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A series of catalysts based on supported copper nanoparticles have been prepared and tested in the amide bond formation from tertiary amines and acid anhydrides, in the presence of tert‐butyl hydroperoxide as an oxidant. Copper nanoparticles on zeolite Y (CuNPs/ZY) was found to be the most efficient catalyst for the synthesis of amides, working in acetonitrile as solvent, under ligand‐ and base‐free conditions in air. The products were obtained in good to excellent yields and in short reaction times. The CuNPs/ZY system also exhibited higher catalytic activity than some commercially available copper and iron sources and it was reused in ten reaction cycles without any further pre‐treatment. This methodology has been successfully scaled‐up to a gram scale with no detriment to the yield.

A series of catalysts based on supported copper nanoparticles have been prepared and tested in the amide bond formation from tertiary amines and acid anhydrides, in the presence of tert‐butyl hydroperoxide as an oxidant. Copper nanoparticles on zeolite Y (CuNPs/ZY) was found to be the most efficient catalyst for the synthesis of amides, working in acetonitrile as solvent, under ligand‐ and base‐free conditions in air. The products were obtained in good to excellent yields and in short reaction times. The CuNPs/ZY system also exhibited higher catalytic activity than some commercially available copper and iron sources and it was reused in ten reaction cycles without any further pre‐treatment. This methodology has been successfully scaled‐up to a gram scale with no detriment to the yield.

I denne afhandling undersøges en ny enzymatisk proces til blegning af cellulosepulp og fjernelse af hexenuronic acid (HexA). I processen indgår en haloperoxidase (Hap) og en tertiær amin (DABCO) der testes på oxygen-delignificeret eukalyptus kraft pulp. Ved at køre processen ved konstant pH (pH 4,5; 60°C) sås en øget lyshed samt en god respons på peroxid-alkalisk ekstraktion hvor mere end 80% HexA fjernelse opnået, uden at cellulose strukturen blev nedbrudt. I et optimeret, men ikke-bufret system, blev Hap/DABCO-systemet sammenlignet med en ikke-enzymatisk HOCl behandling, og en mindre effekt af Hap/DABCO-systemet blev fundet. På samme niveau af lyshed var HOCl behandlingen overlegen i forhold til reduktion af HexA og kappanummer. Hydrogenperoxid og ikke kun den enzymatiske oxidation kan være medvirkende til blegningen under Hap/DABCO behandling. Organochlor-dannelse blev målt og vurderet at være meget højere end reference-behandlinger med chloridoxid. Det blev konkluderet, at problemet med dannelse af organochlor skal løses før en fremtidig anvendelse af Hap/DABCO teknologien., A novel approach for cellulosic pulp bleaching and hexenuronic acid (HexA) removal using a haloperoxidase (Hap) and a tertiary amine catalyst (DABCO) was tested on oxygen-delignified eucalypt kraft pulp. In a buffered system (pH 4,5, 60°C), high brightness gain, good response to peroxide-reinforced alkaline extraction and more than 80% HexA removal were achieved, while preserving cellulose integrity. In an optimized, but non-buffered system, Hap/DABCO was compared to the non-enzymatic HOCl treatment and an inferior performance of the former was found. At the same brightness level, HOCl treatment performed superior in terms of HexA and kappa number reduction. Hydrogen peroxide was proposed as most likely playing a role in contributing to the brightening during Hap/DABCO treatment. Organochlorine formation was measured and found to be much higher than reference chlorine dioxide treatments. It was concluded that the problem of organochlorine formation must be solved for this technology to be used in the future.

I denne afhandling undersøges en ny enzymatisk proces til blegning af cellulosepulp og fjernelse af hexenuronic acid (HexA). I processen indgår en haloperoxidase (Hap) og en tertiær amin (DABCO) der testes på oxygen-delignificeret eukalyptus kraft pulp. Ved at køre processen ved konstant pH (pH 4,5; 60°C) sås en øget lyshed samt en god respons på peroxid-alkalisk ekstraktion hvor mere end 80% HexA fjernelse opnået, uden at cellulose strukturen blev nedbrudt. I et optimeret, men ikke-bufret system, blev Hap/DABCO-systemet sammenlignet med en ikke-enzymatisk HOCl behandling, og en mindre effekt af Hap/DABCO-systemet blev fundet. På samme niveau af lyshed var HOCl behandlingen overlegen i forhold til reduktion af HexA og kappanummer. Hydrogenperoxid og ikke kun den enzymatiske oxidation kan være medvirkende til blegningen under Hap/DABCO behandling. Organochlor-dannelse blev målt og vurderet at være meget højere end reference-behandlinger med chloridoxid. Det blev konkluderet, at problemet med dannelse af organochlor skal løses før en fremtidig anvendelse af Hap/DABCO teknologien., A novel approach for cellulosic pulp bleaching and hexenuronic acid (HexA) removal using a haloperoxidase (Hap) and a tertiary amine catalyst (DABCO) was tested on oxygen-delignified eucalypt kraft pulp. In a buffered system (pH 4,5, 60°C), high brightness gain, good response to peroxide-reinforced alkaline extraction and more than 80% HexA removal were achieved, while preserving cellulose integrity. In an optimized, but non-buffered system, Hap/DABCO was compared to the non-enzymatic HOCl treatment and an inferior performance of the former was found. At the same brightness level, HOCl treatment performed superior in terms of HexA and kappa number reduction. Hydrogen peroxide was proposed as most likely playing a role in contributing to the brightening during Hap/DABCO treatment. Organochlorine formation was measured and found to be much higher than reference chlorine dioxide treatments. It was concluded that the problem of organochlorine formation must be solved for this technology to be used in the future.

The curing reaction of a system consisting of a diglycidyl ether of bisphenol-A (n= 0) and ZnTPyP (Zinc 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphyrin) was studied by Fourier Transform infrared spectroscopy (FTIR). A semi-empirical quantum chemistry program (MOPAC) was used to corroborate the experimental data. The tertiary amine ZnTPyP not only initiates the reaction but also reacts with the resin forming pyridone. This study demonstrates that macrocycles can be used as cross-linking agents for curing epoxy resins and that when metallomacrocycles are used, metal ions can be introduced into the network structure

Photoinduced electron-transfer reaction of α-bromomethyl-substituted benzocyclic β-keto esters with tertiary amines was investigated. Debrominated β-keto esters and ring-expanded γ-keto esters were obtained as major products. On the basis of mechanistic experiments it was concluded that these products are formed via a reaction sequence of selective carbon–bromine bond cleavage and subsequent competitive hydrogen abstraction and Dowd–Beckwith ring-expansion of the resulting primary alkyl radicals. The characteristic product distribution observed for the type of amine used is rationalized on the basis of selective reaction pathways of generated radical intermediates that depend on the nature of the amine radical cations.

Functional polymers containing Lewis bases are known as promising materials for the elaboration of highly sensitive micro-sensors for acid gas detection. In this work, poly(urethane-imide)s (PUIs) with Lewis bases were synthesized in two steps only from various functional diols (N-methyldiethanolamine, N-tert-butyldiethanolamine, N-phenyldiethanolamine and 1,4-diethanolpiperazine) containing one or two tertiary amine groups with different chemical structures. The synthesis led to high yields, high molecular weights and a good control of the PUI amine content. These good film-forming polymers were then used as SO2 sensitive coatings on Love surface acoustic wave (L-SAW) micro-sensors. The physical and mechanical properties required for an optimal micro-sensor design were determined by High Resolution Brillouin Spectroscopy of PUI thin layers. Three-layer micro-sensors were developed by respecting the conditions for the L-SAW generation. The three-layer structure included Quartz ST-90 as the piezoelectric substrate, a ZnO guiding layer and a PUI sensitive layer. These micro-sensors were weakly sensitive to temperature and thus compatible with the targeted application. The experimental results for SO 2 detection showed that all the PUI coatings greatly improved the sensitivity compared to a micro-sensor without polymer coating. The basicity of the amine groups was not determining for the micro-sensor sensitivity to the SO2 acid gas and the key factor was their steric hindrance. Finally, the micro-sensor sensitivity increased with the accessibility of the amine groups in the order Piperazine-diol < tBu-DEA ≅ Ph-DEA ≪ MDEA. © 2013 Elsevier B.V. All rights reserved.

This report computes the vibrational frequencies of seven amines. Experimental data are available for four of these molecules: trimethylamine, diethylmethylamine, bis(2-chloroethyl)methylamine, and triethylamine. The ratios are determined between the experimental and the computed frequencies of these molecules. The ratios are then used to derive a set of effective correction factors for the various vibrational modes. The vibrational frequencies are computed for three other tertiary amines: tris(chloromethyl) amine, tris(2- chloroethyl)amine (HN3), and bis(2-chloroethyl) ethylamine (HN1). The computed frequencies, the corresponding intensities, and the corrected frequencies are reported here. The authors emphasize that the correction factors are valid only for 3-21G computations., Prepared in cooperation with Pennsylvania Univ., Philadelphia.

A series of polyvinyl chloride matrix coated-wire electrodes (c.w.e) based on dinonylnaphthalene sulfonic acid (DNNS) selective to various aklylammonium ions was prepared and selectivity characteristics were evaluated. Using a set of tributylammonium c.w.e., the interference by homologous series of alkylammonium ions were studied. It was found that selectivity coefficient values for alkyammonium ions at a given carbon number decrease in order primary, secondary, tertiary, quaternary. A linear increase in log selectivity coefficient with carbon number was observed in each series. Two additional sets of electrodes selective to dodecylammonium ion and to di-n-hexylammonium ion were evaluated for response to other C-12 amines. It was observed that electrodes for primary amines show little or no response to secondary and tertiary amines, while electrodes for tertiary amines respond strongly to primary amines and less strongly to secondary amines. The effect of structural modifications was evaluated in a study of N-substituted cyclohexylamines. The dependence of the magnitude of selectivity coefficient on interferent concentration was determined for both strong and weak interfering species. For strong interferences, selectivity coefficient was observed to increase to a maximum value of characteristic concentration. For weak interferents, the selectivity coefficient variation with interferent concentration was markedly less. Guides for estimating the response to an interfering species based on its structure and molecular weight were obtained from these studies.

The mechanism of the reaction of hexafluoroacetone with trimethylsilane has been reconsidered in the light of results now available on other reactions involving nucleophilic attack on hexafluoroacetone; these include the reaction of the ketone with alkyl halides in the presence of sodium and the reaction of hexafluoroacetone with tertiary amines. It is now thought probable that the initial reaction of a silane with hexafluoroacetone is a hydride abstraction, giving a fluorinated alkoxide ion. Claims that hexafluoroacetone forms complexes with compounds of group IV elements are reexamined, and it is concluded that present evidence does not support such a suggestion. (Author), Presented at the Conference of the Chemical Institute of Canada, Saskatoon (49th), Jun 66.

Bakalářská práce se zabývá vlivem katalyzátorů na reakci vzniku polyurethanu. Teoretická část obsahuje základní poznatky z oblasti polyuretanové chemie doplněné literární rešerší na téma katalýza a mechanismus reakce vzniku polyurethanu. V experimentální části byl testován vliv katalyzátorů N,N,N',N' tetramethylethylendiaminu, 2 ethylhexanoátu cínatého, 1,4 diazabicyklo[2,2,2]oktanu a dibutylcíndilaurátu na rychlost syntézy polyurethanové pryskyřice. Měření bylo založeno na měření času, za který reakční směs dosáhne maximální teploty. Byly vypočítány efektivní koncentrace použití katalyzátorů. Doplňujícím měřením byl proveden zjednodušený výpočet aktivační energie reakce pro demonstraci vlivu teploty na sledovanou reakci., The bachelor thesis deals with the influence of catalysts on polyurethane formation. The theoretical part includes basic knowledge of polyurethane chemistry complemented by a literature review contains information about catalysis and reaction mechanism of polyurethane formation. In experimental part were studied effects of catalysts N,N,N',N' tetramethylethylenediamine, Stannous octoate, 1,4-Diazabicyclo[2.2.2]octane and Dibutyltin dilaurate at the rate of synthesis of the polyurethane resin. The measurement was based on measuring the time for which the reaction mixture reaches the maximum temperature. Effective concentrations of catalysts use were calculated. By additional measurement was performed simplified calculation of the activation energy for the demonstration of the effect of temperature on the observed reaction.

Bakalářská práce se zabývá vlivem katalyzátorů na reakci vzniku polyurethanu. Teoretická část obsahuje základní poznatky z oblasti polyuretanové chemie doplněné literární rešerší na téma katalýza a mechanismus reakce vzniku polyurethanu. V experimentální části byl testován vliv katalyzátorů N,N,N',N' tetramethylethylendiaminu, 2 ethylhexanoátu cínatého, 1,4 diazabicyklo[2,2,2]oktanu a dibutylcíndilaurátu na rychlost syntézy polyurethanové pryskyřice. Měření bylo založeno na měření času, za který reakční směs dosáhne maximální teploty. Byly vypočítány efektivní koncentrace použití katalyzátorů. Doplňujícím měřením byl proveden zjednodušený výpočet aktivační energie reakce pro demonstraci vlivu teploty na sledovanou reakci., The bachelor thesis deals with the influence of catalysts on polyurethane formation. The theoretical part includes basic knowledge of polyurethane chemistry complemented by a literature review contains information about catalysis and reaction mechanism of polyurethane formation. In experimental part were studied effects of catalysts N,N,N',N' tetramethylethylenediamine, Stannous octoate, 1,4-Diazabicyclo[2.2.2]octane and Dibutyltin dilaurate at the rate of synthesis of the polyurethane resin. The measurement was based on measuring the time for which the reaction mixture reaches the maximum temperature. Effective concentrations of catalysts use were calculated. By additional measurement was performed simplified calculation of the activation energy for the demonstration of the effect of temperature on the observed reaction.

Bakalářská práce se zabývá vlivem katalyzátorů na reakci vzniku polyurethanu. Teoretická část obsahuje základní poznatky z oblasti polyuretanové chemie doplněné literární rešerší na téma katalýza a mechanismus reakce vzniku polyurethanu. V experimentální části byl testován vliv katalyzátorů N,N,N',N' tetramethylethylendiaminu, 2 ethylhexanoátu cínatého, 1,4 diazabicyklo[2,2,2]oktanu a dibutylcíndilaurátu na rychlost syntézy polyurethanové pryskyřice. Měření bylo založeno na měření času, za který reakční směs dosáhne maximální teploty. Byly vypočítány efektivní koncentrace použití katalyzátorů. Doplňujícím měřením byl proveden zjednodušený výpočet aktivační energie reakce pro demonstraci vlivu teploty na sledovanou reakci., The bachelor thesis deals with the influence of catalysts on polyurethane formation. The theoretical part includes basic knowledge of polyurethane chemistry complemented by a literature review contains information about catalysis and reaction mechanism of polyurethane formation. In experimental part were studied effects of catalysts N,N,N',N' tetramethylethylenediamine, Stannous octoate, 1,4-Diazabicyclo[2.2.2]octane and Dibutyltin dilaurate at the rate of synthesis of the polyurethane resin. The measurement was based on measuring the time for which the reaction mixture reaches the maximum temperature. Effective concentrations of catalysts use were calculated. By additional measurement was performed simplified calculation of the activation energy for the demonstration of the effect of temperature on the observed reaction.

Bakalářská práce se zabývá vlivem katalyzátorů na reakci vzniku polyurethanu. Teoretická část obsahuje základní poznatky z oblasti polyuretanové chemie doplněné literární rešerší na téma katalýza a mechanismus reakce vzniku polyurethanu. V experimentální části byl testován vliv katalyzátorů N,N,N',N' tetramethylethylendiaminu, 2 ethylhexanoátu cínatého, 1,4 diazabicyklo[2,2,2]oktanu a dibutylcíndilaurátu na rychlost syntézy polyurethanové pryskyřice. Měření bylo založeno na měření času, za který reakční směs dosáhne maximální teploty. Byly vypočítány efektivní koncentrace použití katalyzátorů. Doplňujícím měřením byl proveden zjednodušený výpočet aktivační energie reakce pro demonstraci vlivu teploty na sledovanou reakci., The bachelor thesis deals with the influence of catalysts on polyurethane formation. The theoretical part includes basic knowledge of polyurethane chemistry complemented by a literature review contains information about catalysis and reaction mechanism of polyurethane formation. In experimental part were studied effects of catalysts N,N,N',N' tetramethylethylenediamine, Stannous octoate, 1,4-Diazabicyclo[2.2.2]octane and Dibutyltin dilaurate at the rate of synthesis of the polyurethane resin. The measurement was based on measuring the time for which the reaction mixture reaches the maximum temperature. Effective concentrations of catalysts use were calculated. By additional measurement was performed simplified calculation of the activation energy for the demonstration of the effect of temperature on the observed reaction.