3,5-DIMETIL-1-TIOKARBOXAMIDPIRAZOL BINUKLE�RIS R�Z- �S KOBALT-HALOGENID KOMPLEXEINEK TERMIKUS BOML�SA
Szerz�: Magyari J�zsef, III. �vfolyam
T�mavezet�k: Dr. Leovac Vukadin �s Dr. M�sz�ros Sz�cs�nyi Katalin egyetemi tan�rok
Int�zm�ny: �jvid�ki Egyetem, Term�szettudom�nyi Kar, K�miai Int�zet
Vajdas�gi Magyar Fels�oktat�si Koll�gium

A pirazol ligandumok komplexei ir�nti nagy �rdekl�d�s miatt �vek �ta foly� tudom�nyos kutat�saink c�lja, hogy vizsg�ljuk azokat a legjelent�sebb t�nyez�ket, amelyek a pirazolsz�rmaz�kok �s az �tmeneti f�mionok k�z�tt lej�tsz�d� komplexk�pz�d�si reakci�k folyamat�t meghat�rozz�k. Egyes pirazolsz�rmaz�kok valamint a bel�l�k k�pz�d� komplexek biol�giai aktivit�ssal rendelkeznek. Ez�rt nagy sz�ks�g van a k�s�rleti felt�telek ismeret�re, amelyek adott szerkezet� term�k el��ll�t�s�t teszik val�sz�n�v�. Gyakorlati felhaszn�l�sra alkalmas ve-gy�letek eset�ben a piaci forgalmaz�s elengedhetetlen felt�tele a term�k h��ll�s�g�nak meghat�roz�sa. A h�boml�s folyamat�nak ismerete adatokat szolg�ltat az egyes k�t�sek k�t�ser�ss�g�r�l, valamint �tmutat�sk�nt szolg�lhat �j vegy�letek szil�rd f�zis� el��ll�t�s�hoz.
E dolgozatunkban a Cu2L2Cl4, Cu2L2Br2 �s Co2L2Cl4 komplexek (L = 3,5-dimetil-1-tiokarboxamidpirazol) valamint egy �jonnan el��ll�tott Cu2L2Cl2 �sszet�tel� vegy�let termikus boml�sfolyamatait t�rgyaljuk. Az els� h�rom vegy�let el��ll�t�si adatai �s krist�ly-szerkezete m�r ismert (I. Radosavljevi� Evans, J. A. K. Howard, L. E. M. Howard, J. S. O. Evans, �. K. Ja�imovi�, V. S. Jevtovi�, V. M. Leovac, Inorg. Chim. Acta, � nyomd�ban). Az �j vegy�let szint�zis�n�l azt vizsg�ltuk, hogyan hat ki a f�mion �s a ligandum m�lar�nya a k�pz�d� term�k szerkezet�re. Ugyanis a r�z(II)-klorid �s L 1 : 1 m�lar�ny� metanolos oldat�b�l k�t term�k k�pz�dik. El�sz�r a z�ld sz�n� Cu2L2Cl4 r�z(II) komplex krist�lyai v�lnak le, majd a sz�rletb�l a termodinamikailag stabilisabb narancs sz�n� Cu2L2Cl2 r�z(I) komplex csap�dik le. Szint�n metanolos oldatban, de a r�z(II)-klorid �s L 1 : 2 m�lar�ny� reakci� elegy�b�l viszont csak ez ut�bbi term�k k�pz�dik. E vegy�let �sszet�tel�t �s val�sz�n� szerkezet�t az elemanal�zis adatai alapj�n, FT-IR spektrometri�s adatokb�l valamint m�gneses �s vezet�k�pess�gi m�r�sek eredm�nyeib�l hat�roztuk meg. E komplex termikus boml�sa sor�n keletkez�, 480 �s 530 K h�m�rs�kleti tartom�nyban stabilis k�ztiterm�k szerkezet�t szint�n vizsg�ltuk.

Kulcsszavak: 3,5-dimetil-1-karboxamidpirazol komplexek, r�z(I)-, r�z(II)- �s kobalt(II) klorid ill. bromid komplexek, termikus anal�zis

THERMAL DECOMPOSITION OF BINUCLEAR COPPER AND COBALT COMPLEXES WITH 3,5-DIMETHYL-1-CARBOXAMIDEPYRAZOLE
Author: Magyari J�zsef, III year student
Mentors: Dr. Vukadin Leovac and Dr. Katalin M�sz�ros Sz�cs�nyi, profs.
Organization: University of Novi Sad, Faculty of Sciences, Department for Chemistry
Hungarian College for Higher Education in Vojvodina

Because of the great interest in complexes with pyrazole based ligands, the aim of our systematic studies is to investigate the most important factors that govern the course of the complex formation reaction of pyrazole derivatives with transition metal ions. Some of the pyrazole derivatives as well as their complexes possess biological activity. Hence it is very important to know about the experimental conditions which with a high probability provide a compound of a given structure. In the case of compounds with a commercial application, for the distribution of the products it is compulsory to determine their thermal stability. The knowledge of thermal decomposition pathway gives data on bond strength of specific bonds, besides it refers to the possibility of a solid phase synthesis of new compounds.
In this paper we describe the thermal decomposition of Cu2L2Cl4, Cu2L2Br2 and Co2L2Cl4 complexes (L = 3,5-dimethyl-1-carboxamidepyrazole) whose synthesis and crystal structure had been published (I. Radosavljevi� Evans, J. A. K. Howard, L. E. M. Howard, J. S. O. Evans, �. K. Ja�imovi�, V. S. Jevtovi�, V. M. Leovac, Inorg. Chim. Acta, In Press) and a newly synthesized Cu2L2Cl2 compound. In this case, we examined the influence of the central ion to the ligand mole ratio on the structure of the complex. Namely, in reaction of copper(II) chloride and L in a mole ratio of 1 : 1, from the methanolic solution two compounds are forming. At the beginning, yellow-green crystals of copper(II) complex, Cu2L2Cl4, are separating. Then, from the filtrate, the thermodynamically more stable orange Cu2L2Cl2 copper(I) complex is deposited. Also from the reaction mixture in methanol, but with a copper(II) chloride to L mole ratio of 1:2 only the latter compound is obtained. The composition and the probable structure of this product has been determined on the basis of elemental analysis data, FT-IR spectrometry, magnetic and conductivity measurement data. We also examined the structure of the intermediate which is for-ming during its thermal decomposition and is stable in a temperature range from 480 to 530 K.

Keywords: 3,5-dimethyl-1-carboxamidpyrazole complexes, copper(I)-, copper(II)- and cobalt(II) chloride or bromide complexes, thermal analysis.

TERMI�KA DEKOMPOZICIJA BINUKLEARNIH KOMPLEKSA HALOGENIDA BAKRA I KOBALTA SA 3,5-DIMETIL-1-TIOKARBOKSAMIDPIRAZOLOM
Autor: Magyari J�zsef, student III godine
Mentori: Dr. Vukadin Leovac i Dr. Katalin M�sz�ros Sz�cs�nyi, red. profesori
Ustanova: Univerzitet u Novom Sad, Prirodno-matemati�ki fakultet, Departman za hemiju
Kolegijum za visoko obrazovanje vojvo�anskih Ma�ara

S obzirom na veliki interes za komplekse sa pirazolnim ligandima, cilj na�ih vi�egodi�njih istra�ivanja je ispitivanje najzna�ajnijih faktora koji odredjuju tok reakcije kompleksiranja derivata pirazola sa jonima prelaznih metala. Neki derivati pirazola kao i njihovi kompleksi poseduju biolo�ku aktivnost. Stoga je vrlo zna�ajno poznavanje eksperimentalnih uslova koji sa velikom verovatno�om vode do nastajanja proizvoda odre�ene strukture. U slu�aju jedinjenja sa prakti�nom primenom, za njihovo plasiranje na tr�i�tu neophodno je odrediti termi�ku stabilnost proizvoda. Poznavanje toka termi�ke dekompozicije daje podatke o ja�ini pojedinih veza, a pored toga ukazuje na mogu�nost sinteze novih jedinjenja u �vrstoj fazi.
U ovom radu opisujemo termi�ku dekompoziciju kompleksa Cu2L2Cl4, Cu2L2Br2 i Co2L2Cl4 (L = 3,5-dimetil-1-tiokarboxamidpirazol) �ije su sinteze i kristalne strukture ranije objavljene (I. Radosavljevi� Evans, J. A. K. Howard, L. E. M. Howard, J. S. O. Evans, �. K. Ja�imovi�, V. S. Jevtovi�, V. M. Leovac, Inorg. Chim. Acta, u �tampi) i novosintetisanog jedinjenja Cu2L2Cl2. Pri tome smo ispitivali uticaj molskog odnosa jona metala i liganda na strukturu nastalog kompleksa. Naime, pri odnosu bakar(II) hlorida i L 1 : 1 iz metanolnog rastvora nastaju dva produkta. Prvo se izdvajaju zeleni kristali kompleksa bakra(II), Cu2L2Cl4. Iz filtrata se talo�i termodinami�ki stabilniji kompleks oran� boje bakra(I), Cu2L2Cl2. Iz reakcione sme�e tako�e metanolnog rastvora bakar(II)-hlorida i L ali u odnosu 1 : 2 nastaje samo ovaj poslednji proizvod. Sastav i verovatnu strukturu ovog jedinjenja smo odredili na osnovu podataka elementalne analize, FT-IR spektrometrije i magnetnim odnosno konduktometrijskim merenjima. Tako�e smo ispitivali strukturu intermedijera koji nastaje tokom termi�ke dekompozicije ovog jedinjenja, i koji je stabilan u temperaturskoj oblasti od 480 do 530 K.

Klju�ne re�i: 3,5-dimetil-1-karboksamidpirazol kompleksi, bakar(I)-, bakar(II)- i kobalt(II) hloridni odnosno bromidni kompleksi, termi�ka analiza.