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V okviru magistrske naloge sem sintetiziral nove spojine z biciklo[2.2.2]oktenskim skeletom. Z Diels–Alderjevo reakcijo 2H-piran-2-onov z maleinanhidridom sem pripravil dva biciklo[2.2.2]oktena s pripojenima sukcinanhidridnima fragmentoma, ki sem ju uporabil pri nadaljnjih reakcijah derivatizacije. Z reakcijo nukleofilne substitucije s hidrazinom na dianhidridnih obročih in nadaljnjo reakcijo N-substituirane aminske spojine z aromatskimi ali heteroaromatskimi aldehidi sem sintetiziral serijo osemnajstih biciklo[2.2.2]oktenov s pripojenimi hidrazonskimi fragmenti. Za razliko od sintez z aldehidi je reakcija s ketonom potekla slabše, saj je željeni produkt kljub daljšem reakcijskem času nastal le v sledovih. Pripravil sem tudi biciklo[2.2.2]oktene s pripojenimi acilhidrazidnimi fragmenti, vendar produktov ni bilo mogoče izolirati v čisti obliki. Za sintezo teh spojin sem izhodne acilhidrazide pripravil iz analognih etilnih estrov z reakcijo s hidrazin hidratom. Karakterizacijo produktov s pripojenimi acilhidrazidi je ovirala otežena rotacija vezi v DMSO, zaradi katere so bili signali na 1H NMR in 13C NMR spektrih razširjeni. Omenjeno težavo sem poskušal rešiti z merjenjem spektrov pri višji temperaturi ali z uporabo devteriranega topila z manjšo gostoto. Reakcije sinteze obeh tipov produktov so potekale s segrevanjem reakcijske zmesi v zaprtih debelostenskih ACE cevkah, kot topilo pa sem uporabil n-BuOH. V obeh primerih so 1H NMR spektri pokazali nastanek asimetričnih stranskih produktov, ki sem jih potrdil z MS analizo. Za metodo čiščenja produktov sem uporabil prekristalizacijo iz EtOH ali MeOH, kar je bilo v večini primerov uspešno. Sinteze tiosemikarbazidnih derivatov biciklo[2.2.2]oktenov niso bile uspešne. Pri pogojih refluksa so produkti nastali v sledovih, pri pogojih segrevanja reakcijske zmesi v zaprtih debelostenskih ACE cevkah pa je prišlo do razpada in nastanka biciklo[2.2.2]oktenov s pripojenimi N-aminosukcinimidnimi obroči. Prav tako je bila neuspešna sinteza biciklo[2.2.2]oktena z N-acetaldehidnima fragmentoma. The main emphasis of this master degree thesis is synthesis of novel compounds with bicyclo[2.2.2]octene framework. Two starting bicyclo[2.2.2]oct-7-enes with two fused succinanhydride moieties, which were used in all further derivatization reactions, were synthesized with Diels–Alder reaction of 2H-pyran-2-ones with maleic anhydride. Synthesis of a series of eighteen novel bicyclo[2.2.2]octenes with fused hydrazone moiety was achieved with nucleophilic substitution of hydrazine on cyclic anhydride fragments and subsequent reaction of N-substituted amine group with various aromatic and heteroaromatic aldehydes. In contrast to reactions of aldehydes reactions of ketones were less successful, after long reaction times only traces of desired products were observed. Bicyclo[2.2.2]octenes with fused acylhydrazide fragments were also prepared, although I was unable to isolate them in pure form. For synthesis of these compounds I prepared starting acylhydrazides from corresponding ethyl esters in reaction with hydrazine hydrate. Characterisation of acylhydrazide derivatives of bicyclo[2.2.2]octenes with 1H NMR and 13C NMR analysis was complicated by restricted rotation of acylhydrazide moieties in DMSO-d6 solution, which caused broadening of signals in the spectrum. I tried to solve this problem with measuring NMR spectra at higher temperature or in deuterated solvents with lower density. The syntheses of all aforementioned final compounds were carried out with heating the reaction mixture in closed heavy wall pressure ACE tubes. The n-BuOH was used as the solvent. In all cases the 1H NMR analysis showed the presence of asymetric by- products, which were further confirmed with MS analysis. In most cases these were removed from crude products with recrystalisation in EtOH or MeOH. The preparation of thiosemicarbazide derivatives of bicicylo[2.2.2]octenes was not successful. After refluxing reaction mixture only traces of desired products were found. When same reactions were carried out in closed heavy wall pressure ACE tubes degradation of compounds present in the reaction mixture occured, leading to the formation of bicyclo[2.2.2]octene with fused succinimide fragments. Synthesis of bicyclo[2.2.2]octene with two fused N-acetaldehyde moieties was also unsuccessful with no traces of desired products observed.

Različno substituirani 3-benzoilamino-2H-piran-2-oni z Diels–Alderjevo cikloadicijo z maleinahidridom ali N-fenilmaleimidom vodijo v nastanek biciklo[2.2.2]oktenskih sistemov. V svojem magistrskem delu opisujem izvedbo omenjenih reakcij v topilih, ki jih je možno pridobivati iz biomase. Takšna topila predstavljajo eno izmed novejših vrst topil, ki se uvrščajo pod zeleno kemijo. Uspešno sem sintetizirala več različno substituiranih biciklo[2.2.2]oktenskih produktov v para-cimenu, α-pinenu in evkaliptolu. V para-cimenu sem tudi preizkusila in optimizirala nekatere reakcije, da bi dosegale čim višje konverzije, bile čim manj energijsko potratne in tako čim bolje ustrezale principom zelene kemije. Omenjene Diels–Alderjeve reakcije sem preizkusila tudi v limonenu, kjer reakcija ni potekla, in γ-valerolaktonu, kjer so bile težave z izolacijo produkta. Produkte, ki so uspešno nastali, sem okarakterizirala s pomočjo IR, 1H NMR in MS analize. Various substituted 3-benzoylamino-2H-pyran-2-ones lead to bicyclo[2.2.2]octene derivatives upon reaction with maleic anhydride or N-phenylmaleimide via Diels–Alder cycloaddition. In this master's thesis, such reactions are described in biomass-derived solvents. This type of solvent is one of the newer types of green solvents. Various substituted bicyclo[2.2.2]octenes were synthesized in para-cymene, α-pinene and eucalyptol. Some of the reactions carried out in para-cymene were optimized to achieve high conversion rates, to be as energy efficient as possible, and to satisfy as many principles of green chemistry as possible. The aforementioned synthesis of bicyclo[2.2.2]octenes was also attempted in limonene, where the reaction did not occur and in γ-valerolactone, where problems with the isolation of the product were encountered. The successfully synthesized products were characterized by IR, 1H NMR and MS analytical methods.

V magistrskem delu sem raziskoval Diels–Alderjevo reakcijo med substituiranimi 2H-piran-2-oni in maleinanhidridom. Izhodne 2H-piran-2-one sem pripravil z enoločno sintezo, pri čemer so nastali različno substituirani 3-benzoilamino-2H-piran-2-oni. Slednji pri reakcijah z maleinanhidridom pod termičnimi pogoji običajno tvorijo enega izmed dveh možnih produktov: biciklični dvojni adukt (derivatiziran biciklo[2.2.2]okten) ali termodinamsko stabilnejši aromatski produkt (derivat izobenzofurana). Z optimizacijo reakcijskih pogojev sem poskušal pripraviti ter izolirati obe vrsti produktov. Izkazalo se je, da je reaktivnost 2H-piran-2-onov, ki vsebujejo elektron donorske substituente, pri reakciji z maleinanhidridom večja kot je reaktivnost 2H-piran-2-onov z elektron privlačnimi substituenti v obeh primerih nastanejo biciklični dvojni adukti z dobrimi izkoristki, v drugem primeru pa tudi aromatizirani izobenzofuranski produkti. 2H-piran-2-oni z elektron donorskimi substituenti torej preferenčno tvorijo biciklične adukte, ki se v večini primerov tudi po daljšem reakcijskem času in višji reakcijski temperaturi slabo pretvarjajo v aromatske. In the present work I investigated the Diels–Alder reaction between substituted 2H-pyran-2-ones and maleic anhydride. The starting 2H-pyran-2-ones were synthesised by “one pot” synthesis, resulting in various substituted 3-benzoylamino-2H-pyran-2-ones. The latter when reacted with maleic anhydride under thermal conditions usually form one of the two possible products: a bicyclic double adduct (derivatized bicyclo[2.2.2] octene) or a thermodynamically more stable aromatic product (isobenzofuran derivative). By optimizing the reaction conditions, I tried to prepare and isolate both types of products. The reactivity of 2H-pyran-2-ones with electron donor substituents in the reaction with maleic anhydride has been shown to be greater than the reactivity of 2H-pyran-2-ones with electron-withdrawing substituents, resulting in the formation of bicyclic double adducts (with good yields) in the former case and aromatic isobenzofuran products in the latter. In contrast, 2H-pyran-2-ones with electron donor substituents preferentially form a bicyclic adduct, which in most cases is poorly converted to aromatic even after a long reaction time and higher reaction temperature.

V magistrskem delu sem raziskovala Diels–Alderjevo reakcijo 3-benzoilamino-6-(2-tienil)-2H-piran-2-ona z maleinanhidridom pod različnimi reakcijskimi pogoji. Pri reakciji pod refluksom je nastal biciklični dvojni adukt (substituiran biciklo[2.2.2]okt-7-en). Reakcija pod mikrovalovnim obsevanjem je vodila do nastanka istega bicikličnega dvojnega adukta ter neznanega stranskega produkta, za katerega sem kasneje ugotovila, da gre za aromatski produkt (derivat izobenzofurana) in našla ustrezne mikrovalovne pogoje za sintezo le-tega kot edinega produkta. Optimizirala sem tudi reakcijske pogoje za sintezo aromatskega produkta pod klasičnimi pogoji z dodatkom aktivnega oglja. Mikrovalovna sinteza aromatskega produkta je bila bistveno hitrejša, okolju prijaznejša, produkt je bil čistejši in izkoristek višji v primerjavi s klasično sintezo. Tekom eksperimentalnega dela sem opazila razpadanje bicikličnega dvojnega adukta na TLC silikagelnih ploščicah ter razpad nekoliko podrobneje raziskala. Silikagel bi potencialno lahko bil uporaben kot katalizator za hidrolizo anhidridnih obročev bicikličnih dvojnih aduktov. In present work I investigated the Diels–Alder reaction of 3-benzoylamino-6-(2-thienyl)-2H-pyran-2-one with maleic anhydride under different reaction conditions. Reaction under reflux conditions yielded bicyclic double adduct (substituted bicyclo[2.2.2]oct-7-ene). Microwave irradiation led to formation of the same bicyclic double adduct and an unknown by-product, which I later identified as aromatic product (isobenzofuran derivative) and found appropriate microwave conditions for its formation as the only product. I also optimized reaction conditions for synthesis of aromatic product under conventional conditions with addition of activated charcoal. Microwave synthesis of aromatic product was much faster, environmentally friendly, product was cleaner and yield was higher compared to conventional synthesis. During research I also noticed and further investigated degradation process of bicyclic double adducts on TLC silicagel plates. Silicagel could be potentially used as catalyst for hydrolysis of anhydride moiety in bicyclic double adducts.