117714-41-7Relevant academic research and scientific papers
Laser photolysis of naphthoquinone diazide in cyclohexane - two-laser chemistry
Bendig,Mitzner
, p. 1004 - 1008 (1994)
The laser photochemistry of 1,2-naphthoquinone-diazide-(2)-5-sulfonic acid phenylester in cyclohexane has been investigated. The photolysis experiments have been done using a KrF laser pulse (generation pulse) and a nitrogen laser pulse (transformation pulse) with various time delay from 40 ns up to 1 s. At a time delay between the two laser pulses in the μs-region, the formation of indene and cyclohexyl-indene derivatives has been observed, additional to the corresponding indenecarboxylic acid. The laserspecific formation of these compounds is the result of the electronic excitation of the intermediately formed ketene and its reaction by decarbonylation. The time delay for getting a high yield of the indene and the cyclohexyl-indene derivatives correlates closely with the rise time and the life time of the ketene.
Flash photolytic generation and study of ketene and carboxylic acid enol intermediates formed by the photolysis of diazonaphthoquinones in aqueous solution
Andraos,Chiang,Huang,Kresge,Scaiano
, p. 10605 - 10610 (2007/10/02)
Flash photolysis of each of five diazonaphthoquinones (1-diazo-2(1H)-oxonaphthalene-4-sulfonate, 2-diazo-1 (2H)-oxonaphthalene-4-sulfonate, 2-diazo-1(2H)-oxonaphthalene-5-sulfonate, phenyl2-diazo-1(2H)-oxonaphthalen-4-sulfonate, and phenyl 2-diazo-1(2H)-oxonaphthalene-5-sulfonate) in aqueous solution was found to produce two short-lived intermediates preceding the ultimate indenecarboxylic acid reaction products. Decay of the first of these intermediates is catalyzed weakly by hydroxide ion but not by dilute perchloric acid nor by acetic acid buffers, and its uncatalyzed reaction shows only weak solvent isotope effects; this serves to identify this intermediate as the ketene formed by photo-Wolff rearrangement of the diazonaphthoquinone. Decay of the second intermediate is catalyzed by perchloric acid in dilute acid solutions, with saturation of this catalysis occurring in more concentrated acid, and it shows general acid catalysis in acetic acid buffers. The perchloric acid catalyzed reaction gives an appreciable solvent isotope effect in the normal direction (kH/kD > 1), which increases in magnitude as this catalysis becomes saturated. This serves to identify this intermediate as the indenecarboxylic acid enol formed by hydration of the first intermediate. The form of acid catalysis by perchloric acid and the change in isotope effect indicates that this enol ketonizes through its enolate ion, with a shift of initial state from enol to enolate as the acidity of the medium is decreased; analysis of the kinetic data shows the enols to be rather strong acids, with pKa = 0.4-1.3.
On the photodecomposition mechanism of o-diazonaphthoquinones
Barra, Mónica,Fisher,Cernigliaro,Sinta,Scaiano
, p. 2630 - 2634 (2007/10/02)
The mechanism for the photodecomposition of several o-diazonaphthoquinones has been examined in acetonitrile solution using time-resolved laser flash photolysis techniques. It is concluded that the Wolff rearrangement, which involves the formation of a ketene intermediate, can be regarded as a concerted process in the nanosecond time scale. It is suggested that the reaction of the ketene with water, which is well known to yield 3-indenecarboxylic acids, involves the intermediacy of a ketene hydrate. Pyridine, a molecule frequently employed as a carbene trap/probe, efficiently traps the ketene in these systems; this scavenging reaction can be employed as a probe for the study of the dynamics of ketene reactions, but in some systems it may represent a problem in carbene studies if the possibility of ketene reactions is not considered.
Synthesis and Photochemistry of 1,2-Naphtoquinonediazide-(2)-n-sulfonic Acid Derivatives
Bendig, J.,Sauer, E.,Polz, K.,Schopf, G.,Koch, A.
, p. 9207 - 9216 (2007/10/02)
The 1,2-naphthoquinonediazide-(2)-6- and -7-sulfonic acid esters (7c, 7d) have been synthesized for first time starting from the 1-naphthyl-amine-6- and -7-sulfonic acids (1c, 1d), respectively, via Bucherer reaction, nitrosation, reduction, diazotation, sulfochlorination, esterification.The synthesis of the corresponding 8-sulfonic acid ester 7e was not successful by this way.On photolysis the 1,2-naphthoquinonediazide-(2)-6- and -7-sulfonic acid phenyl esters (7c, 7d) form the corresponding (phenoxysulfonyl)-indenecarboxylic acid (10c, 10d) in the same manner like the known 5-sulfonic acid 4-sulfonic acid ester 7a a photochemically induced ester cleavage occurs additionally (λ 320 nm).
Synthesis and Characterization of Substituted 2-Diazo-1-oxo-1,2-dihydronaphthalenes and Their Products of Photolysis and Thermolysis
Baumbach, B.,Bendig, J.,Nagel, T.,Dubsky, B.
, p. 625 - 635 (2007/10/02)
Several 2-diazo-1-oxo-1,2-dihydronaphthalenes (1, 2) have been synthesized by reaction of selected hydroxy compounds and 2-diazo-1-oxo-1,2-dihydronaphthalene-5- and -4-sulfonylchloride, respectively.Photolysis as well as thermolysis of 1 and 2 leads to final products, the nature of which depends on the position of substitution.So, reactions of 5-substituted derivatives (1) yield the corresponding indene-3-carboxylic acids 3 and their esters 5, respectively.In contrast, reactions of 4-substituted derivatives (2) lead to the formation of the 1-sulfo-indene-3-carboxylic acid derivatives 4 and 6.Prepared compounds have been characterized by means of mass, ultraviolet, infrared, 1H-n.m.r. and 13C-n.m.r. spectroscopy.
