Benzylidene Aniline Research Articles

Theoretical approach of the conformations of benzylidene aniline using the PCILO method

The conformational properties of benzylidene aniline (BA) were investigated using the PCILO method. Evidence has been provided that the optimization of geometry plays a prominent part, in agreement with recent experimental work on photoelectron spectroscopy by Haselbach.

Zur Reaktivität von C=N-Doppelbindungssystemen, IX1 Reaktionen mit Harnstoff, Thioharnstoff, N.N-Dimethylsemicarbazid bzw. Cyanamid.

Benzylidene aniline reacts with Ac2O/AcOH yielding 2-phenylperhydro-s-triazin-4,6-dione (“benzalbiuret”). Thiourea or N,N-dimethylsemicarbazide give the corresponding 8-triazines in a similar way. However, the reaction with cyanamide leads to N-benzylidene carbamic acid nitriles.

Vibrational spectroscopy of liquid crystals: 2. Normal coordinate analysis of benzaniline: basis structure for some liquid crystals

The vibrational spectrum of benzalaniline, some derivatives of which have been found to exhibit crystalline properties in the liquid phase, has been interpreted in the light of new experimental data and from an accurate normal coordinate calculation. Kinematic and dynamic couplings are of great importance even for the modes corresponding to the central group. A modified Urey-Bradley force field refined on three isotopic species of benzene has been determined. In the course of studies on the vibrational spectra of nematogenic Schiff bases, it has been found that the complete vibrational assignment of the parent molecule, benzaniline or benzylidene-aniline (B.A.) has never been reported. In a previous report [1], one of us (G.V.) showed the similarity in the Raman spectra of B.A. and (methoxy)-benzylidene-(butyl)-aniline (M.B.B.A.) which is a nematic type liquid crystal. For structural studies of the nematic phase itself and for the use of liquid crystals as solvents in vibrational spectroscopie studies of solute molecules, one needs to know the full assignment. The purpose of the present paper is to discuss the interpretation of the vibrational spectrum of B.A. in the light of new experimental data and from an accurate normal coordinate calculation.

Electro-optical Kerr-effect in solutions of benzylidene aniline and its derivatives

The Kerr-effect for three molecules which have a structural relationship to the nematogen MBBA (N-p-methoxybenzylidene-p-n-butyl aniline) has been studied in solution in carbon tetrachloride. It was found that whereas benzylidine aniline (BA) and p-methoxy benzylidene aniline (MBA) were unassociated in the range of concentration and temperature studied here, benzylidene-p-n-butyl anline (BBA) exhibited the anomalous behaviour found previously for MBBA in its isotropic state and in solution, being a characteristic of association of the molecules. The results for BBA and MBBA are discussed in relation to evidence for association in MBBA obtained by Gierke and Flygare from light scattering studies and in terms of available relations between light scattering and Kerr-constant factors and orientational correlation functions between molecules.

Zur Reaktivität von C =N-Doppelbindungssystemen, III Eine einfache Olefinierungs-Reaktion / The Reactivity of the C=N-Double Bond System, III A Simple Olefination Reaction

The reaction of benzylidene anilines with compounds having an activated CH,- or CH,-group in the presence of aliphatic or cyclic anhydrides (acetic anhydride, propionic anhydride or succinic anhydride) gives olefines in good yield.

Zur Reaktivität von C=N-Doppelbindungssystemen, I / The Reactivity of the C=N Double Bond System, I

The adduct from benzylidene aniline and acetic anhydride gives 1,4-diphenyl-azetidin-2-one if heated at 210°C in diphenylmethane or diphenylsilane.

Addition des ylures de carbonyle derives de gem-dicyanoepoxydes sur les benzylidene anilines substituees

The reaction of substituted benzylidene anilines with 1,1-dicyano or 1-cyano 1-ethoxycarbonyl epoxides gives oxazolidines, the structures of which is established by NMR spectroscopy. The formation of oxazolidines proceeds via regiospecific addition of epoxide derived ylid to imine. The influence of ylid substituants and imine substituants on the reaction may be interpreted by interactions of the frontier orbitals.

Investigations of the cis‐trans‐Isomerization of Benzylidene Aniline II. Kinetic Parameters of the cis‐trans‐Isomerization in Different Solvents [1

AbstractThe thermal cis‐trans‐isomerization of benzylidene aniline was investigated in the aprotic solvents cyclohexane (ϵ = 2), and acetonitrile (ϵ= 37) and the protic solvents ethanol (ϵ = 25) and methanol (ϵ= 36), and also in 98% H2SO4.Whereas the isomerization in the organic solvents proceeds via an inversion mechanism this reaction is drastically hindered or even blocked in 98% H2SO4.It is shown that the experimental activation energy for the cis‐trans‐inversion is composed of three parts: 1. rehybridization energy E*rehyb, 2. difference between the dipole field energies of the cis‐isomer and the kinetic transition state due to different dipole moments of these species and 3. difference in the hydrogen bond solvation energies of the cis isomer and the kinetic transition state. It can be shown that the second dielectric term vanishes in solvents with high dielectric constants. By comparison of the activation energies of the cis‐trans isomerization in cyclohexane and acetonitrile we obtain μsp < μcis. By comparison of the activation energies as measured in acetonitrile and methanol the hydrogen bond solvation energy of the cis‐isomer in methanol is estimated to be approximately ‐ 2 kcal/mol. Additionally the cis‐trans‐isomerization of 10 substituted benzylidene anilines was investigated in cyclohexane.The frequency factors for the reaction rates of the substituted benzylidene anilines are all within the narrow range from 4 · 1012 to 4 · 1013 sec‐1, whereas the activation energies vary from 14.6 to 18.8 kcal. The kinetic results agree qualitatively with those, obtained by Wettermark in ethanol. The equilibrium constant K and reaction enthalpy δ H° for the reaction trans‐benzylidene aniline ⇌ cis‐benzylidene aniline is estimated for the solvent chlorobenzene by combining appropriate kinetic data:magnified image.

PMR spectra of benzylidene aniline and its hydroxy derivatives

PMR spectra of benzylidene aniline and its hydroxy derivatives

Complexing and fission of benzylidene anilines with Pd(II), Pt(II) and Rh(III) chlorides

Complexing and fission of benzylidene anilines with Pd(II), Pt(II) and Rh(III) chlorides

Desactivation de polystyrene anionique “vivant” au moyen de bases de schiff: Preparation de polystyrene α,ϖ-arylamine

It is shown that deactivation of anionic “living” polystyrene by Schiff bases, such as benzylidene aniline, leads to polymers with secondary aromatic amine end-groups. The reactivity of the C  N double bond towards polystyrene anions allows a quantitative reaction only in a polar solvent. If the Schiff base contains also an ester group as another electrophilic deactivator for anionic polystyrene, it is shown that the reactivity of the C  N double bond is greater than that of the ester group. Polymer molecules having aromatic secondary amine end-groups react much more slowly than polymer molecules having aromatic primary amine end-groups with acid chlorides.

Hydrolysis of benzylidene aniline in the presence of cetyl trimethylammonium bromide

Hydrolysis of benzylidene aniline in the presence of cetyl trimethylammonium bromide

The influence of amphiphilic compounds on ionic organic reactions in aqueous solution

The effects of a cationic amphiphilic compound on the rates of a proton- and an hydroxyl ion-catalysed reaction have been investigated. Even at very low concentrations, such a compound retards the proton-catalysed hydrolysis of benzylidene aniline, and this effect increases with increasing concentration of the cationic compound. Conversely, the hydroxyl ion-catalysed hydrolysis of benzylidene acetophenone is accelerated at low concentrations of cationic compound; however, at higher cationic concentrations, the reaction is retarded. These effects are qualitatively explained by considering the effect of a cationic compound on the electrostatic forces between the reactant ions and on the steric shielding of the reaction site.

Hydrolysis of benzylidene aniline in the presence of cetyl trimethyl ammoniumbromide

Hydrolysis of benzylidene aniline in the presence of cetyl trimethyl ammoniumbromide

The Relationship Between Estrogenic Action and Chemical Constitution in a Group of Azomethine Derivatives

The relation between chemical constitution and estrogenic action has been investigated in a group of azomethine derivatives comprising all 4,4′ substitution combinations of four groups—H, CH3, CH3O, OH. 4,4′-Dihydroxy benzylidene aniline produced an estrogenic response in 12.5mg. doses subcutaneously and 25 γ doses intravaginally. Absorption spectra were determined for all derivatives.

The action of guanidine bicarbonate on the acid sodium sulfite addition products of benzylidene anilines

The action of guanidine bicarbonate on the acid sodium sulfite addition products of benzylidene anilines

Societies and Academies

LONDON. Chemical Society, May 28.—Prof. Meldola, F.R.S., vice-president, in the chair.—Taxine, the alkaloid of yew, by Dr. Thorpe, C.B., F.R.S., and Mr. G. Stubbs. The authors have confirmed the observations of Hilger and Brande, Marmé and others on the occurrence of an amorphous alkaloid in yew.—The sampling of soils, by Dr. J. W. Leather. Comparative experiments were made in India to determine the possible accuracy of the auger method of sampling soils, the available phosphoric acid and potash being taken as a standard of comparison. The results showed that in most cases the agreement was good between the samples, but that there was occasionally a divergence of about five per cent.—Some excessively saline Indian well waters, by Dr. J. W. Leather. An examination of some well waters collected in the Muttra district, United Provinces, India, showed that they contained from .2 to 2 per cent, of saline substances consisting of sulphate, nitrate, chloride and carbonate of sodium.—Nitrobromo-derivatives of fluorescein, by Dr. Hewitt and Mr. Woodforde. Several of these substances have been isolated and characterised.—Phosphorus sesquisulphide and its behaviour with Mitscherlich's test, by Mr. F. G. Clayton. Analyses of commercial specimens of this substance have been made, and show that they contain from 83 to 97 per cent, of sesquisulphide.—Atomic and molecular heats of fusion, by Mr. P. W. Robertson. The author finds that for a number of the elements and their binary inorganic derivatives a relation between (atomic or molecular) heat of fusion, absolute melting point and atomic volume exists which is capable of a more or less general representation by an equation of the form —The preparation of mixed ketones by heating mixed calcium salts of organic acids, by Mr. E. B. Ludlam. An extension of the method proposed by Young in 1891.—Isomeric additive products of methyl, ethyl and propyl benzyl ketones with benzylidene aniline, part iv., by Dr. Francis and Mr. Ludlam.—The influence of solvents on the rotation of optically active compounds, part iii., influence of benzene, toluene, o-xylene, m-xylene, p-xylene and mesitylene on the rotation of ethyl tartrate, by Dr. T. S. Patterson. The above solvents exert in the order named an increasing influence in diminishing the rotation of ethyl tartrate; in the case of the first four solvents this effect reaches a minimum and a maximum at appropriate concentrations.—iv. Influence of naphthalene on the rotation of ethyl tartrate, by Dr. T. S. Patterson. The effect of this hydrocarbon is to increase the observed rotation.