Showing papers on "Pyrazoline published in 1973"

Photoconductor overcoated with triarylpyrazoline charge transport layer

Abstract: Electrophotographic plates are provided having a charge generation layer and a separate charge transport layer comprising a tri-aryl pyrazoline compound having the formula: WHEREIN N IS ZERO OR ONE, AND A, A1 and A2 are each aryl radicals.

Sensitive electrophotographic plates

Abstract: VERY SENSITIVE ELECTROPHOTOGRAPHIC PLATES ARE PROVIDED HAVING A CHARGE GENERATING LAYER COMPRISING A SQUARIC ACID METHINE DYE AND A CHARGE TRANSPORT LAYER COMPRISING A TRI-ARYL PYRAZOLINE COMPOUND.

The Intramolecular Participation of Sulfide Linkage on the Reactivity of Carbenes and Diazoalkanes. II. Alkylcarbenes and Diazoalkanes Bearing Arylthio and Allylthio Groups on β-Carbon

Abstract: β-Arylthio- and β-allylthioalkylcarbenes were generated from the corresponding ketones by a modification of the Bamford-Stevens method. Chemical evidence for the formation of novel cyclic ylides, i.e., thietanonium ylides, by an intramolecular electrophilic addition of the carbene to the sulfur atom was obtained. The resulting ylides underwent various types of rearrangements to afford cyclopropyl sulfides, thiaazulenes, thietanes, and/or tetrahydrothiophenes. The mechanisms and the relative amounts of the transition energies for these rearrangements are discussed. An intramolecular cycloaddition of β-allyl- and β-crotylthioalkyldiazoalkanes is also described. The final products of the reaction were 3-thiabicyclo[4.1.0]heptanes. A thiabicyclic pyrazoline, which is presumed to be an intermediate of the cycloaddition, could be isolated in the case of the thermal decomposition of 4-allylthio-4-methylpentan-2-one tosylhydrazone.

Addition reactions of conjugated double bonds. Part V. Stereochemistry of pyrazoline ring formation from αβ-unsaturated phenylhydrazones

Abstract: The stereochemistry of cyclisation of the phenylhydrazones of some αβ-unsaturated ketones is discussed in terms of a stereoselective enamine–imine tautomerism step. Cyclisation of the phenylhydrazone of 1-acetyl-4-t-butyl-cyclohexene results in an initial axial attack of the nitrogen nucleophile on the six-membered ring.

1-(4'-methoxysulphonyl-phenyl)-3-(4"-chlorophenyl)-pyrazoline

Abstract: Novel 1-(4'-methoxysulphonyl-phenyl)-3-(4"-chlorophenyl)pyrazoline is described which has unexpectedly a very good affinity to cellulose ester fibers and optically brighten these fibers in pure white, free from undesirable greenish or greenish-blue hues even when applied in higher concentrations; compositions containing this novel compound as well as other substances, especially detergents, are also described; and a process for optically brightening cellulose ester and particularly cellulose acetate fibers is also disclosed.

Pyrazoline stereochemistry: use of nuclear magnetic resonance shift reagents with azo-compounds

Abstract: Eu(fod)3 shifts the n.m.r. spectra of cis-azo-compounds, shereas trans-azo-compounds remain almost unaffected; shifts obtained from pyrazolines have been related to their stereochemistry.

Pyrazoline disperse optical brighteners - esp. for brightening cellulose acetate in the spinning bath

Abstract: Title cpds. of formula (I) (where R is butyl esp. n-butyl) are pref. prepared by reacting p-butylsulphonylphenylhydrazine with p-chlorophenylvinyl ketone.

Reaction of l-aryl-δ2-pyrazoline salts with lithium aluminum hydride

Abstract: The corresponding pyrazolidines were obtained by reduction of 1-aryl(1-hetaryl)pyrazoline salts. The structure of the products and the reaction mechanism are discussed.