discussed and reaction mechanisms proposed. It is proposed that, when a hypochlorite ion is a chlorinating agent, the primary reaction is hydrogen bond formation between the amido hydrogen and the hypochlorite oxygen atom, but that the donation of electrons from the amido N to the Cl atom is the primary reaction with the molecular chlorinating agents.


Journal ArticleDOI
TL;DR: In this paper, the mass spectra of a group of m- and p-substituted acetanilides were measured to determine the effect of the substituents, if any, on the rate of C2H2O expulsion (rearrangement) vs. the speed of [CH3CO]+ formation (simple cleavage).
Abstract: The mass spectra of a group of m- and p-substituted acetanilides were measured to determine the effect of the substituents, if any, on the rate of C2H2O expulsion (rearrangement) vs. the rate of [CH3CO]+ formation (simple cleavage). Our results agree with observations of others in that substituents which raise the ionization potential of the aromatic ring appear to localize, on the average, less charge density on this locus, and conversely. The atomic composition of the substituent, however, irrespective of its position, seems to determine the relative rates of the competing reaction. Although in several cases Zm/Zp values were close to unity, rearrangement of isomeric molecular ions to a common species is shown not to occur.

Journal ArticleDOI
TL;DR: The electrochemical reduction of 6-substituted purines has been examined over the available pH range by direct and alternating current polarography, and the effects of substitution evaluated in respect to significant electrochemical characteristics as discussed by the authors.
Abstract: The electrochemical reduction of 6‐substituted purines has been examined over the available pH range by direct‐ and alternating‐current polarography, and the effects of substitution evaluated in respect to significant electrochemical characteristics. Where the bonds are available in the pyrimidine moiety, a four‐electron polarographic wave due to hydrogenation of these bonds is observed; purine itself and 6‐methylpurine give two twoelectron waves. The energy‐controlling step involves reduction of the protonated bond. The current is essentially diffusion controlled at low pH where the wave is relatively constant in height and kinetically controlled at higher pH where it begins to disappear. Correlation of the ease of reduction, as measured by , with total polar substituent constant and polar substituent constant (σ*) indicates either an absence of mesomeric and steric effects due to the substituents or their transmittal by an inductive mechanism and, further, that none of the substituents exerts any specific effect different from those exerted by the other substituents. Substitution in the 6‐position influences mostly the bond order and the electronic charge distributions on N(1) and N(3), which, in turn, largely determine the reducibility; correlates linearly with the quantum mechanically calculated magnitudes of these quantities, but not with other bond orders and charges. also correlates linearly with electron‐acceptor properties as represented by the calculated energy of the lowest empty molecular orbital ( coefficients) and with for proton acquisition (the protonation, which occurs prior to electron transfer, seems to have no significant role in the potential‐determining step except in the region where the wave has nearly disappeared). Isoguanine generally deviates from the various correlations. Adsorption involving an uncharged site in the molecule is markedly greater with derivatives having bulky substituents.

Journal ArticleDOI
TL;DR: The mass spectra of twenty-six commercially available medicinal phenothiazines have been determined at high resolution as discussed by the authors, and the side chain attached to the 10 position of the phenothia ring contains nitrogen and fission of the CC bond α to this nitrogen gives in most cases the base peak.
Abstract: The mass spectra of twenty-six commercially available medicinal phenothiazines have been determined at high resolution. In each compound, the side chain attached to the 10-position of the phenothiazine ring contains nitrogen and fission of the CC bond α to this nitrogen gives in most cases the base peak. Some of the compounds are also substituted at the 2-position and this substituent generally remains intact, though some substituents such as acetyl, propionyl, methoxyl and methylthio can undergo fragmentation. Fragmentations fall into three groups; those which give ions representing a part of the side chain; those which give ions representing the intact phenothiazine ring with part of the side chain attached; those which give ions representing a partially fragmented ring system.


Journal ArticleDOI
TL;DR: In this paper, the NMR and UV spectra of α,N-diphenylnitrone and its derivatives were measured and the effect of the electron-donating power of the para substituent was investigated.
Abstract: The NMR and UV spectra of α,N-diphenylnitrone and its derivatives which have a substituent at the para position of the α-phenyl group and some of which have in addition a methyl substituent at the ortho position of the α-phenyl group were measured. Examination led to the following conclusions. The NMR signal of the ortho protons of the α-phenyl group appears at a very low field. This is mainly attributed to the direct effect of the negatively charged oxygen atom of the nitrone group. Increase in the electron-donating power of the para substituent enhances this effect.

Journal ArticleDOI
TL;DR: In this article, the presence or absence of intramolecular H-bonds, determined by IR spectroscopy, was useful in assigning configurations for some of the compounds.