Showing papers on "Benzaldehyde published in 1973"
82 citations
TL;DR: The PCILO method accounts correctly for the preferred conformation of glyoxal, butadiene, benzaldehyde, benzoic acid, biphenyl and 2,2′-difluorobiphenyl as discussed by the authors.
79 citations
TL;DR: In this paper, infrared and laser Raman spectra indicate that the adsorption of benzaldehyde on alumina results in the formation of two adsorbed species, having a benzoate and a benzyl alcoholate structure, respectively.
68 citations
39 citations
TL;DR: The physical and chemical properties of the yellow crystalline products suggest that organotitanium(IV) derivatives are formed by an intramolecular "redox" process.
37 citations
TL;DR: In this article, it was shown that photo-induced cyclisation of 2-isoxazoline can lead to the formation of a mixture of syn/anti-p-tolyl trans-styryl ketoximes (syn/anti, trans-30) and anti, cis-30, 2-(p-Tolyl)-quinoline (29), the 4-hydroxymethylated derivative 32 of the latter (in small amounts), besides the β-amino-chalcone 20, benzaldehyde, p-tolualdehyde and p
Abstract: Irradiation of 3,5-diphenyl- or 3-(p-tolyl)-5-phenyl-2-isoxazoline (12 and 13, respectively) in benzene with a high-pressure mercury lamp yields 4,5-diphenyl- or 4-(p-tolyl)-5-phenyl-3-oxazoline (17 and 19, respectively) and the β-amino-chalcones 18 or 20 in addition to benzaldehyde, benzonitrile and p-tolunitrile, respectively (scheme 6 and ‘Anmerkg.’ p. 2600). The 3-oxazolines 17 and 19 are formed by route a (scheme 8) via 3-phenyl- or 3-(p-tolyl)-2H-azirine (23, R = H and CH3, respectively) and their photochemically rearranged successors, the nitrile methylides 24, as intermediates. The discovery of this reaction has served as a basis for the quickly developing photochemistry of 3-aryl-2H-azirines [2] [24].
Photolysis of the 2-isoxazoline 13 in methanol leads to the formation of a mixture of syn/anti-p-tolyl trans-styryl ketoximes (syn/anti, trans-30) and anti, cis-30, 2-(p-tolyl)-quinoline (29), the 4-hydroxymethylated derivative 32 of the latter (in small amounts), besides the β-aminochalcone 20, benzaldehyde, p-tolualdehyde and p-tolunitrile (scheme 9). It could be shown that the stereoisomeric ketoximes 30 are photochemically interconvertible (scheme 12) and that at least one mechanism of formation of 2-(p-tolyl)-quinoline (29) is the photo-induced cyclisation of p-tolyl-cis-styryl ketoximes (cis-30) (scheme 13). A tentative mechanism for the formation of p-tolual-dehyde is given in scheme 10; the crucial step is the protonation of p-tolunitrile methylide (24, R = CH3) by methanol at the nitrile carbon atom, after which hydrolysis yields the aldehyde.
37 citations
TL;DR: In this paper, the configurations of 6-methoxyaurone and its photoisomer were assigned on the basis of chemical and NMR evidence, based on which they were described as a condensation of coumaran-3-one and benzaldehyde.
35 citations
TL;DR: The chloroform extract of the heartwood of Pterocarpus santalinus yielded a mixture of red pigments which could be separated by polyamide column chromatography into two major compounds, Santalin-A and B, which gave the same permethyl ether, C38H36O10 which had 8 methoxyls and formed a number of derivatives typical of anhydrobenzopyranols as mentioned in this paper.
35 citations
TL;DR: In this article, the reaction of 2-phenyl-1,3-dioxolans with n-butyl-lithium gives olefins in a highly Stereospecific fragmentation reaction.
Abstract: In certain cases the reaction of 2-phenyl-1,3-dioxolans with n-butyl-lithium gives olefins in a highly Stereospecific fragmentation reaction In particular, the reaction constitutes the crucial step in a convenient preparation of trans-cyclo-octene from cis-cyclo-octeneA mechanism is proposed involving initial metallation of the dioxolan followed by concerted cycloelimination to olefin and benzoate ion Support for this mechanism, in three instances, is provided by the isolation of products derived by in situ trapping of the lithium derivative of the dioxolan by benzoate ion
19 citations
TL;DR: The photolysis of benzaldehyde and its ring-deuterated analogue has been studied in various solvents by the combined techniques of flash photo-lysis with time-resolved e.r.s. detection and chemically induced dynamic nuclear polarisation (CIDNP) as mentioned in this paper.
Abstract: The photolysis of benzaldehyde and its ring-deuterated analogue has been studied in various solvents by the combined techniques of flash photolysis with time-resolved e.s.r. detection and chemically induced dynamic nuclear polarisation (CIDNP). In efficient hydrogen donors triplet benzaldehyde abstracts hydrogen to give the ketyl radical, which decays with first order kinetics. In n-hexane abstraction occurs from benzaldehyde itself to give both the ketyl and benzoyl radicals; benzoyl disappears by a pseudo first-order reaction with the solvent (k= 1.6 × 103 s–1). Using naphthalene as quencher shows that all the benzoyl originated in the triplet reaction, and that the rate of the triplet abstraction reaction is diffusion controlled (k= 1.64 × 109 l. mol–1 s–1). In inert fluorocarbon solvents (PP2 and PP9) and in the undiluted liquid a third radical is produced whose identity is uncertain. In PP2 benzoyl disappears by dimerisation (k= 1.0 × 109 l. mol–1 s–1) and the third radical by slow first-order reaction (k= 85 ± 20 s–1). The ketyl spectrum was too weak for its decay kinetics to be determined in both PP2 and n-hexane. CIDNP experiments showed that the same primary radical pair was produced in a variety of solvents and were used to elucidate the radical reaction pathways; in only the strong hydrogen donor propan-2-ol did the primary pair include a solvent radical.
19 citations
TL;DR: In this paper, 1-(2-Carboxyphenyl)-3,3-dimethyltriazene, on being heated in benzaldehyde, affords 2dimethylaminobenzhydrol and cis-and trans-2,4-diphenyl-1, 3-benzodioxins; similar products were obtained with some other carbonyl compounds.
Abstract: 1-(2-Carboxyphenyl)-3,3-dimethyltriazene, on being heated in benzaldehyde, affords 2-dimethylaminobenzhydrol and cis- and trans-2,4-diphenyl-1,3-benzodioxins; similar products were obtained with some other carbonyl compounds.
TL;DR: For the reaction between benzaldehyde and phosphonoesters or nitriles, the formation of oxyanionsRS,RS is much more reversible starting from phosphonizers than from nitrides.
TL;DR: In this paper, the authors studied the kinetics of the oxidation of benzyl alcohol to benzaldehyde by acid permanganate in the presence of fluoride ions and suggested a mechanism involving transfer of a hydride ion from the alcohol carbon to the oxidant.
Abstract: The kinetics of the oxidation of benzyl alcohol to benzaldehyde by acid permanganate in the presence of fluoride ions have been studied. The reaction constant ρ for the oxidation of benzyl alcohol and nine substituted benzyl alcohols has a value of –1·76 ± 0·05 at 30 °C. The activation enthalpies and entropies for the ten compounds are linearly related. The oxidation of αα-dideuteriobenzyl alcohol indicated a kinetic isotope effect; kH/kD= 2·70 at 30 °C. The reaction does not show any solvent isotope effect. A mechanism involving transfer of a hydride ion from the alcohol carbon to the oxidant is suggested.
TL;DR: A substituted allyl organoborane, disiamyl(3-phenyl-2-butenyl)borane has been prepared in situ by the monohydroboration of 3phenyl 1, 2-butadiene with disiamymylborane as mentioned in this paper, which reacts readily with butyraldehyde, benzaldehyde, acrolein and acetone.
TL;DR: In this paper, the photochemical reaction of α-nitroepoxides showed marked solvent dependence, and the effects of acidity and hydrogen-donating property of solvents on the excited α-nodes were interpreted in terms of effects of the acidity.
Abstract: The photochemical reaction of α-nitroepoxides showed marked solvent dependence. The photolysis of (1,2-epoxy-2-nitropropyl)benzene (I) in 2-propanol led to the formation of three products 1-phenyl-1-isopropoxy-2-propanone (IIb), 1-phenyl-1,2-propanedione oxime (III) and 1-hydroxy-1-phenyl-2-propanone oxime (IV), whereas on irradiation in ether I gave exclusively IV. However, in t-butyl alcohol, benzene, acetone, acetonitrile or n-hexane, I was not susceptible to photolysis. The photolysis of α,α′-epoxy-α-nitrobibenzyl (V) in ether gave benzoin oxime (VII) in addition to benzaldehyde and benzoic acid, whereas in methanol it gave benzoin methyl ether (VI) in the dark. These reactions are interpreted in terms of effects of the acidity and hydrogen-donating property of solvents on the excited α-nitroepoxides. The pyrolysis of I and V were also examined.
TL;DR: Furfuraldehyde, 4-hydroxybenzaldehyde, and 4hydroxy-3-methoxybenzalde- hyde were converted into 2-furylacetic, 4hydroxyphenylacetic and 4- hydroxy-3meth-oxyphencyclacetic acids respectively on reaction with glyoxal bisulphite and cyanide in alkaline solution as mentioned in this paper.
Abstract: Furfuraldehyde, 4-hydroxybenzaldehyde, and 4-hydroxy-3-methoxybenzalde- hyde were converted into 2-furylacetic, 4-hydroxyphenylacetic and 4- hydroxy-3-meth-oxyphenylacetic acids respectively on reaction with glyoxal bisulphite and cyanide in alkaline solution. Under the same reaction conditions, 2-hydroxybenzaldehyde yielded 2- hydroxyphenylacetic acid and 3-(2?-hydroxypheny1)-2H-chromen-2-one. When ammonia was present in the reaction mixture, furfuraldehyde and 4- hydroxy-benzaldehyde formed 2-furylacetamide and 4- hydroxyphenylacetamide respectively. Alternatively, in the presence of methylamine, furfuraldehyde yielded 5-(2?-furyl)-2-imino-1-methyl-2,5- dihydropyrrole-3,4-diol and benzaldehyde gave the corresponding phenyldihydropyrrolediol.
TL;DR: In this article, the X-ray structural analysis of the dibromo derivative of the 4-p-bromobenzylidene was examined on the basis of the DIBromo derivatives of the dimer.
TL;DR: In this paper, the same activation with cupric chloride and zinc chloride was successfully applied to the reaction of aromatic compounds with benzaldehyde diethylthioacetal and to the acylation of 1,2-bis(acylthio)ethanes.
Abstract: Benzylation of aromatic compounds, such as anisole, m-xylene, toluene, and benzene, with various benzyl sulfides in the presence of equimolar amounts of cupric chloride and zinc chloride was investigated. For example, in the case of benzylation of anisole with 4-benzylthiopyridine, o- and p-benzylanisoles were obtained in 79% yield in the presence of cupric chloride and zinc chloride. On the other hand, when the reaction was carried out in the presence of cupric chloride alone, the yield of benzylanisoles was low. The similar activation with cupric chloride and zinc chloride was successfully applied to the reaction of aromatic compounds with benzaldehyde diethylthioacetal and to the acylation of aromatic compounds with 1,2-bis(acylthio)ethanes.
TL;DR: In this article, it was shown that methyl heptafluoro-n-propyl trans-styryl sulphone with neutral permanganate or basic hydrolysis of trichloromethyl heptifluoro n-propane-1-sulphonic acid as its potassium salt has good yield.
Abstract: Oxidation of various methyl polyfluoroalkyl sulphides and of ethyl trifluoromethyl sulphide gives either the corresponding sulphoxides or the sulphones depending on the oxidising agent or the conditions used. Carbanion formation with both the sulphoxides and the sulphones has been demonstrated by deuterium exchange and by reaction with sodium hypochlorite, and with methyl heptafluoro-n-propyl sulphone by reaction with benzaldehyde and with iodine in the presence of base to give heptafluoro-n-propyl trans-styryl sulphone and tri-iodomethyl heptafluoro-n-propyl sulphone, respectively, in high yield. Oxidation of methyl heptafluoro-n-propyl sulphone with neutral permanganate or basic hydrolysis of trichloromethyl heptafluoro-n-propyl sulphone gives heptafluoro-n-propane-1-sulphonic acid as its potassium salt in good yield.
Patent•
27 Jun 1973TL;DR: In this paper, the formulae are defined as follows: 1.3-AMINO-2,4,6-TRICHLORO-BENZALDEHYDE-SULFONYLHYDRAZONES OF THE FORMULA, in which R is an optionally halogen-substituted alkyl radical of 1-4 carbon atoms, or an aryl radical which is optionally substituted by one or more alkal or haloalkyl radicals of 1 -4 atoms, halogen or NO2 radicals
Abstract: 3-AMINO-2,4,6-TRICHLORO-BENZALDEHYDE-SULFONYLHYDRAZONES OF THE FORMULA in which R is an optionally halogen-substituted alkyl radical of 1-4 carbon atoms, or an aryl radical which is optionally substituted by one or more alkyl or haloalkyl radicals of 1-4 carbon atoms, halogen or NO2 radicals, WHICH POSSESS ANTI-LEPORINE, ANTI-RODENT AND INSECTICIDAL PROPERTIES.
TL;DR: In this paper, a new group of photocrosslinkable polyesters formed by the Knoevenagel reaction is described, which permits preparation of photoesensitive polymers, where physical properties can be potentially varied through choice of the polyol and the dicarboxylic acid.
Abstract: A new group of photocrosslinkable polyesters formed by the Knoevenagel reaction is described. The approach permits preparation of photoesensitive polymers, where physical properties can be potentially varied through choice of the polyol and the dicarboxylic acid. The following compounds were prepared and studied: (1) products from a Knoevenagel reaction of poly(trimethylopropane azelate cyanoacetate) with benzaldehyde, furaldehyde, and 2-ethylbutyraldehyde and (2) products from a Knoevenagel reaction of poly(1,3-propyl malonate) with benzaldehyde, p-methoxybenzaldehyde, and 2-ethylbutyraldehyde. Conventional unsaturated polyesters such as poly(1,3-propyl fumarate) and poly(1,3-propyl maleate) were prepared and used for comparison.
TL;DR: Bistrifluoromethyl nitroxide abstracts aldehydic hydrogen atoms from acetaldehyde, propionaldehyde, pivalaldehyde, benzaldehyde, m- and p-tolualdehyde and pentafluorobenzaldehyde with great ease, to give NN-bistrifyhylhydroxylamine and the corresponding (bistrinifluorsomethylamino-oxy)carbonyl-alkane or -arene in almost quantitative yields as discussed by the authors.
Abstract: Bistrifluoromethyl nitroxide abstracts aldehydic hydrogen atoms from acetaldehyde, propionaldehyde, pivalaldehyde, benzaldehyde, m- and p-tolualdehyde, terephthalaldehyde, and pentafluorobenzaldehyde with great ease, to give NN-bistrifluoromethylhydroxylamine and the corresponding (bistrifluoromethylamino-oxy)carbonyl-alkane or -arene in almost quantitative yields. Basic hydrolysis of the carbonyl compounds ArCO2·N(CF3)2(Ar = Ph or C6F5) yields the corresponding arenecarboxylic acids, and attack of bistrifluoromethyl nitroxide on the phenyl compound at elevated temperature leads to nuclear substitution with the formation of (bistrifluoromethylamino-oxy)[(bistrifluoromethylamino-oxy)carbonyl]benzenes.
TL;DR: In this article, the reaction of benzyl phenylmethanethiosulfinate with morpholine was found to give dibenzyl trisulfide together with dib enzyl disulfide, benzaldehyde and N-thiobenzoyl-morpholine and the reaction mechanism was discussed.
Abstract: The reaction of benzyl phenylmethanethiosulfinate with morpholine was found to give dibenzyl trisulfide together with dibenzyl disulfide, benzaldehyde and N-thiobenzoyl-morpholine and the reaction mechanism was discussed. In the reaction with other secondary amines instead of morpholine, dibenzyl trisulfide was also obtained.
TL;DR: In this article, a four-centre transition state is proposed and it is suggested that hydride transfer from boron to the carbonyl carbon atom may be energetically important in forming the activated complex.
Abstract: Rates of reduction of substituted acetophenones and benzaldehydes by morpholine–borane in aqueous ethanol are enhanced by the introduction of electron-withdrawing groups in the carbonyl compound are are relatively independent of the water : ethanol ratio. Reduction by morpholine–[2H3]borane, is somewhat slower (kH/kD= 1·23 and 1·47 for acetophenone and benzaldehyde respectively) and a pronounced retardation of rate is observed for reduction by morpholine–cyanoborane. A four-centre transition state is proposed and it is suggested that hydride transfer from boron to the carbonyl carbon atom may be energetically important in forming the activated complex. No significant intramolecular catalysis occurs on substitution of a hydroxy-group ortho to the carbonyl carbon atom.
TL;DR: In this article, the acidity dependences of the electronic spectra of benzaldehyde and acetophenone were examined in concentrated acid media, and it was shown that the conjugate acids of these cations can fluoresce even in water.
Abstract: Aldehydes and ketones derived from benzene are generally thought to phosphoresce but not to fluoresce (1). Although fluorescence has been observed from aldehydes and ketones derived from medium and large polycyclic aromatic hydrocarbons in hydroxylic solvents (2), benzaldehyde and aceto-phenone do not fluoresce even in water. However, in concentrated acid media we have observed intense fluorescence from the conjugate acids of benzaldehyde and acetophenone, an observation which has potential analytical significance. Moreover, in concentrated sulfuric acid media, we have observed phosphorescence from the cations derived from benzaldehyde and acetophenone enabling calculation of the dissociation constants of these cations in the lowest triplet state. These observations prompted the examination of the acidity dependences of the electronic spectra of benzaldehyde and acetophenone.
TL;DR: The enthalpies of transfer from methanol to dimethylformamide for a wide variety of aromatic compounds are additive properties of the groups present within the molecules as discussed by the authors.
Abstract: The enthalpies of transfer from methanol to dimethylformamide for a wide variety of aromatic compounds are additive properties of the groups present within the molecules. Values of ΔΔHs fail to be ...
TL;DR: In this article, the reactions of propanal and benzaldehyde on various alumina oxides were investigated under different conditions, and the resulting products were identified by synthesized compounds and TLC and GLC.
Abstract: Die Umsetzungen von Propanal und Benzaldehyd an verschiedenen Aluminiumoxiden wurden bei unterschiedlichen Bedingungen untersucht. Die dabei entstandenen Stoffe wurden durch Vergleichssubstanzen mit Hilfe der DC und GC nachgewiesen.
Reactions on Alumina Oxides
The reactions of propanal and benzaldehyde on various alumina oxides were investigated under different conditions. The resulting products were identified by synthesized compounds and TLC and GLC.