UNIVERSITY OF PANNONIA

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1 UIVESITY F PAIA FMATI F 2,3-DIHYD-2,2,2-TIPHEYLPHEATH[9,10-d]- 1,3,2λ 5 -XAZAPHSPHLES AD THEI EACTIS WITH CAB DIXIDE AD DIXYGE Theses of the doctoral (Ph.D) dissertation by: István Bors M.Ed in Chemistry and Environmental studies Supervisor: Dr. Gábor Speier Professor Emeritus, D.Sc Doctoral School in Chemistry and Environmental Sciences Institute of Chemistry Department of rganic Chemistry Veszprém 2015

2 ABSTACT This work presents the formation of 2,3-dihydro-2,2,2-triphenylphenanthro[9,10-d]-1,3,2λ 5 -oxazaphosphole and its 2,7-derivative via [4+1] cycloaddition of triphenylphosphane and the corresponding phenanthrenequinone monoimine. This compound can react at ambient conditions with perhaps the two most important small-molecules, dioxygen and carbon-dioxide. The work of the thesis investigates the formation of the above mentioned compound and its reactions with 2 and C 2. The product of the cheletropic reaction was found as catalyst for the biomimetic oxidation triphenylphosphane to its oxide and the reaction mechanism seems to be very similar to the flavoprotein monooxygenases. Various structural methods (I, UV-vis, X-ray crystallography, M, GC-MS, CV) were used to characterize the products and the intermediates. Detailed kinetic investigation of the reactions have been performed and the three mentioned mechanisms were proposed.

3 Theses of the dissertation 1. I have ascertained, by synthetic method, that 2-amino and 2-dimethylaminophenanthrenequinone do not react even at reflux temperature with atmospheric pressure H 3 by addition-elimination reaction. The experiments were supported by cyclic voltammetry. 2. The existence of radical intermediates by the formation of 2,3-dihydro-2,2,2- triphenyl-phenanthro[9,10-d]-1,3,2λ 5 -oxazaphospholes was confirmed using ES and UV-vis spectroscopy. The unique role of the hydrogen of the imine was approved by indirect experiments. A mathematical model was developed from proposed mechanism and was used to determine the numerical values of the kinetic parameters. (TFigure 1.) k 2 50 o C CH 3 C, 3h = - H K 2 k 3 * H k 3 H H H = H K 1 H + = t-bu, H, Br, 2 TFigure 1. The proposed mechanism of reaction between 2,3-dihydro-2,2,2-triphenylphenanthro[9,10-d]-1,3,2λ 5 -oxazaphospholes and triphenylphosphine (K = exp(55566/t)±3.6; k 2 = exp(-1268/t)± / mm -1 h -1 ; k 3 = exp(-33585/t)± / h -1 )

4 3. I have ascertained, when 2,3-dihydro-2,2,2-triphenyl-phenanthro[9,10-d]-1,3,2λ 5 - oxazaphosphole react with dioxygen, a reactive intermediate is formed, which is able to oxygenate. Based on ES spectroscopy experiments, reversible equilibrium was upheld between the reactive intermediate and oxazaphospholyl radical. The existence of intermediates was supposed by liquid phase infrared spectroscopy and iodometry. The appearance of intermediates was verified by indirect experimental methods (Triethylamine catalysis, reaction between potassium superoxide and 2,3-dihydro-2,2,2-triphenyl-phenanthro[9,10-d]- 1,3,2λ 5 -oxazaphosphole and between triphenylphosphine and 9,10- phenanthrenequinone monoxime). 4. The kinetic parameters were described in the oxygenation reaction of by using catalytic amounts of 2,3-dihydro-2,2,2-triphenyl-phenanthro[9,10-d]-1,3,2λ 5 - oxazaphosphole. (TFigure 2.) H -H H -PPh PPh 3 3 H + - H TFigure 2. Proposed biomimetic mechanism for the triphenylphosphine oxygenation (k 3 = 0.391±0.008 M -2 s -1 ) 5. The catalytic oxygenation of with dioxygen in the presence of 2,3-dihydro-2,2,2-triphenyl-phenanthro[9,10-d]-1,3,2λ 5 -oxazaphosphole bears flavoprotein monooxygenase functional enzyme mimic.

5 6. Analysing the product of the isotope labeled experiment with I and MS between 2,3-dihydro-2,2,2-triphenyl-phenanthro[9,10-d]-1,3,2λ 5 -oxazaphosphole and carbon dioxide at ambient conditions, carbon dioxide was verified as oxygen source. Detailed kinetic investigation of the reaction have been performed and based on the experimental data the mechanism was proposed. (TFigure 3.) - + C - -H + H + H H = H, t-bu TFigure 3. Proposed reaction mechanism between carbon dioxide and 2,3-dihydro-2,2,2-triphenylphenanthro[9,10-d]-1,3,2λ 5 -oxazaphosphole (k 2 = M -1 s -1 ) 7. A new synthetic route to a known compound (phenantro[9,10-d][1,3]oxazol- 2(3H)-one) was described with an environmentally friendly method. An unknown derivate of this compound (2,7-di-tert-butyl-phenantro[9,10- d][1,3]oxazol-2(3h)-one) was also described via the developed route.

6 List of related publications and lectures Publications: 1. I. Bors, J. Kaizer, G. Speier, Michel Giorgi, Carbon dioxide as a primary oxidant and a C1 building block. SC. Adv. 2014, 11, (86), I. Bors, J. Kaizer, G. Speier, Kinetics and mechanism of oxygenation with 3 2 catalyzed by a 1,3,2-oxazaphosphole as flavin mimic. SC. Adv. 2014, 4, (33), Lectures: 1. G. Székely, I. Bors,. Bagi, J. Kaizer, G. Speier, xygenation and oxidation of and phenols by 3 2 catalyzed by a 1,3,2-oxazaphosphole as organic cofactor mimic. WG4/WG1 Meeting CST Action CM1201 Biomimetic adical Chemistry, Tenerife, 1-3 ctober, 2014, pp I. Bors,. Bagi, J. Kaizer, G. Speier, adical Chemistry in the Activation of 3 2. CST CM 1201 Meeting, Paris, ovember, 2013, pp I. Bors, G. Speier, J. Kaizer, xidation by -P- ing Containing rganocatalysts: Formation and Kinetic Studies. XXIV. International Conference on Coordination and Bioinorganic Chemistry, Smolenice, 2-7 June, 2013, pp I. Bors, G. Speier, J. Kaizer, J. S. Pap, rganocatalytic xygenation with Triplet Dioxygen. CA Meeting, Marseilles, March, 2012, pp. 22. Poster: 1. I. Bors,. Bagi, G. Speier, J. Kaizer, Mimicking the ole of Flavin by an Artificial rganocatalyst. 6 th European Young Investigator Conference, Słubice, June, 2013, pp. 51.

7 Hungarian lectures: 1. Bors I., Kaizer J., Speier G., Kis molekulák aktiválása 1,3,2-oxazafoszfolok-kal. XIX. emzetközi Vegyészkonferencia, agybánya, ovember 2013, pp Bors I., Kaizer J., Speier G., rganokatalitikus oxidáció új heterociklusos katalizátorral. Kialakulás és kinetikai vizsgálatok. XVIII. emzetközi Vegyészkonferencia, Félixfürdő, ovember 2012, pp. 34. AWAD 3. Bors I., Kaizer J., Pap J. S., Speier G., A fémes enzimkofaktortól a szerves kofaktorig. XLVI. Komplexkémiai Kollokvium, Mátraháza, May 2012, pp. 7.

8 List of unrelated publications and lectures Publications: 1. Bors I., Kaizer J., Pap J. S., Speier G., Measuring the Antioxidative Capacity of Some Selenium Compound with Standard Methods. Hung. J. Chem., 2012, 118, J. S. Pap, B. Kripli, I. Bors, D. Bogáth, M. Giorgi, J. Kaizer, G. Speier, Transition metal complexes bearing flexible 3 or 3 donor ligands: eactivity toward superoxide radical anion and hydrogen peroxide J. Inorg. Biochem., 2012, 117, 60. Lectures: 1. Speier G., Bagi., Bors I., Kaizer J., Tiofenol katalitikus oxidációja dioxigénnel. XVIII. emzetközi Vegyészkonferencia, Félixfürdő, ovember 2012, pp Kaizer J., Pap J. S., Kripli B., Bors I., Bogáth D., Speier G., Cu-,Mn-,Fe-,Co- és i- tartalmú SD és kataláz enzimmodellek előállítása és vizsgálata. XLVI. Komplexkémiai Kollokvium, Mátraháza, May 2012, pp Bors I., Kaizer J., Pap J. S., Speier G., éhány fitokemikália és szelénvegyület antioxidációs hatásának vizsgálata. XLV. Komplexkémiai Kollokvium, Mátraháza, May 2010, pp. 22. Posters: 1. Zs. Pintér, I. Bors, P. Slama, M. eglier, G. Speier, ew Dicopper Complexes as Catalysts in Catechol xidation. CST Action WG2 Meeting, Göttingen, April, Bors I., Speier G.: éhány szelénorganikus vegyület antioxidatív hatásának vizsgálata standardizált módszerekkel. MKE 1. emzeti Konferencia, Sopron, May 2011.