Cikloadicija furfurilgvanidina i derivata acetilendikarboksilne kiseline. Eksperimentalni i računski studij

master's thesis

• Title (english): Cycloaddition of furfurylguanidines and derivatives of acetylenedicarboxylic acid. Experimental and computational study
• Author: Ian Horvat
• Mentor: Irena Škorić (mentor)
• Mentor: Zoran Glasovac (komentor)
• Committee member: Irena Škorić (predsjednik povjerenstva)
• Committee member: Domagoj Vrsaljko (član povjerenstva)
• Committee member: Zoran Glasovac (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2024-09-30, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

U ovom radu sintetizirani su policiklički derivati gvanidina ukorporirani u oksanorbornenski kostur u obliku heksafluorfosfatnih soli. Ključni korak u pripravi svakog od spojeva jest
Diels-Alder reakcija 2-(furfurilamino)imidazolidinijevog heksafluorfosfata s različitim esterima acetilendikarboksilne kiseline u mikrovalnom reaktoru, dok je konačan produkt dobiven intramolekulskom aza-Michaelovom adicijom gvanidina na nastali supstituirani oksanorbornadien. Diels-Alderova reakcija je odabrana kao ekološki prihvatljiv pristup pripravi ciljnih molekula, dok je aza-Michaelova reakcija provedena propuštanjem sirovog produkta preko stupca SiO2. Tijekom istraživanja je utvrđeno kako smanjenje omjera reaktanata zahtijeva dulje vrijeme reakcije ili višu temperaturu što dovodi do bitnog povećanja udjela polimera u smjesi. Izolirani spojevi su okarakterizirani spektroskopskim tehnikama te je za svaki od pročišćenih produkata ispitana kokatalitička aktivnost u aldolnoj reakciji cikloheksanona i 4-klorbenzaldehida. Računskim putem je istražen utjecaj supstituenata na barijeru cikloadicije i mogući utjecaj supstituenta na cikloadiciju. Utvrđeno je kako većina supstituenata podižu barijeru cikloadicije u odnosu na metilni derivat što je u skladu s primijećenim nižim prinosima. DFT računima je okarakteriziran i utjecaj vodikove veze na promjene energija graničnih orbitala i na asinkronost reakcije.

Abstract (english)

In this paper, polycyclic derivatives of guanidine incorporated into an oxanorbornene skeleton in the form of hexafluorophosphate salts were synthesized. The key step in the preparation of each of the compounds is the Diels-Alder reaction of
2-(furfurylamino)imidazolidine hexafluorophosphate with various esters of acetylenedicarboxylic acid in a microwave reactor, while the final product is obtained by intramolecular aza-Michael addition of guanidine to the resulting substituted oxanorbornadiene. The Diels-Alder reaction was chosen as an environmentally friendly approach to the preparation of target molecules, while the aza-Michael reaction was performed by passing the crude product through a SiO2 column. During the research, it was found that reducing the ratio of reactants requires a longer reaction time or a higher temperature, which leads to a significant increase in the proportion of polymers in the mixture. The isolated compounds were characterized by spectroscopic techniques, and the co-catalytic activity in the aldol reaction of cyclohexanone and 4-chlorobenzaldehyde was tested for each of the purified products. The influence of substituents on the cycloaddition barrier and the possible influence of substituents on cycloaddition were investigated computationally. Most of the substituents were found to raise the cycloaddition barrier compared to the methyl derivative, which is consistent with the observed lower yields.
The influence of the hydrogen bond on the changes in the energies of the frontier orbitals and on the asynchrony of the reaction was also characterized by DFT calculations.

• Keywords: acetilendikarboksilna kiselina; cikloadicija; gvanidin; kokataliza; oksanorbornen
• Keywords (english): acetylenedicarboxylic acid; cycloaddition; guanidine; cocatalysis; oxanorbornene
• Language: croatian
• URN:NBN: urn:nbn:hr:149:024877
• Study programme: Title: Applied Chemistry - Graduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry; Course: Applied organic chemistry; Study programme type: university; Study level: graduate; Academic / professional title: sveučilišni/a magistar/magistra primijenjene kemije (sveučilišni/a magistar/magistra primijenjene kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-11-11 11:33:57