Quinone Diazide Research Articles

A New Synthetic Approach to Pyridinium N‐Phenoxide Betaine Dyes

AbstractThe reaction of 3,5‐di‐tert‐butyl‐4‐oxo‐2,5‐cyclohexadienylidene (3d) with pyridine affords 2,6‐di‐tert‐butyl‐4‐(2,4,6‐tri‐tert‐butylpyridinio)phenolate (1d) — which is not accessible by the classical route via pyrylium salts — in reasonable yield. Carbene 3d is generated by thermal decomposition of the corresponding quinone diazide 2d in cyclohexane. Betaine 1d shows the expected large solvatochromism.

Structure and Spectroscopic Properties of p‐Benzoquinone Diazides

AbstractA series of p‐benzoquinone diazides were investigated by 13C‐NMR and IR spectroscopy as well as by semiempirical and abinitio calculations. In addition, X‐ray structure analyses of the parent compound and three derivatives were performed. The electronic structure and effects of substituents can be described in terms of diazoketo and diazonium phenolate resonance structures. While alkyl groups as substituents have only a minor influence on quinone diazides, electron‐withdrawing substituents lead to a larger participation of the aromatic diazonium phenolate structure. Benzoannellation, on the other hand, leads to a decrease of the interaction between the keto and diazo functional group and to properties more reminiscent of “ordinary” ketones and diazo compounds.

Direct observation of the cyclopropene-vinylcarbene rearrangement. Matrix isolation of bicyclo[3.1.0]hexa-3,5-dien-2-ones

4-Oxocyclohera-2,5-dienylidenes 4b-g have been generated in argon matrices at 10 K by visible-light irradiation of the corresponding quinone diazides 5. Carbenes 4 have been characterized by IR and UV-vis spectroscopy and by their characteristic thermal reaction with molecular oxygen. On irradiation into the longest-wavelength absorption (420-700 nm), carbenes 4c-g rearrange to give the highly strained bicyclo[3.1.0]hexa-3,5-dien-2-ones 3c-g, while 4b is photostable under the same conditions

Stable radical pairs under the photolysis of 2,6-di- t-butyl quinone diazide in the single crystals of sterically hindered phenols: New type of double-spin probes

Intermediate radical products, which are formed when monocrystals of sterically hindered phenols containing 10 −3 M 2,6-di- t-butyl quinone diazide are photolysed, have been studied employing EPR. We have identified the formation of carbenes and several types of radical pairs. It is found that, with a rise in temperature, a red-shift is observed for the long-wave boundary involving the formation of radical pairs. The high stability of radical pairs made it possible to measure the thermal coefficients for the linear expansion of the monocrystals. Two types of asymmetric relaxation have been identified in the EPR spectra of radical pairs.

ChemInform Abstract: Liquid‐Chromatographic Investigations on the Photolysis of 2‐Diazo‐1‐oxo‐1,2‐dihydronaphthalene‐5‐sulfonic Esters of 2,6‐Bis(2‐hydroxy‐5‐cumylbenzyl)‐4‐cumylphenol.

AbstractThe photolysis of the quinone diazides (I) in the presence of EtOH is studied.

ChemInform Abstract: Thermolysis of Sterically Hindered Benzoquinone Diazides in Acetylacetone.

AbstractThe thermolysis of the quinone diazides (I) or (V) in acetylacetone (II) gives, after cleavage of N2 and addition of (II) to the resulting carbene, the phenols (III) or (VI) in quantitative yields.

Photochemistry of quinone diazides. Intramolecular oxygen transfer and carbenoid addition during photolysis of N-allylsulfonamido quinone diazides

An indole quinone diazide, 5-(N-allylsulfonamido)-4-diazo-3-methyl-4,-7-dihydroindol-7-one, which is a potential precursor of a spiro -cyclopropane-indol-7-one structure has been prepared. A study of its photolysis and that of a model compound has identified oxygen transfer from the sulfonamido substituent as a process which competes with intramolecular carbenoid addition.

Double exposure stabilization of positive photoresist

AbstractPositive photoresists appeared to be the most promising material in VLSI microfabrication for ten or more years from now. Thus, processing know‐how needs to be accumulated continuously. This work deals with thermal characteristics of positive photoresist. The following facts were declared experimentally. The quinone diazide, photosensitizer, was thermally decomposed at around 140°C to release N2. Simultaneously the surface layer of resist film was changed into innert state, called as ‘husk’, with low gas permeability and high chemical resistance. These thermal changes in resist film affect the photoresist to SiO2 adhesion. In this work a noble process, named double exposure stabilization, is developed to get sufficient chemical resistance and good adhesion simultaneously.

Quinone diazide cyclizations - a direct route to dihydrobenzofurans

The reaction of ortho-quinone diazides with electron-rich alkenes produces 2,3-dihydrobenzofurans. The ortho-quinone diazides are formed from the ortho-nitrophenols by reduction and diazotization. The reaction of an ortho-quinone diazide with 2,3-dihydrofuran produces a furo-[2,3-b]benzofuran ring system.

New, deep UV resist (LMR) for lift-off technique

A new, deep UV resist, LMR (low molecular weight resist) has been developed. LMR is a quinone–diazide ester of a novolak resin whose molecular weight is about 1000. It has strong absorption in the deep UV region (12 μm−1 at 250 nm). LMR is negative working upon irradiation with deep UV light and forms an overhung structure with a single development step. The sensitivity of LMR is 30 mJ/cm2 and 0.3 μm wide spaces are clearly resolved. By use of LMR, a simple and reliable lift-off process is realized. Submicron wide metal patterns having a thickness twice that of the resist can be formed by this process.

Direct and sensitized photolysis of 1,4-benzoquinone diazides in organic solvents

1. The quantum yields in the phototransformation of 1,4-benzoquinone diazides in organic solvents range from 0.1 to 0.5; the yields are determined by the structure of the quinone diazide and the nature of the solvent. 2. Acceleration of the phototransformation of 1,4-benzoquinone diazides is observed in the presence of a sensitizer, viz., Acridine Yellow; the coefficient of sensitization varies over a wide range (1.5–50) and depends on the nature of the solvent and the substituents in the quinone diazide molecule.

Effect of polarity of medium on thermal stability of 1,4-benzoquinone diazides

The thermolysis rate of 1,4-benzoquinone diazides in aprotic media is independent of the polarity of the solvent, as well as of the electronic and steric effects of the substituents in the quinone diazide nucleus; in protic media, due to complexing with the solvent, the thermolysis rate of the quinone diazides is determined by the steric effects of the substituents and the polarity of the medium.

Phenyl-substituted 1,4-benzoquinone diazides I. Synthesis and thermal and physicochemical stability

1. A method of synthesizing phenyl-substituted 1,4-benzoquinone diazides has been developed. 2. The equilibrium constants in the quinone diazide ⇄ diazonium salt reaction for the phenyl-substituted 1,4-benzoquinone diazides have been determined. 3. The parameters of the thermal and photochemical stability of a number of 1,4-benzoquinone diazides have been obtained.

Reaction of carbene of cyclohexadienone type with multiple bonds of conjugated dienes

1. The 1,2-addition products are formed initially when the cyclohexadienone carbene is reacted with the multiple bonds of conjugated dienes, which are isomerized under the conditions for the thermolysis of the quinone diazide, but are stable under photolysis conditions at 5–7°. 2. The rate of the thermal isomerization of the 1,2-addition products was studied.

Chemical polarization of nuclei in reaction of 2,6-di-tert-butylbenzoquinone diazide with primary amines

A mechanism for the reaction of quinone diazides with primary amines was proposed on the basis of the chemical polarization of the nuclei.

Thermal decomposition of 2,6-di-tert-butyl-p-benzoquinone diazide in ketones

1. The thermal decomposition of 2,6-di-tert-butyl-p-benzoquinone diazide in aliphatic and aromatic ketones was investigated. 2. The thermal decomposition of the quinone diazide in aliphatic ketones leads to the formation of epoxyspiran derivatives, while the thermolysis of the quinone diazide in acetophenone gives only derivatives of 2,6-di-tert-butyl-phenol. 3. The appearance of 2,6-di-tert-butyl-p-benzoquinone in the reaction mixture is the result of acid hydrolysis of the epoxyspirodienone formed under the action of phenols to 2,6-di-tert-butylhydroquinone, followed by its oxidation.

Reaction of p-benzoquinone diazides with amines

1. The reaction of p-benzoquinone diazides with secondary aliphatic amines leads to the formation of the corresponding 3,3-dialkyl-substituted triazenes. 2. The character and yield of the end reaction products are determined both by the degree of electrophilicity of the quinone diazide and the electron-donor properties of the amines, and also by the reaction conditions. 3. A mechanism was proposed for the reaction of p-benzoquinone diazides with aliphatic amines.