NMR studija reakcije H/D izmjene kod 1,1-dimetil propragilnog alkohola. Učinak organskog otapala

master's thesis

• Title (english): NMR study of the H/D exchange reaction in 1,1-dimethylpropargyl alcohol. The effect of the organic solvent
• Author: Mateo Celinić
• Mentor: Valerije Vrček (mentor)
• Committee member: Valerije Vrček (predsjednik povjerenstva)
• Committee member: Viktor Pilepić (član povjerenstva)
• Committee member: Davor Šakić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Pharmacy and Biochemistry; (Department of organic chemistry); Zagreb
• Defense date and country: 2024-08-29, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry; Organic Chemistry

Abstract

Potaknut potrebom za jednostavnom i ekonomičnom pripravom, sintetski korisnih, deuteriranih terminalnih alkina, u ovom se radu nastavlja istraživanje o izotopnoj H/D izmjeni na terminalnom alkinu 1,1-dimetil-propargilnog alkohola (ROH). Ranije je prikazano uspješno deuteriranje upotrebom teške vode (D2O) kao jedinog reaktanta uz ROH, a ovaj rad proširuje istraživanje tog procesa dodatkom organskih otapala u reakcijsku smjesu. U ovome su slučaju to deuterirani aceton i deuterirani acetonitril. Razlog njihovom dodatka je taj što Budući da nisu svi spojevi s terminalnom alkinskom skupinom topljivi u vodi, dodatak organskog otapala može povećati njihovu topljivost u smjesi vode i organskog otapala. Stoga je važno ispitati kako se mijenja brzina H/D izmjene dodatkom organskog otapala, te dolazi li do inhibicije reakcije.
Za istraživanje je korištena 1H NMR spektroskopija. Snimanjem spektara kroz određeno vrijeme uočava se postepeni pad signala alkinske skupine jer se 1H proton supstituira izotopom 2H čiji signal nije vidljiv u 1H NMR spektru. Obradom rezultata dolazi se do spoznaje da dodatak dvaju organskih otapala smanjuje brzinu reakcije te da je ovisnost poluvremena reakcije o masenom udjelu otapala eksponencijalna. Pri relativnom malim masenim udjelima org.otapala ( do 20%) smanjenje brzine nije značajano, dok se pri višim masenim udjelima lako uočava ovisnost brzine H/D izmjene o dielektričnoj konstanti organskog otapala.. Ovaj diplomski rad može poslužiti za nastavak istraživanja utjecaja niza drugih otapala na ishod reakcije.

Abstract (english)

Driven by the need for simple and economical preparation of synthetically useful deuterated terminal alkynes, this work continues the investigation into the isotopic H/D exchange on the terminal alkyne of 1,1-dimethyl-propargyl alcohol (ROH). Previously, successful deuteration using heavy water (D2O) as the sole reactant with ROH was demonstrated. This study extends that research by adding organic solvents to the reaction mixture. In this case, deuterated acetone and deuterated acetonitrile were used. The reason for their addition is that not all compounds with terminal alkyne groups are soluble in water, and the addition of an organic solvent can increase their solubility in a water-organic solvent mixture. Therefore, it is important to examine how the rate of H/D exchange changes with the addition of organic solvents and whether the reaction is inhibited.
1H NMR spectroscopy was used for the investigation. By recording spectra over time, a gradual decrease in the signal of the alkyne group is observed as the 1H proton is substituted by the 2H isotope, whose signal is not visible in the 1H NMR spectrum. Analysis of the results reveals that the addition of the two organic solvents reduces the reaction rate and that the dependence of the reaction's half-life on the solvent's mass fraction is exponential. At relatively low mass fractions of the organic solvent (up to 20%), the reduction in rate is not significant, while at higher mass fractions, the dependence of the H/D exchange rate on the dielectric constant of the organic solvent is easily noticeable. This thesis can serve as a basis for further research into the influence of various other solvents on the reaction outcome.

• Keywords: deuteriranje; H/D izmjena; NMR; 1; 1-dimetil-propargilni alkohol; deuterijev oksid; D2O; deuterirani aceton; ACE-d6; deutreiranih acetonitril; ACN-d3
• Keywords (english): deuteration; H/D exchange; NMR; 1; 1-dimethyl-propargyl alcohol; deuterium oxide; D2O; deuterized acetone; ACE-d6; deuterized acetonitrile; ACN-d3
• Language: croatian
• URN:NBN: urn:nbn:hr:163:827941
• Study programme: Title: Pharmacy - integrated undergraduate and graduate - university study; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: sveučilišni magistar farmacije (sveučilišni magistar farmacije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-10-11 12:59:59