Search results for "Suzuki"
showing 10 items of 80 documents
Application of molecular topology for the prediction of the reaction times and yields under solvent-free conditions
2010
Ball milling and conventional magnetic stirring can be used to support different laboratory techniques with a highly efficient mixing of reagents under solvent-free conditions. By using multilinear regression and linear discriminant analysis, topological-mathematical models have been built to predict the yield and the reaction time for organocatalytic reactions, Suzuki reactions and reactions of synthesis of heterocyclic compounds. The results from the in silico predictions confirm the usefulness of the approach followed.
Single-Walled Carbon Nanotube–Polyamidoamine Dendrimer Hybrids for Heterogeneous Catalysis
2016
We report the synthesis and catalytic properties of single-walled carbon nanotube-polyamidoamine dendrimers hybrids (SWCNT-PAMAM), prepared via a convergent strategy. The direct reaction of cystamine-based PAMAM dendrimers (generations 2.5 and 3.0) with pristine SWCNTs in refluxing toluene, followed by immobilization and reduction of [PdCl4](2-), led to the formation of highly dispersed small palladium nanoparticles homogeneously confined throughout the nanotube length. One of these functional materials proved to be an efficient catalyst in Suzuki and Heck reactions, able to promote the above processes down to 0.002 mol % showing a turnover number (TON) of 48 000 and a turnover frequency (T…
Energy Transfer at the Single-Molecule Level: Synthesis of a Donor-Acceptor Dyad from Perylene and Terrylene Diimides
2013
In 2004, we reported single-pair fluorescence resonance energy transfer (spFRET), based on a perylene diimide (PDI) and terrylene diimide (TDI) dyad (1) that was bridged by a rigid substituted para-terphenyl spacer. Since then, several further single-molecule-level investigations on this specific compound have been performed. Herein, we focus on the synthesis of this dyad and the different approaches that can be employed. An optimized reaction pathway was chosen, considering the solubilities, reactivities, and accessibilities of the building blocks for each individual reaction whilst still using established synthetic techniques, including imidization, Suzuki coupling, and cyclization reacti…
Efficient synthesis of racemic and chiral alkenyl sulfoxides by palladium-catalyzed Suzuki coupling
2010
Alkenyl sulfoxide derivatives are obtained in high yields through a palladium-catalyzed Suzuki/Miyaura cross-coupling reaction of racemic and chiral 1-halo sulfoxides with aryl and alkenyl boronic acids. Chiral substrates react with no loss of optical purity and high optical yields. The reaction takes place with different palladium catalysts, such as Pd(PPh 3 ) 4 or Pd(OAc) 2 /DABCO. Although nitrogen ligands like DABCO lead to an active palladium catalyst, they are less effective than the phosphine ones.
Palladium nanoparticles immobilized on halloysite nanotubes covered by a multilayer network for catalytic applications
2018
The synthesis of pure fine chemicals for industrial purposes is one of the most attractive challenges of chemical research. The use of catalytic pathways mediated by palladium nanoparticles (PdNPs) for C-C bond formation is a useful way to obtain these kinds of compounds. To achieve this objective, the PdNPs can be efficiently loaded on a functionalized natural nanostructured support such as halloysite nanotubes (HNTs). Hybrid materials based on thiol functionalized halloysite nanotubes and highly cross-linked imidazolium salts were successfully developed and used for the stabilization of PdNPs. The HNT/Pd hybrids were thoroughly characterized from a physico-chemical point of view and teste…
Common fixed points for self mappings on compact metric spaces
2013
In this paper we obtain a result of existence of points of coincidence and of common fixed points for two self mappings on compact metric spaces satisfying a contractive condition of Suzuki type. We also present some examples to illustrate our results. Moreover, using the scalarization method of Du, we deduce a result of common fixed point in compact cone metric spaces.
6-Amino-5-tiofēn-piridiletiķskābes sintēzes metodes izstrāde.
2021
6-Amino-5-tiofēn-piridiletiķskābes sintēzes metodes izstrāde. Ostrovska L., zinātniskais vadītājs Dr. chem. Mārtiņš Katkevičs. Bakalaura darbs, 34 lappuses, 16 attēli, 2 tabulas, 66 literatūras avoti. Latviešu valodā. Bakalaura darbā tika izvērtētas 6-amino-5-tiofēn-piridiletiķskābes sintēzes iespējas. Literatūras apskats satur informāciju par 2-(6-aminopiridīn-3-il)acetātu un 2-amino-3- halogēnpiridīnu iegūšanas metodēm, kā arī par 2-tiofēnanilīnu sintēzi Suzuki-Mijauras reakcijā. Eksperimentālajā daļā aprakstīta mērķa savienojuma sintēze
3H-1,2-Benzoksatiepīna-2,2-dioksīda arilatvasinājumu sintēze
2019
3H-1,2-Benzoksatiepīna-2,2-dioksīda arilatvasinājumu sintēze. Balašova A., zinātniskie vadītāji MSc. ķīm. Pustenko A. un Dr. ķīm., doc. Kļimenkovs I. Bakalaura darbs, 43 lappuses, 19 attēli, 9 tabulas, 27 literatūras avoti. Latviešu valodā. Darbā tika sintezēti 3H-1,2-benzoksatiepīna-2,2-dioksīda arilatvasinājumi. Sintezēto 3H-1,2-benzoksatiepīna-2,2-dioksīda atvasinājumu struktūra tika apstiprināta ar KMR un IS spektroskopijas metodēm. Literatūras apskatā apkopota informācija par olefīnu metatēzes un Suzuki-Mijauras šķērssametināšanas reakcijām.
3H-Benzoksafosfepīna-2-oksīda atvasinājumu sintēze
2021
3H-Benzoksafosfepīna-2-oksīda atvasinājumu sintēze. Balašova A., zinātniskais vadītājs Dr. chem. Žalubovskis R. Maģistra darbs, 76 lappuses, 23 attēli, 8 tabulas, 58 literatūras avoti. Latviešu valodā. Darbā tika sintezēti 3H-benzoksafosfepīna-2-oksīda atvasinājumi. Kā galvenā stadija mērķsavienojumu sintēzē izmantota cikla saslēgšanas metatēzes reakcija. Sintezēto 3H-benzoksafosfepīna-2-oksīda atvasinājumu struktūra tika apstiprināta ar KMR, IS un AIMS analīzes metodēm. Dažiem atvasinājumiem tika noteiktas ogļskābes anhidrāžu inhibēšanas aktivitātes. Literatūras apskatā apkopota informācija par cikla saslēgšanas metatēzi, Suzuki–Mijauras un McKenna reakciju.
LIQUIDI IONICI E FULLERENI: PIATTAFORME PER NUOVI MATERIALI
The synthesis of innovative catalysts based on different carbon nanoforms (CNFs), namely fullerene C60 and carbon nanotubes (CNTs), and their application in Suzuki and Heck C-C coupling reactions, constitutes the common thread of the first part (Chapter 1 and 2) of this thesis. C60 and CNTs were functionalized with ionic liquids (ILs) and poly-amidoamine (PAMAM) dendrimers, respectively, and used as supports for palladium nanoparticles (PdNPs). Moreover, additional supported catalytic systems based on one of the synthesized C60-IL hybrids were prepared and successfully employed in the title coupling reactions. The final part (Chapter 3) of the thesis deals on the microwave-mediated synthesi…