Results 371 to 380 of about 57,413 (403)

Rhenium-catalyzed C-H aminocarbonylation of azobenzenes with isocyanates.

Organic and biomolecular chemistry, 2015
The first C-H aminocarbonylation of azobenzenes with isocyanates is achieved by using rhenium-catalysis, which provides an expedient and atom-economical access to varied o-azobenzamides from readily available starting materials.
Xiao Geng, Cong-Hui Wang
semanticscholar   +1 more source

A cascade synthesis of aminohydantoins using in situ-generated N-substituted isocyanates.

Chemistry, 2015
Nitrogen-substituted isocyanates are rarely utilized but powerful building blocks for the development of cascade reactions in heterocyclic synthesis.
Jean-François Vincent-Rocan, Christian Clavette, Kyle Leckett, André M. Beauchemin   +3 more
semanticscholar   +1 more source

Occupational asthma due to isocyanates

European Respiratory Journal, 1988
162 subjects who had been exposed to isocyanates, who had developed symptoms during the exposure period, or in the evening or night and, therefore, had a history compatible with isocyanate-induced asthma, were studied with inhalation challenge testing to isocyanates (toluene diisocyanate and methylene diphenyl diisocyanate) and methacholine, because ...
MAPP, Cristina, BOSCHETTO, Piera, DAL VECCHIO L, MAESTRELLI P, FABBRI LM   +4 more
openaire   +5 more sources

The Reactions of Isocyanates and Isocyanate Derivatives at Elevated Temperatures

Rubber Chemistry and Technology, 1959
Abstract Qualitative and quantitative studies with model compounds have shown that a variety of reactions may occur at 100–300° in molecules containing isocyanate, urea and urethane groups. All or most of these reactions are subject to catalysis so that they may be induced to proceed at lower temperatures.
openaire   +2 more sources

[(Salcen)Cr(III) + Lewis base]-catalyzed synthesis of N-aryl-substituted oxazolidinones from epoxides and aryl isocyanates.

Chemical Communications, 2014
[(Salcen)Cr(III) + Lewis base] was found to be a highly active and selective catalyst system in the [2+3] cycloaddition between epoxides and isocyanates to form 5-oxazolidinones.
R. Paddock, D. Adhikari, Richard L. Lord, M. Baik, S. Nguyen   +4 more
semanticscholar   +1 more source

Direct detection of ultralow trace amounts of isocyanates in air using a fluorescent conjugated polymer.

Chemical Communications, 2014
A fluorescence sensory polymer containing the pentiptycene and tetraphenylethylene units linked by acetylene was synthesized for direct detection of isocyanates in air. Eight industrially available aliphatic and aromatic isocyanates were tested.
Khama Rani Ghosh, S. Saha, J. Gao, Z. Wang   +3 more
semanticscholar   +1 more source

The polycyclotrimerization of isocyanates

Polymer Science U.S.S.R., 1981
Abstract A simultaneous polycyclotrimerization (PCTM) of aromatic with aliphatic components has been shown to be feasible with the catalytic system of triethylene diamine and phenylglycidyl ether. In bulk PCTM of diisocyanates, the functional groups conversion was quantitative.
S.V. Vinogradova, L.F. Larina, Ts. M. Frenkel, V. A. Pankratov, L. I. Komarova, V.V. Korshak   +5 more
openaire   +2 more sources

Synthesis of Isocyanates

1997
The interaction of carbon monoxide with organic nitro compounds is a thermodynamically highly favourable process. For reaction (1): $$PhN{O_{2\left( 1 \right)}} + 3C{O_{\left( g \right)}} \to PhNC{O_{\left( 1 \right)}} + 2C{O_{2\left( g \right)}}$$ (1) a ΔH0 = − 128.8 Kcal/mol can be calculated assuming ΔH0 f = − 16.1 KcaUmol for PhNCO(1) [1].
Fabio Ragaini, Sergio Cenini
openaire   +2 more sources

Isocyanates

EMC - Pathologie professionnelle et de l 'environnement, 2004
A. Maître, A. Perdrix
openaire   +1 more source

Injury by Isocyanates

1982
The incidence of occupational asthma is continuously increasing in many working populations: in workers engaged in polyurethane-foam production and in other plastics industries, in the wood and furniture industries, in drug production and other chemical plants, in agriculture and the food industries (for instance, among bakers), and so on.
openaire   +2 more sources