Dissertations / Theses on the topic 'Chemical building blocks'

A collection of twenty three selectively mono-protected di- and triamines, masked with the Boc, Fmoc or Ddiv protecting groups, were synthesised via continuous flow synthesis in a self-assembled meso-scale PTFE flow reactor. The continuous flow strategy offered direct access to the mono-protected compounds in good yields, especially in the case of the Fmoc carbamates which circumvented the use of another sacrificial protecting group. Two of the mono-Boc-protected carbamates were used as starting materials to generate N-alkylglycine monomers; synthesised via tandem mono-alkylation and Fmoc carbamation, linked by an in-line scavenging protocol using a silica-based trisamine scavenger resin. The final step of the monomer synthesis employed catalytic transfer hydrogenolysis using 20% Pd(OH)2/C and 1,4- cyclohexadiene. The three-step flow procedure gave access to two monomers, with one of them being a novel N-alkylglycine unit bearing a triethylene glycol bridge. The monomers were used as building blocks to assemble new oligo-N-alkylglycines (peptoids) via microwave-assisted solid phase synthesis. Three different types of peptoids were synthesised: (i) oligo-N-(6-aminohexyl)glycines (“standard” peptoids), (ii) oligo-N-{2-[2-(2-aminoethoxy)ethoxy]ethyl}glycines (“triethylene glycol” [TEG] peptoids) and (iii) hetero-oligomers of alternating “standard” and “TEG” monomers (“hybrid” peptoids). The peptoids were evaluated for their cellular permeability and cytotoxicity with HeLa, HEK-293 and CHO cells. All the peptoids were shown to be non-cytotoxic at 10 μM based on cell proliferation assays. In general, it was found that the cellular uptake of the hybrid peptoids outperformed their standard and TEG analogues. Flow cytometry and confocal microscopy results revealed that the hybrid nonamer had the highest cellular uptake efficiency of all the peptoids synthesised. At a concentration of 1 μM, it outperformed the second best molecular transporter (standard nonamer) by a factor of seven.

Phenol and cresols represent a good example of primary chemical building blocks of which 2.8 million tons are currently produced in Europe each year. Currently, these primary phenolic building blocks are produced by refining processes from fossil hydrocarbons: 5% of the world-wide production comes from coal (which contains 0.2% of phenols) through the distillation of the tar residue after the production of coke, while 95% of current world production of phenol is produced by the distillation and cracking of crude oil. In nature phenolic compounds are present in terrestrial higher plants and ferns in several different chemical structures while they are essentially absent in lower organisms and in animals. Biomass (which contain 3-8% of phenols) represents a substantial source of secondary chemical building blocks presently underexploited. These phenolic derivatives are currently used in tens thousand of tons to produce high cost products such as food additives and flavours (i.e. vanillin), fine chemicals (i.e. non-steroidal anti-inflammatory drugs such as ibuprofen or flurbiprofen) and polymers (i.e. poly p-vinylphenol, a photosensitive polymer for electronic and optoelectronic applications). European agrifood waste represents a low cost abundant raw material (250 millions tons per year) which does not subtract land use and processing resources from necessary sustainable food production. The class of phenolic compounds is essentially constituted by simple phenols, phenolic acids, hydroxycinnamic acid derivatives, flavonoids and lignans. As in the case of coke production, the removal of the phenolic contents from biomass upgrades also the residual biomass. Focusing on the phenolic component of agrifood wastes, huge processing and marketing opportunities open since phenols are used as chemical intermediates for a large number of applications, ranging from pharmaceuticals, agricultural chemicals, food ingredients etc. Following this approach we developed a biorefining process to recover the phenolic fraction of wheat bran based on enzymatic commercial biocatalysts in completely water based process, and polymeric resins with the aim of substituting secondary chemical building blocks with the same compounds naturally present in biomass. We characterized several industrial enzymatic product for their ability to hydrolize the different molecular features that are present in wheat bran cell walls structures, focusing on the hydrolysis of polysaccharidic chains and phenolics cross links. This industrial biocatalysts were tested on wheat bran and the optimized process allowed to liquefy up to the 60 % of the treated matter. The enzymatic treatment was also able to solubilise up to the 30 % of the alkali extractable ferulic acid. An extraction process of the phenolic fraction of the hydrolyzed wheat bran based on an adsorbtion/desorption process on styrene-polyvinyl benzene weak cation-exchange resin Amberlite IRA 95 was developed. The efficiency of the resin was tested on different model system containing ferulic acid and the adsorption and desorption working parameters optimized for the crude enzymatic hydrolyzed wheat bran. The extraction process developed had an overall yield of the 82% and allowed to obtain concentrated extracts containing up to 3000 ppm of ferulic acid. The crude enzymatic hydrolyzed wheat bran and the concentrated extract were finally used as substrate in a bioconversion process of ferulic acid into vanillin through resting cells fermentation. The bioconversion process had a yields in vanillin of 60-70% within 5-6 hours of fermentation. Our findings are the first step on the way to demonstrating the economical feasibility for the recovery of biophenols from agrifood wastes through a whole crop approach in a sustainable biorefining process.

Phenol and cresols represent a good example of primary chemical building blocks of which 2.8 million tons are currently produced in Europe each year. Currently, these primary phenolic building blocks are produced by refining processes from fossil hydrocarbons: 5% of the world-wide production comes from coal (which contains 0.2% of phenols) through the distillation of the tar residue after the production of coke, while 95% of current world production of phenol is produced by the distillation and cracking of crude oil. In nature phenolic compounds are present in terrestrial higher plants and ferns in several different chemical structures while they are essentially absent in lower organisms and in animals. Biomass (which contain 3-8% of phenols) represents a substantial source of secondary chemical building blocks presently underexploited. These phenolic derivatives are currently used in tens thousand of tons to produce high cost products such as food additives and flavours (i.e. vanillin), fine chemicals (i.e. non-steroidal anti-inflammatory drugs such as ibuprofen or flurbiprofen) and polymers (i.e. poly p-vinylphenol, a photosensitive polymer for electronic and optoelectronic applications). European agrifood waste represents a low cost abundant raw material (250 millions tons per year) which does not subtract land use and processing resources from necessary sustainable food production. The class of phenolic compounds is essentially constituted by simple phenols, phenolic acids, hydroxycinnamic acid derivatives, flavonoids and lignans. As in the case of coke production, the removal of the phenolic contents from biomass upgrades also the residual biomass. Focusing on the phenolic component of agrifood wastes, huge processing and marketing opportunities open since phenols are used as chemical intermediates for a large number of applications, ranging from pharmaceuticals, agricultural chemicals, food ingredients etc. Following this approach we developed a biorefining process to recover the phenolic fraction of wheat bran based on enzymatic commercial biocatalysts in completely water based process, and polymeric resins with the aim of substituting secondary chemical building blocks with the same compounds naturally present in biomass. We characterized several industrial enzymatic product for their ability to hydrolize the different molecular features that are present in wheat bran cell walls structures, focusing on the hydrolysis of polysaccharidic chains and phenolics cross links. This industrial biocatalysts were tested on wheat bran and the optimized process allowed to liquefy up to the 60 % of the treated matter. The enzymatic treatment was also able to solubilise up to the 30 % of the alkali extractable ferulic acid. An extraction process of the phenolic fraction of the hydrolyzed wheat bran based on an adsorbtion/desorption process on styrene-polyvinyl benzene weak cation-exchange resin Amberlite IRA 95 was developed. The efficiency of the resin was tested on different model system containing ferulic acid and the adsorption and desorption working parameters optimized for the crude enzymatic hydrolyzed wheat bran. The extraction process developed had an overall yield of the 82% and allowed to obtain concentrated extracts containing up to 3000 ppm of ferulic acid. The crude enzymatic hydrolyzed wheat bran and the concentrated extract were finally used as substrate in a bioconversion process of ferulic acid into vanillin through resting cells fermentation. The bioconversion process had a yields in vanillin of 60-70% within 5-6 hours of fermentation. Our findings are the first step on the way to demonstrating the economical feasibility for the recovery of biophenols from agrifood wastes through a whole crop approach in a sustainable biorefining process.

Metal oxide nanostructures characterized by multiple morphologies and structures are at the forefront of applications driven nanotechnology research. In particular, they represent a versatile solution for performance enhancement and applications in multifunctional devices and offer distinct advantages over their bulk counterparts. The current state in ZnO nanomaterials research and its impact in nanotechnology and modern engineering are discussed through the lens of con-tinuing technological advances in synthetic techniques allowing to obtain the material with predefined specific set of criteria including size, functionality, and uniqueness. Aim of this research activity is fabrication and study of the potential ap-plications as biomolecular nanoplatforms of ZnO nanostructures obtained using different synthetic techniques ranging from vapor phase deposition (Metal-Organic Chemical Vapor Deposition) to solution growth (Chemical Bath Depo-sition). Moreover, hybrid synthetic approaches are used to obtain complex hier-archical ZnO structures having dual or multiple morphologies. The non-covalent interaction of these inorganic nanosystems with organic molecules, having spe-cific chemical behavior, represents a strategy to obtain hybrid organic-inorganic nanomaterials, thus offering interesting potentiality for the design of high per-formance devices. In particular, it is demonstrated that integration of Metal-Organic Chemical Vapor Deposition and Chemical Bath Deposition strategies with Nanosphere Colloidal Lithography allows to define two-dimensional hybrid ZnO-SiO2 nanoarrays having great potential as innovative fluorescence sensing substrates with individual addressability and tuning of the biomolecular detec-tion capability. Combination of Metal-Organic Chemical Vapor Deposition with Electro-spinning leads to fabrication of core shell Zn-doped TiO2 ZnO nanofibers char-acterised by hierarchical growth of ZnO nanoneedles onto the TiO2 nanofiber surface. XRD measurements revealed that after ZnO deposition at T > 500 °C, the TiO2 nanofibers were composed of the anatase rutile mixed phases with dif-ferent fractions of rutile, modulated by the Zn dopant concentration. These com-posite nanomaterials may be intriguing to the future study of nanofiber photo-catalysts and sensors, and functional properties based on titanium dioxide.

Deux sujets indépendants ont été traités dans ce manuscrit.Dans une première partie a été étudiée la possibilité d'obtenir des synthons chiraux à partir de la pyridine. Pour cela nous avons dans un premier temps développé une méthode originale de quaternisation des sels de pyridium et d'imidazoliums grâce à une réaction de Mitsonubu. Par la suite, des 2-aminopyridines ont été substituées puis engagées dans une réaction de quaternisation-réduction conduisant à des composants saturés. Malheureusement, des composés n'ont pu conduire aux synthons linéaires envisagés.Dans une seconde partie, nous nous sommes intéressés au développement d'un nouveau type de peptidomimétique dans lequel le lien amide est remplacé par un cycle imidazolique, ceci dans la continuité de travaux menés dans notre équipe. Dans un premier temps, nous nous sommes focalisés sur la mise au point de conditions efficaces menant au mime considéré. Cette méthodologie nous a permis la synthèse de plusieurs dipeptides.

The research work presented in this PhD thesis is focused on two research topics which aim is to enhance the sustainability of the modern biorefinery. In fact, the production of an advanced biofuel such as 1-butanol is studied in the first part, while the second part deals with the valorisation of glycerol, which is a biodiesel co-product. Therefore, in the first part of the thesis 1-butanol production by means of the Guerbet reaction is studied. The catalytic synthesis of 1-butanol is more desirable than ABE fermentation because it allows to reach higher productivity, lowering the separation costs. The study is aimed to provide a deeper understanding on the effect of acid and base active sites. Therefore, pure basic alkaline earth metal oxides were synthesized and fully characterized. Afterwards, the oxide which showed the best performance was doped with H3PO4 and its catalytic behaviour was studied. Finally, its performance was compared with that one of hydroxyapatite, even with respect to its lifetime. Dihydroxyacetone, a glycerol derivative, upgrading into lactic acid is the topic of the second part of this work. Glycerol valorisation into chemicals might help to support the economic sustainability of biodiesel production. In fact, its disposal as a waste is expensive and not sustainable according to the biorefinery concept. Therefore, a continuous process aimed at directly upgrading glycerol is highly desirable. The main problem in dihydroxyacetone conversion is the need for water-resistant catalysts. A continuous process is more convenient from both an economical and a technological point of view than a batch one. In this thesis, a thorough study of metal phosphate-based catalysts reactivity in the aqueous phase and in a continuous-feed reactor is presented. The catalysts were fully characterized in order to understand the relationship between their physico-chemical characteristics and catalytic performance.

L'auto-assemblage moléculaire est désormais considéré comme l'une des approches les plus prometteuses pour la conception de matériaux à nanostructures complexes. Cependant, les récents progrès effectués ont aussi amené la nécessité d'améliorer la compréhension des mécanismes régissant la flexibilité des molécules. Il a ainsi été décidé d'étudier l'effet de la composition des briques moléculaires sur leur processus d'assemblage, et la labilité structurale des systèmes assemblés. De manière à pouvoir comparer rigoureusement les résultats expérimentaux, un seule morphologie de briques moléculaires, en forme de "bâtonnet", a été choisie et trois groupes distincts de molécules ont été sélectionnés : non-polaires, qui ne possèdent pas de dipôle important, monofonctionelles, lesquelles possèdent une terminaison polaire et une seconde non-polaire, et bifonctionelles, constituées d'un groupe polaire à chaque extrémité séparés par une chaine non-polaire Ainsi, l'influence des groupements dipolaires sur la labilité de la nanostructure finale du matériau a pu être explorée. Cette étude permet ainsi de mettre en exergue la remarquable diversité des flexibilités structurales qui peuvent être rencontrées dans les systèmes auto-assemblés. De plus, elle dévoile le potentiel des mouvements moléculaires locaux en tant qu'approche encourageante pour fonctionnaliser des structures auto-assemblées supposées inertes ou contraintes.

There is a growing interest in the synthesis of functional materials by supramolecular assembly. Special attentions are recently attracted to understand the assembly mechanism, the incorporation of desired functionalities, and the applications. This research is to study three functional assembly systems, i.e. bridged silsesquioxanes, organic hybrid materials, and polymer aggregates By incorporating functional organic moieties into ordered silica network, self-assembly of bridged silsesquioxanes ((RO)3Si-R' -Si(OR)3) proves efficient to produce advanced organic/inorganic materials. The present research introduces four functional organic components, i.e. polydiacetylene (PDA), oligothiophene, perylenediimide and porphyrin, into the silica framework, and the resultant assemblies show interesting structures and great applications as optoelectronic devices and sensors. Particularly, this thesis demonstrates the first example to synthesize responsive mesoporous PDA systems, the first example to fabricate oligomer thin films through a simple sol-gel process, the first mechanism study on the molecular assembly at multi-length scales, and the first assembly system of macroscopically helical fibers with chiral micropores, mesopores and macropores PDA systems have been known to switch their color between blue and red when exposed to temperature, inorganic ions, organic solvents, pH and salt changes or mechanical stress, which endow them with potential applications as sensor materials. This thesis reports the first example to synthesize PDA nanocomposites that switch their colors under UV irradiation at room temperature, induced by the unique configuration change of incorporated azobenzene derivatives Environment-responsive polymer aggregates have attracted increasing attentions in recent years because of their potential applications in numerous fields, e.g. drug delivery vehicles. This thesis focuses on self-assembly of homopolymer with small organic molecules (such as poly (4-vinylpyridine), or poly (allylamine), with diacetylenic acids) or two homopolymers (sulfonated poly (ether ether ketones), and PAA) in common solvents, resulting in the formation of microsized hollow spheres or nanoparticles, respectively. Both of them indicate potential applications as controlled and targeted delivery vehicles
acase@tulane.edu

Nanotechnology has emerged as one of the most exciting new and developing fields in science today. New nanoscale materials and devices such as nanoparticles, nanocomposites, nanowires, and nanosensors could revolutionize the 21st century in the same way that the transistor and Internet led to the information age. One key component in developing these new technologies is to assemble individual atomic and molecular building blocks into larger structures with fundamentally new properties and functions. Nature is very efficient at assembling multi scale building blocks such as proteins, lipids, and minerals into nanostructured materials such as bone, teeth, diatoms, eggshells, seashells, cell membranes, and DNA. Surfactant and colloidal building block can also be assembled into different nanoscale materials and devices by utilizing hydrophobic/hydrophilic and other surface interactions. Using these concepts, this dissertation focuses on the syntheses and applications of nanostructured particles assembled from multi scale building blocks. Important factors in the synthesis of the particles include particle size, particle morphology, pore size and pore structure. Five different types of nanostructured particles assembled from different multi scale building blocks are demonstrated in this work: (1) Spherical metal/silica mesoporous particles with high surface areas and controllable pore sizes, pore structures, and metal content are synthesized from surfactant, silicate, and metal building blocks for catalytic applications; (2) Mesoporous hollow spheres with controllable pore sizes and pore structures are synthesized from surfactant, silica, and polystyrene building blocks; (3) Spherical mesoporous carbon particles with controllable pore sizes and pore structures are templated from silica particles assembled from silica and surfactant building blocks; (4) Spherical mesoporous, microporous, and bimodal carbon particles are synthesized from sucrose and silica building blocks and tested for hydrogen storage applications; and (5) Sub-micrometer sized mesoporous silica particles are prepared from the high energy ball milling of mesoporous silica xerogels assembled from silica and surfactant building blocks. These examples demonstrate the feasibility, efficiency, and flexibility of assembling nanostructured particles tailored for specific applications from different multi scale building blocks
acase@tulane.edu

The 4-hydroxycyclopentenones are a family of compounds found in nature, not only with medicinal properties, but can also be used as pesticides. Although with no knowledge of it, traditional medicine used of herbs and plants with healing properties for numerous diseases, which later came to be assign to this family of compounds. Due to its many applications, the synthesis of 4-hydroxycyclopentenones is an area of great interest in chemical research. In this work was applied the method developed by Piancatelli, in furan rings derivatives, with the aim of creating a library of new biologically active 4-hydroxycyclopentenones derivatives. This method has been used for the synthesis of simple cyclopentenones. Excellent yields were obtained by various research groups, having been one of the reasons for the choice of this method. The other was its simplicity, as it’s an acid catalysis reaction with a Lewis acid or even, in a greener version, with microwave catalysis in water.

abstract: The production of monomer compounds for synthesizing plastics has to date been largely restricted to the petroleum-based chemical industry and sugar-based microbial fermentation, limiting its sustainability and economic feasibility. Cyanobacteria have, however, become attractive microbial factories to produce renewable fuels and chemicals directly from sunlight and CO2. To explore the feasibility of photosynthetic production of (S)- and (R)-3-hydroxybutyrate (3HB), building-block monomers for synthesizing the biodegradable plastics polyhydroxyalkanoates and precursors to fine chemicals, synthetic metabolic pathways have been constructed, characterized and optimized in the cyanobacterium Synechocystis sp. PCC 6803 (hereafter Synechocystis 6803). Both types of 3HB molecules were produced and readily secreted from Synechocystis cells without over-expression of transporters. Additional inactivation of the competing PHB biosynthesis pathway further promoted the 3HB production. Analysis of the intracellular acetyl-CoA and anion concentrations in the culture media indicated that the phosphate consumption during the photoautotrophic growth and the concomitant elevated acetyl-CoA pool acted as a key driving force for 3HB biosynthesis in Synechocystis. Fine-tuning of the gene expression levels via strategies, including tuning gene copy numbers, promoter engineering and ribosome binding site optimization, proved critical to mitigating metabolic bottlenecks and thus improving the 3HB production. One of the engineered Synechocystis strains, namely R168, was able to produce (R)-3HB to a cumulative titer of ~1600 mg/L, with a peak daily productivity of ~200 mg/L, using light and CO2 as the sole energy and carbon sources, respectively. Additionally, in order to establish a high-efficiency transformation protocol in cyanobacterium Synechocystis 6803, methyltransferase-encoding genes were cloned and expressed to pre-methylate the exogenous DNA before Synechocystis transformation. Eventually, the transformation efficiency was increased by two orders of magnitude in Synechocystis. This research has demonstrated the use of cyanobacteria as cell factories to produce 3HB directly from light and CO2, and developed new synthetic biology tools for cyanobacteria.
Dissertation/Thesis
Ph.D. Biological Design 2014

The purpose of this research activity has been the development of new and efficient systems for the capture of CO2 from a gas stream in a sustainable way from an energetic, economic and environmental point of view. The chemical absorption by aqueous alkanolamines is considered the most efficient and mature technique for the CO2 capture and separation. Alkanolamines are widely used due to the fast reaction with CO2 and to their solubility in water. In particular aqueous 2-amine ethanol (MEA) has a long story as efficient systems for CO2 separation in ammonia and hydrogen plants, natural gas extraction and gas refinery. Recently, these aqueous sorbents have been also studied for application on CO2 removing from industrial exhaust streams. However, the high operating costs associated to the thermal regeneration of the sorbents because of the particularly high evaporation enthalpy and heat capacity of water, are the major obstacles to extensive application to large scale commercial plants. In addition, the higher is the desorption temperature, the greater are the amine decomposition and evaporation, as well as equipment corrosion, thus increasing the maintenance costs of the CCS process. With the aim of taking advantages of the high efficiency of conventional aqueous alkanolamines yet reducing their disadvantages, we have been pursuing a lab-scale research on alternative absorbent formulations aimed at reducing the energy of the absorbent regeneration and the amine degradation, yet maximising the CO2 capture. With the objective of reducing the energy required by the desorption process, in this thesis has been devised the strategy to avoid water. The replacement of water by organic solvents, or the absence of any solvents, may redirect the reaction of amines with CO2 towards less stable species which, consequently, require lower stripping temperatures at room pressure. The study has been focused on amines which combine high reaction rate with CO2 in a non-aqueous environment, with lower reaction enthalpy (in absolute value) and therefore these absorbents require lower regeneration temperatures compared to those of the aqueous solutions (75-95 °C at room pressure instead of 120-140 °C under pressure). Furthermore, the lower operating temperatures reduce the decomposition rate and the loss of the amines. As additional, not negligible benefit, the absence of water strongly reduces the equipment corrosion and avoids foaming problems. A first stage of this study has been devoted to solutions of alkanolamines in organic solvents. Replacing water with organic solvents may provide significant advantages in regard to the reduced absorbent decomposition and to the energy saving in the regeneration step due to the lower heat capacity (about half), the lower heat of vaporization of organic solvents and the higher boiling temperature compared to water. Furthermore, the use of organic solvents does not require major changes to the equipment which works with aqueous solutions. The sorbents formulated comprised some single or blended alkanolamines and alcohol mixtures containing ethylene glycol. 13C NMR analysis indicates that CO2 is reversibly captured in solution as either monoalkyl carbonate (R-OCO2−) and amine carbamate. Due to the lower stability of monoalkyl carbonates with respect to HCO3− and to the carbamates which are formed in the aqueous solutions, stripping temperatures of 75–90°C at room pressure are sufficient to attain absorption efficiencies greater than 90%. Between different formulation designed, one of the best performing was tested on the pilot plant of the ENEL coal-fired power plant located in Brindisi. Even if the replacement of water by organic solvents may reduce the costs of the stripping process, a lot of energy is wasted by the organic solvent heating from the absorption to the desorption temperatures. Moreover, the solvent, either water or alcohols account for about 70% of the absorbent and therefore requires very large equipments. The avoidance of any solvent, should be a decisive improvement towards the ideal absorbent. Therefore, the study has been focused on amines capable of absorbing CO2 without any dilution provided they are liquid before and after the carbon dioxide uptake. A technique of reversible CO2 capture that does not require absorbent dilution would have beneficial effects over those based on diluted absorbents, in that it avoids the sensible heat and vaporization heat of the solvent that contribute to the overall reboiler duty, as long as the operational conditions and the efficiency of the two techniques were comparable. Further potential benefits would be the reduced mass of the absorbent (water accounts for 70 wt % of the mass of aqueous MEA) and, consequently, an appreciable reduction of the plant size. In this study has been formulated two different classes of solvent-free single-component absorbents based on inexpensive and commercially available amine, in particular some secondary amines and some secondary alkanolamines. CO2 is captured with high efficiency (over 90%) as amine carbamate and amine-carbamic acid. In another part of the study has been devised and developed the use of biphasic sorbents. In such technique, the absorbent solution, after the reaction with CO2, separates into two phases (liquid/liquid or liquid/solid) that comprise the solvent and, separately, the carbonatated species. In this way it is possible to desorb the sole carbonatated phase, preventing the energy wasted by solvent heating. After its thermal regeneration, the absorbent is mixed again with the solvent to get back the starting absorbent solution. This biphasic technique combines the advantages of both organic solvents and solvent–free sorbents previously studied. A first series of experiments, which involves sodium and potassium carbonates and some amines (piperazine and AMP), has been completed with good results. Another series of tests very promising, using alkanolamines in low viscous solvents, is still under development. In these three years, in our laboratory, has been also developed a new concept of CO2 capture technology which combines the CO2 abatement with the production of commercially valuable products. Turning carbon dioxide into useful chemicals in relatively mild conditions circumvent most of the drawbacks of the energy consuming steps of CO2 desorption, absorbent regeneration as well as of CO2 transporting and ultimate disposal. It has been verified the efficient absorption of CO2 by water-ethanol ammonia and by some non-aqueous amines. These experiments were addressed to recover the captured CO2 as solid ammonium carbamate or carbamates of the protonated amines. By heating the solid ammonium carbonate and bicarbonate mixtures or the amine carbamates in a closed reactor, we obtained their conversion into urea and, respectively, 1,3-disubstituted ureas with reasonable yields (30-50%). Urea is the world's most used fertilizer and it is produced in large quantities, while 1,3-disubstituted ureas are valuable products with a wide range of application as intermediates in agrochemical, pharmaceutical, dye chemicals and raw materials of polyurethanes. In addition, it has been studied the chemistry of the CO2 uptake by resorcinol (1,3-dihydroxy benzene) in alkaline aqueous and water/glycerol solutions under different experimental conditions, with the purpose of unveiling the reaction mechanism and maximizing the resorcinol conversion into β-resorcylic acid (2,4-dihydroxybenzoic acid).