Sharif Digital Repository

In this research, four N2O2–azacrown macrocyclic ligands with naphthalene pendant arms (L1-L4) were synthesized using direct synthesis. The products were characterized applying 1H and 13C {1H} NMR spectroscopy, IR and Mass spectrometry. Interaction of these ligands with [60]fullerene and Cu(II) were monitored respectively by fluorescent as well as UV-vis spectroscopy and applying Benesi-Hildebrand equation. These intercations were compared with N2O2 macrocyclic ligands in previous experiments in terms of their calculated association constants (Ka). According to our results, the presence of naphthalene pendant arm groups led to increase the interaction with [60]fullerene compared to the... 

The reaction of O2N2-donor naphthodiazacrown, with salicylaldehyde afforded new O3N2-donor macrocyclic ligands (L1-3naph) mounted with 1,3-diazcyclohexane subring in high yield. The product was characterized by IR, 1HNMR spectroscopy as well as elemental microanalysis and single crystal X-ray studies (just for L3naph). The interactions of [60]fullerene in presence and absence of base, Cu(II), Hg(II) and Zn(II) with L1-3naph were investigated employing fluorescence spectroscopy. The efficient fluorescence quenching of L1-3naph in presence of C60, Cu(II)( L1-2naph) and the fluorescence enhancement in presence of Hg(II) and Zn(II) indicated that the interaction with [60]fullerene Hg(II) and... 

In the study of molecules and chemical structures, especially fullerenes, they can be modeled to graphs. In this way, we can consider some chemical properties as graphical properties such as, perfect matching, connectivity, Hamiltonian; in order to obtain some results about some families of chemical structures.In this thesis, at first we mention some graphical and combinatorial properties. Then,we survey some results about fullerenes, and finally we investigate some properties of specific families of fullerenes. Furthermore, we mention some existing open problems in each case  

New N4O6 molecular tweezers were synthesized from N2O2 benzo- and naphthodiazacrown macrocycles bearing benzylic dialdehydes as a flexible and semi-flexible spacer in a short time and at room temperature. The products were characterized by IR, 1H and 13C NMR spectroscopy as well as elemental microanalysis. The interactions of some of these tweezers with C60, Cu(II), Co(II), Ni(II), Zn(II), Hg(II) and Mn(II) were investigated by employing UV-Vis and fluorescence spectroscopy. Efficient fluorescence responses for 2NM3BD were observed in the presence of C60, Cu(II), Mn(II), Hg(II) and Zn(II). Meanwhile, the calculation of the association constants (K¬BH) employing Benesi-Hildebrand equation in... 

In the field of high-pressure material science, diverse carbon systems under pressure have been intensively studied with interest in synthesizing new phases. A variety of these synthetic phases which have met various applications in today technology are called the amorphous diamond. The pressure-induced structural transition of carbonaceous material to amorphous diamond is realized by shock compression and rapid quenching. The shock compression and rapid quenching generate the high pressure (several GPa) and the temperature (several hundred K) in a fraction of a microsecond.Since the mechanical and electrical properties of the synthetic diamond are severely sensitive to the atomic structure,... 

In the present research, a series of bimacrocyclic tweezer anchored through azobenzene moiety were synthesized and characterized by applying IR spectroscopy, 1H and 13C{1H} NMR, fluorescence spectroscopy, UV-visible spectroscopy, mass spectrometry and elemental analysis and in some cases by X-ray crystallography. Firstly, UV-visible spectroscopy established that the irradiation of the tweezers with UV light promoted the trans to cis isomerization. On the other hand, thermal cis-trans isomerization behavior of the azobenzene moiety in tweezers was surveyed in which the cis isomers were formed of the heating at 50 oC for 5 minutes. Where the -OH group was replaced with 4-toluenesulfonyl... 

Nanomachines are molecules inspired by natural molecular machines and are able to move and transport at the nanoscale. Due to the advancement of nanotechnology, the need to move materials and energy on a small scale is necessary more than ever. Nanocars are artificial molecular machines with chassis, axles, and wheels designed for nanoscale transport at materials’ surfaces. Understanding the dependence of surface dynamics of nanocars on the substrate’s physico-chemical properties is critical to the design of the transport properties of such man-made nanoscale devices. Among the multitude of potential substrates for the nanotransporters, graphene exhibits intrinsic ripples on its surface,... 

In this project, in continuation of a PhD resreach undertaken in this research group in 2017, the synthesis and study of two new tweezer and linker molecule bearing azobenzene moiety were carried out, characterized by applying IR spectroscopy, ¹H and ¹³C {¹H} NMR, fluorescence spectroscopy, UV-visible spectroscopy, elemental analysis and X-ray crystallography. Firstly, interaction of T2 with meso-tetraphenylporphyrinato zinc(II) and aluminium tetraphenylporphyrinato were studied using the fluorescence spectroscopy. The formation constant of T2 in cis and trans isomer with ZnTPP was measured as 5.1(±0.4) ×108 and 2.0×108(±1074) dm6mol-2, respectively. The formation constant of T2 in with... 

A set of azacrown macrocyclic ligands bearing pyridine moiety (bp, 1p, 2p) were synthesized and characterized by single-crystal X-ray diffraction (SCXRD), elemental analysis, FT-IR, 1H and 13C NMR methods. The complexes of zinc tetraphenylporphyrin (ZnTPP) with the bp and 1p as the axial ligand were synthesized and characterized by single-crystal X-ray diffraction, elemental analysis, IR, 1H and 13C NMR, fluorescence, UV-vis, cyclic voltammetry, together with TD DFT calculations. By employing this method for ZnTPPbenz and ZnTPPH complexes elucidated that the pyridine moiety was bonded through the fifth- coordination site on the zinc metal atom. In the following study, the coordination...